tag:theconversation.com,2011:/id/topics/calcium-3116/articlesCalcium – The Conversation2024-03-07T13:32:32Ztag:theconversation.com,2011:article/2180212024-03-07T13:32:32Z2024-03-07T13:32:32ZLead from old paint and pipes is still a harmful and deadly hazard in millions of US homes<figure><img src="https://images.theconversation.com/files/572091/original/file-20240130-19-tg1jv8.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C3763%2C2822&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">When lead-based paint blisters and cracks, lead dust may be released in the air. </span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/lead-based-paint-abatement-royalty-free-image/1735464372?phrase=lead%2Bpoisoning%2B">Douglas Rissing/iStock via Getty Images Plus</a></span></figcaption></figure><p>Lead is a potent neurotoxin that causes severe health effects such as <a href="https://doi.org/10.1186/s12889-023-15874-7">neurological damage, organ failure and death</a>. </p>
<p>Widely used in products such as paint and gasoline until the late 1970s, lead continues to contaminate environments and harm the health of people around the world. </p>
<p>The World Health Organization estimates that more than <a href="https://www.who.int/news-room/fact-sheets/detail/lead-poisoning-and-health#">1 million deaths each year are attributable to lead poisoning</a>, with the highest exposures in developing nations. Lead continues leaching from old paint, pipes and industrial sources into soils, homes and waterways across the globe. </p>
<p>In more recent years, this number has risen at an incredible pace, with some research showing that nearly 5.5 million adults <a href="https://doi.org/10.1016/S2542-5196(23)00166-3">die from lead-related health complications</a>.</p>
<p>I am a <a href="https://hhs.purdue.edu/directory/aaron-specht/">health physicist</a> and my research focuses on ways to improve the technology <a href="https://doi.org/10.1021/acs.est.0c06622">used to screen for lead</a> and other <a href="https://doi.org/10.1021/acs.est.1c00937">environmental toxicants</a>. In developing and applying my technologies to see how people are affected by toxicants like lead, I have tested more than 20,000 people around the world over the past five years.</p>
<p>This preventable health crisis especially threatens children during periods of <a href="https://doi.org/10.1289/ehp.7688">critical brain development</a> but can also <a href="https://doi.org/10.1093/aje/kwh333">impair intellectual development</a> and <a href="https://doi.org/10.1016/S2468-2667(18)30025-2">long-term health</a> in adults. Understanding and addressing this persistent problem will require improved monitoring, targeted remediation and a great deal more awareness and dialogue.</p>
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<iframe width="440" height="260" src="https://www.youtube.com/embed/aqWvRh8rfLU?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Lead is especially toxic to children under age 6.</span></figcaption>
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<h2>How lead damages the body</h2>
<p>Lead enters the body through three routes: <a href="https://www.atsdr.cdc.gov/csem/leadtoxicity/exposure_routes.html">ingestion, absorption or inhalation</a>. Once inside, <a href="https://doi.org/10.3390/ijerph182212051">lead mimics calcium</a> by binding to proteins and enzymes where calcium is typically involved. </p>
<p>Lead looks a lot like calcium to many of the systems in our body. By hijacking these calcium-dependent processes, lead disrupts many normal functions ranging from neurological function to cardiovascular health. </p>
<p>When lead replaces calcium in these processes, it causes <a href="https://www.who.int/news-room/fact-sheets/detail/lead-poisoning-and-health#">irreversible damage</a>, even at low levels of chronic exposure. Studies show that low levels of lead are associated with dangerous <a href="https://doi.org/10.1016%2Fj.envres.2016.10.007">lifelong illnesses such as Alzheimer’s</a> and <a href="https://doi.org/10.1289%2Fehp.9785">heart disease</a>.</p>
<p>Furthermore, like calcium, lead accumulates <a href="https://doi.org/10.1289/ehp.919133">in our teeth and bones</a>. This compounds lead’s adverse effects as our bodies grow and age, since the lead in bone will reappear as our body looks to its calcium stores during periods of growth or, critically, during pregnancy. </p>
<p>Lead exposure can come from many sources in our daily life, from water systems using <a href="https://www.epa.gov/ground-water-and-drinking-water/lead-service-lines">lead water lines</a> and <a href="https://www.hud.gov/program_offices/healthy_homes/healthyhomes/lead">legacy exposures from old paint</a> to things that people often don’t think about, such as <a href="https://doi.org/10.1016/j.envres.2023.115719">lead in firearms</a> or <a href="https://doi.org/10.1016/j.envres.2020.109860">metal pots and pans</a>. </p>
<p>Researchers often see <a href="https://doi.org/10.1001/jamapediatrics.2018.2382">exposures from soils</a> in highly polluted areas, but sometimes it can be <a href="https://doi.org/10.1016/j.jenvman.2022.115904">present in old donated toys</a> at a child’s day care. </p>
<p>Late in 2023, investigators working with the Centers for Disease Control and Prevention found <a href="https://www.cdc.gov/nceh/lead/news/lead-poisoning-outbreak-linked-to-cinnamon-applesauce-pouches.html">dangerous levels of lead in applesauce</a>, likely stemming from a cinnamon spice grinder. This highlights the <a href="https://www.nytimes.com/2024/02/27/world/europe/lead-applesauce-food-safety.html">Food and Drug Administration’s failures</a> in keeping lead out of the U.S. food supply. </p>
<h2>Fragmented testing</h2>
<p>Blood lead screening <a href="https://www.cdc.gov/nceh/lead/data/national.htm">serves as the first line of defense</a> against lead exposure, particularly in high-risk individuals and primarily in children. However, <a href="https://toxicfreefuture.org/research/children-at-risk/state-lead-screening-policies/">testing protocols and recommendations vary widely</a>, and most states lack universal testing mandates. </p>
<p>Even in cases where universal screening programs exist, the data obtained can be insufficient. This is because blood tests capture only recent exposure, and universal testing oftentimes mandates only one test of children within a six-year window. </p>
<p>This fragmented system, combined with research indicating that many doctors <a href="https://doi.org/10.1136/oemed-2023-109210">deviate from lead testing guidelines</a>, allows exposures to go undetected until irreversible neurological damage has been done. </p>
<p>We are hopeful that as research like ours draws more attention to the gravity of this issue, universal, standardized screening will become the norm across the U.S. This would save many children – and generations to come – from ongoing and preventable exposures.</p>
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<iframe width="440" height="260" src="https://www.youtube.com/embed/CXD_hh8zRiY?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Lead toxicity doesn’t affect just children.</span></figcaption>
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<h2>How testing is done</h2>
<p>Monitoring lead levels typically involves a <a href="https://www.cdc.gov/nceh/lead/prevention/blood-lead-levels.htm">simple blood test</a>, generally ordered by your doctor. These tests are widely available but <a href="https://doi.org/10.1016/j.chemosphere.2021.129832">can easily be inaccurate</a> based on when the test was taken. Since <a href="https://doi.org/10.1038%2Fs41370-018-0036-y">blood lead levels can change quickly</a>, children who get tested several weeks after exposure could falsely test as normal. </p>
<p>Moreover, because there is no requirement for doctors to be trained in how to test for and treat lead exposure, many pediatricians <a href="https://doi.org/10.1136/oemed-2023-109210">lack awareness about lead screening protocols</a>. As a result, many at-risk people <a href="https://doi.org/10.1289/EHP10335">are not being tested</a>. </p>
<p>When tests are given, they may yield inaccurate results due to the <a href="https://doi.org/10.1038%2Fs41370-018-0036-y">rapid changes in blood lead</a>. Or sometimes results are not properly reported to local health departments. Further complicating this, in 2010, the Centers for Disease Control and Prevention declared that the country’s progress in removing lead from gasoline was a <a href="https://www.cdc.gov/mmwr/preview/mmwrhtml/mm6019a5.htm">great public health achievment</a>. As a result, many lead-testing programs in the U.S. were discontinued, leading to critical information gaps. </p>
<p>However, there is some reason for optimism. Some state-based lead surveillance programs that were phased out in the early 2000s have been returning in recent years. A good example is my home state of Indiana. A law that <a href="https://www.in.gov/health/lead-and-healthy-homes-division/information-for-health-care-providers/testing-requirements/">went into effect on Jan. 1, 2023</a>, requires all health care providers serving children to offer lead testing to their patients. </p>
<p>Efforts from statewide programs like these will lead to more opportunities to inform physicians and to screen vulnerable populations.</p>
<h2>Ways to get tested</h2>
<p>Blood is by far the most widely used indicator for lead exposure. However, <a href="https://doi.org/10.1038/s41370-018-0036-y">in blood, lead dissipates quickly</a>, and after about a few weeks to a month, an exposure that was high enough to cause damage is no longer measurable from blood lead.</p>
<p>As part of my research, we have developed a handheld device that is able to <a href="https://doi.org/10.3109/1354750X.2016.1139183">noninvasively measure lead from bone</a> in minutes. Picture a Star Trek tricorder. We have patented the method we use to calculate lead in bone but currently have not commercialized it. </p>
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<a href="https://images.theconversation.com/files/579700/original/file-20240304-28-hr1ffe.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A hand wrapped around the handle of a small black, silver and gray lead-measuring device." src="https://images.theconversation.com/files/579700/original/file-20240304-28-hr1ffe.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/579700/original/file-20240304-28-hr1ffe.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=798&fit=crop&dpr=1 600w, https://images.theconversation.com/files/579700/original/file-20240304-28-hr1ffe.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=798&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/579700/original/file-20240304-28-hr1ffe.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=798&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/579700/original/file-20240304-28-hr1ffe.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1003&fit=crop&dpr=1 754w, https://images.theconversation.com/files/579700/original/file-20240304-28-hr1ffe.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1003&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/579700/original/file-20240304-28-hr1ffe.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1003&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The author holds the Star Trek-esque device that he and his team developed at Purdue University.</span>
<span class="attribution"><span class="source">Aaron James Specht</span>, <a class="license" href="http://creativecommons.org/licenses/by-nc-nd/4.0/">CC BY-NC-ND</a></span>
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<p>Bone lead is reflective of <a href="https://doi.org/10.1289/ehp.9783">years to decades of exposure</a> and is a more accurate test to reflect the permanence of damage induced by lead in the body. Bone lead has also been shown to have a strong relationship with <a href="https://doi.org/10.1515/reveh.2009.24.1.15">lead accumulation in the brain</a>, since lead hijacks places in both the bone and the brain where calcium is normally present. </p>
<p>Efficient and routine blood lead testing in children during their developmental stages could definitively identify exposure sources as they emerge. </p>
<p>While bone measurements allow researchers and physicians to effectively <a href="https://doi.org/10.1088/1361-6579/aa904f">measure years to decades of exposure</a>, health departments and the CDC currently lack the infrastructure to deploy this technology in communities that are highly affected by lead. </p>
<h2>What you can do</h2>
<p>People concerned about lead exposure <a href="https://www.cdc.gov/nceh/lead/prevention/testing-children-for-lead-poisoning.htm#">should request a blood lead test</a> from their doctor. Parents of young children should proactively ask pediatricians to conduct lead screening. If you live in an old home, especially one with peeling paint, you can contact your local health department to test for possible lead paint. </p>
<p>Additionally, your local water service provider should be able to tell you if lead water lines are in use leading to your home. Unfortunately, lead has no particular smell or taste to differentiate it from other possible contaminants.</p>
<p>Children and adults with elevated blood lead levels should talk to their pediatrician or doctor about effective <a href="https://www.cdc.gov/nceh/lead/advisory/acclpp/actions-blls.htm">follow-up testing</a> and potential dietary changes to promote lead excretion naturally. </p>
<p>For very high exposures, a treatment known as <a href="https://www.atsdr.cdc.gov/csem/leadtoxicity/patient_treatment.html#">chelation therapy</a>, which involves an oral medication that binds to lead so that it can be excreted in urine, has been shown to be <a href="https://doi.org/10.1203/00006450-200011000-00007">effective at reducing blood lead levels</a>. </p>
<p>These people should also notify their local health department, which can identify and remove lead sources in their environment to eliminate the risk to both current and future residents.</p><img src="https://counter.theconversation.com/content/218021/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Aaron Specht receives funding from the National Institutes of Health, Centers for Disease Control, and JPB Foundation. </span></em></p>Although the US banned lead-based paint in 1978, homes built before then commonly contain lead paint.Aaron Specht, Assistant Professor of Health Physics, Purdue UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2229912024-02-22T19:21:00Z2024-02-22T19:21:00ZWe looked at 700 plant-based foods to see how healthy they really are. Here’s what we found<figure><img src="https://images.theconversation.com/files/576089/original/file-20240215-24-n2yy4i.jpg?ixlib=rb-1.1.0&rect=0%2C1%2C998%2C664&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/womans-hand-holding-homemade-vegan-burger-1963150717">YesPhotographers/Shutterstock</a></span></figcaption></figure><p>If you’re thinking about buying plant-based foods, a trip to the supermarket can leave you bewildered.</p>
<p>There are plant-based burgers, sausages and mince. The fridges are loaded with non-dairy milk, cheese and yoghurt. Then there are the tins of beans and packets of tofu.</p>
<p>But how much is actually healthy?</p>
<p>Our nutritional audit of more than 700 plant-based foods for sale in Australian supermarkets has just been <a href="https://www.sciencedirect.com/science/article/pii/S0889157524000516">published</a>. We found some products are so high in salt or saturated fat, we’d struggle to call them “healthy”.</p>
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<p>
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Read more:
<a href="https://theconversation.com/the-vegans-are-coming-whats-fuelling-the-interest-in-plant-based-eating-123869">The vegans are coming! What's fuelling the interest in plant-based eating?</a>
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</p>
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<h2>We took (several) trips to the supermarket</h2>
<p>In 2022, we visited two of each of four major supermarket retailers across Melbourne to collect information on the available range of plant-based alternatives to meat and dairy products.</p>
<p>We took pictures of the products and their nutrition labels.</p>
<p>We then analysed the nutrition information on the packaging of more than 700 of these products. This included 236 meat substitutes, 169 legumes and pulses, 50 baked beans, 157 dairy milk substitutes, 52 cheese substitutes and 40 non-dairy yoghurts.</p>
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Read more:
<a href="https://theconversation.com/4-plant-based-foods-to-eat-every-week-and-why-science-suggests-theyre-good-for-you-157235">4 plant-based foods to eat every week (and why science suggests they're good for you)</a>
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<h2>Plant-based meats were surprisingly salty</h2>
<p>We found a wide range of plant-based meats for sale. So, it’s not surprising we found large variations in their nutrition content. </p>
<p>Sodium, found in added salt and which contributes to <a href="https://www.heartfoundation.org.au/bundles/healthy-living-and-eating/salt-and-heart-health">high blood pressure</a>, was our greatest concern.</p>
<p>The sodium content varied from 1 milligram per 100 grams in products such as tofu, to 2,000mg per 100g in items such as plant-based mince products.</p>
<p>This means we could eat our entire <a href="https://www.betterhealth.vic.gov.au/health/healthyliving/salt">daily recommended sodium intake</a> in just one bowl of plant-based mince. </p>
<p>An <a href="https://www.tandfonline.com/doi/full/10.1080/09637486.2022.2137786">audit</a> of 66 plant-based meat products in Australian supermarkets conducted in 2014 found sodium ranged from 316mg in legume-based products to 640mg in tofu products, per 100g. In a <a href="https://www.mdpi.com/2072-6643/11/11/2603">2019 audit</a> of 137 products, the range was up to 1,200mg per 100g.</p>
<p>In other words, the results of our audit seems to show a consistent trend of plant-based meats <a href="https://www.tandfonline.com/doi/full/10.1080/09637486.2022.2137786">getting saltier</a>.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/575850/original/file-20240215-20-m7vzdu.jpg?ixlib=rb-1.1.0&rect=0%2C5%2C998%2C733&q=45&auto=format&w=1000&fit=clip"><img alt="Plant-based meat on supermarket shelves" src="https://images.theconversation.com/files/575850/original/file-20240215-20-m7vzdu.jpg?ixlib=rb-1.1.0&rect=0%2C5%2C998%2C733&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/575850/original/file-20240215-20-m7vzdu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/575850/original/file-20240215-20-m7vzdu.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/575850/original/file-20240215-20-m7vzdu.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/575850/original/file-20240215-20-m7vzdu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/575850/original/file-20240215-20-m7vzdu.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/575850/original/file-20240215-20-m7vzdu.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Looking for plant-based meat? Check the label for the sodium content.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/beyond-meat-impossible-foods-burger-patties-1981692338">Michael Vi/Shutterstock</a></span>
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<p>
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Read more:
<a href="https://theconversation.com/remind-me-again-why-is-salt-bad-for-you-179768">Remind me again, why is salt bad for you?</a>
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<h2>What about plant-based milks?</h2>
<p>Some 70% of the plant-based milks we audited were fortified with calcium, a nutrient important for <a href="https://www.betterhealth.vic.gov.au/health/healthyliving/calcium">bone health</a>.</p>
<p>This is good news as a <a href="https://www.mdpi.com/2072-6643/12/5/1254">2019-2020 audit</a> of 115 plant-based milks from Melbourne and Sydney found only 43% of plant-based milks were fortified with calcium.</p>
<p>Of the fortified milks in our audit, almost three-quarters (73%) contained the <a href="https://www.eatforhealth.gov.au/food-essentials/five-food-groups/milk-yoghurt-cheese-andor-their-alternatives-mostly-reduced-fat">recommended amount of calcium</a> – at least 100mg per 100mL.</p>
<p>We also looked at the saturated fat content of plant-based milks. </p>
<p>Coconut-based milks had on average up to six times higher saturated fat content than almond, oat or soy milks. </p>
<p><a href="https://www.mdpi.com/2072-6643/12/5/1254">Previous audits</a> also found coconut-based milks were much higher in saturated fat than all other categories of milks.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/575851/original/file-20240215-18-f937ou.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Supermarket shelves of plant-based milks" src="https://images.theconversation.com/files/575851/original/file-20240215-18-f937ou.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/575851/original/file-20240215-18-f937ou.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/575851/original/file-20240215-18-f937ou.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/575851/original/file-20240215-18-f937ou.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/575851/original/file-20240215-18-f937ou.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/575851/original/file-20240215-18-f937ou.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/575851/original/file-20240215-18-f937ou.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<span class="caption">Some plant-based milks were healthier than others.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/penang-malaysia-8-mar-2021-various-1932932891">TY Lim/Shutterstock</a></span>
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Read more:
<a href="https://theconversation.com/soy-oat-almond-rice-coconut-dairy-which-milk-is-best-for-our-health-146869">Soy, oat, almond, rice, coconut, dairy: which 'milk' is best for our health?</a>
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<h2>A first look at cheese and yoghurt alternatives</h2>
<p>Our audit is the first study to identify the range of cheese and yoghurt alternatives available in Australian supermarkets. </p>
<p>Calcium was only labelled on a third of plant-based yoghurts, and only 20% of supermarket options met the recommended 100mg of calcium per 100g. </p>
<p>For plant-based cheeses, most (92%) were not fortified with calcium. Their sodium content varied from 390mg to 1,400mg per 100g, and saturated fat ranged from 0g to 28g per 100g.</p>
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Read more:
<a href="https://theconversation.com/plain-greek-low-fat-how-to-choose-a-healthy-yoghurt-94295">Plain, Greek, low-fat? How to choose a healthy yoghurt</a>
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<h2>So, what should we consider when shopping?</h2>
<p>As a general principle, try to choose whole plant foods, such as unprocessed legumes, beans or tofu. These foods are packed with vitamins and minerals. They’re also high in dietary fibre, which is good for your gut health and keeps you fuller for longer.</p>
<p>If opting for a processed plant-based food, here are five tips for choosing a healthier option.</p>
<p><strong>1. Watch the sodium</strong></p>
<p>Plant-based meat alternatives can be high in sodium, so look for products that have <a href="https://www.eatforhealth.gov.au/eating-well/how-understand-food-labels/food-labels-what-look">around</a> 150-250mg sodium per 100g. </p>
<p><strong>2. Pick canned beans and legumes</strong></p>
<p>Canned chickpeas, lentils and beans can be healthy and low-cost <a href="https://www.heartfoundation.org.au/getmedia/71522940-decf-436a-ba44-cd890dc18036/Meat-Free-Recipe-Booklet.pdf">additions to many meals</a>. Where you can, choose canned varieties with no added salt, especially when buying baked beans.</p>
<p><strong>3. Add herbs and spices to your tofu</strong></p>
<p>Tofu can be a great alternative to meat. Check the label and pick the option with the highest calcium content. We found flavoured tofu was higher in salt and sugar content than minimally processed tofu. So it’s best to pick an unflavoured option and add your own flavours with spices and herbs.</p>
<p><strong>4. Check the calcium</strong></p>
<p>When choosing a non-dairy alternative to milk, such as those made from soy, oat, or rice, check it is fortified with calcium. A good alternative to traditional dairy will have at least 100mg of calcium per 100g. </p>
<p><strong>5. Watch for saturated fat</strong></p>
<p>If looking for a lower saturated fat option, almond, soy, rice and oat varieties of milk and yoghurt alternatives have much lower saturated fat content than coconut options. Pick those with less than 3g per 100g.</p><img src="https://counter.theconversation.com/content/222991/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Laura Marchese receives funding from a Deakin University Postgraduate Research Scholarship and a CSIRO R+ top-up scholarship. </span></em></p><p class="fine-print"><em><span>Katherine Livingstone receives funding from the National Health and Medical Research Council (APP117380) and the National Heart Foundation (ID106800). </span></em></p>You might be surprised how salty or fatty some plant-based foods are. Not so healthy now, are they?Laura Marchese, PhD Student at the Institute for Physical Activity and Nutrition, Deakin UniversityKatherine Livingstone, NHMRC Emerging Leadership Fellow and Senior Research Fellow at the Institute for Physical Activity and Nutrition, Deakin UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2232242024-02-21T13:04:38Z2024-02-21T13:04:38ZGut bacteria may explain why grey squirrels outcompete reds – new research<p>Across large parts of the UK, the native red squirrel has been replaced by the grey squirrel, a North American species. As well as endangering reds, grey squirrels pose a threat to our woodlands because of the damage they cause to trees. </p>
<p><a href="https://www.microbiologyresearch.org/content/journal/jmm/10.1099/jmm.0.001793">New research</a> from my colleagues and I compared the gut bacteria of red and grey squirrels. We found that differences between the two may explain their competition and red squirrel decline, as well as why grey squirrels are so destructive to woodland.</p>
<p>Grey squirrels were introduced to the UK between 1876 and 1929 and have displaced reds in most areas of the UK. Greys carry a virus called “squirrelpox”, which doesn’t affect them but leads to sickness and often death in red squirrels.</p>
<p>Grey squirrels are bigger than red squirrels and compete with them <a href="https://www.frontiersin.org/articles/10.3389/fevo.2023.1083008/full">for food and habitat</a>.
Acorns, a widespread food source, contain tannins, which are hard for red squirrels to digest. But greys can digest acorns easily, giving them an extra edge in competing for resources. </p>
<p>Grey squirrels frequently strip the bark from deciduous trees. In commercial plantations, the damage can lead to fungal infection and result in the tree producing low quality timber. The annual cost is an <a href="https://rfs.org.uk/insights-publications/rfs-reports/report-overview-the-cost-of-grey-squirrel-damage-to-woodland-in-england-and-wales/">estimated £37 million.</a> with sycamore, oak, birch and beech frequently targeted. </p>
<p>The grey squirrels select the strongest growing trees as these have bark containing the largest volume of sap. Intriguingly, grey squirrels do not select trees with the <a href="https://www.researchgate.net/publication/230344319_Bark-stripping_by_Grey_squirrels_Sciurus_carolinensis">highest sugar content</a>. This observation has led scientists to posit that the squirrels consume bark to obtain <a href="https://www.sciencedirect.com/science/article/pii/S0378112716300421?via%3Dihub">certain micro-nutrients</a>. </p>
<h2>Gut bacteria</h2>
<p>All mammals have microorganisms living in their intestines. For example, the typical human colon is host to at least <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5847071/">160 bacterial species</a>, while in birds, research has found thousands of different bacterial species in <a href="https://pubmed.ncbi.nlm.nih.gov/33868800/">chicken intestines.</a></p>
<p>The bacteria break down foods and help synthesise vitamins, complementing the enzymes secreted by the body. The diversity of these microorganisms, known as the “microbiota”, can reflect the level of health and also the diet of an individual. But we don’t know enough about the microbiota living in squirrel intestines. </p>
<p>The types of microbes present vary between species, yet the extent to which they differ between grey and red squirrels is unclear. We explored this and investigated the potential for any differences to affect competition between the two squirrel species. We also examined whether gut bacteria might be playing a role in bark stripping behaviour.</p>
<p>We sampled bacterial DNA from red and grey squirrel intestinal contents and performed gene sequencing to identify the range of bacteria present in the samples. The results were analysed to compare any important differences between the two.</p>
<figure class="align-center ">
<img alt="A cute red squirrels with a large bushy tail stands on the branch of a tree." src="https://images.theconversation.com/files/576545/original/file-20240219-20-ivfdqj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/576545/original/file-20240219-20-ivfdqj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=430&fit=crop&dpr=1 600w, https://images.theconversation.com/files/576545/original/file-20240219-20-ivfdqj.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=430&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/576545/original/file-20240219-20-ivfdqj.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=430&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/576545/original/file-20240219-20-ivfdqj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=541&fit=crop&dpr=1 754w, https://images.theconversation.com/files/576545/original/file-20240219-20-ivfdqj.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=541&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/576545/original/file-20240219-20-ivfdqj.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=541&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Ynys Môn off the north Wales coast is one of the few places in the UK where greys have been eradicated in favour of red squirrels.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/red-squirrel-views-around-north-wales-2232607907">Gail Johnson/Shutterstock</a></span>
</figcaption>
</figure>
<h2>Calcium</h2>
<p>Calcium is an important nutrient in the body and is required for healthy bones, muscles and nerves. It is especially needed by lactating animals and ones that are young and growing.</p>
<p>We found that grey squirrels may have the capacity to obtain the calcium that exists in tree bark thanks to the presence of a bacteria called “oxalobacter” in their gut. The calcium in tree bark comes in an insoluble form and is hard for an animal to digest. But oxalobacter would be able to change this into a form that could be more digestible. </p>
<p>Calcium levels <a href="https://www.sciencedirect.com/science/article/pii/S0378112716300421?via%3Dihub">increase in trees</a> as active growth resumes after winter dormancy. This happens immediately before the main squirrel bark-stripping season of May to July. Our research may therefore help to explain the destructive behaviour of grey squirrels and why red squirrels appear to strip bark much less frequently.</p>
<p>Our research also identified a significantly higher diversity of bacteria in the intestines of grey squirrels compared to red squirrels. This could hold the key to further understanding why grey squirrels outcompete red squirrels in the UK. </p>
<p>A more diverse range of bacteria being sustained in the gut means that grey squirrels potentially may be able to access a broader range of resources than red squirrels in addition to acorns.</p>
<h2>Adenovirus</h2>
<p>The grey squirrel harbours not just the squirrelpox virus, but also another potential threat – adenovirus. While this virus causes severe intestinal lesions in some red squirrels, curiously, grey squirrels never exhibit the same symptoms.</p>
<p>This discrepancy underscores the fascinating and complex potential role of gut microbiota. Research increasingly reveals their influence on everything from digestion to immune response, and even susceptibility to disease.</p>
<p>In the context of red squirrels, understanding how variations in their gut bacteria might predispose them to adenovirus becomes crucial. This is especially pertinent for captive breeding programs, where adenovirus infections pose a hurdle to successful reintroductions of red squirrels into the wild.</p>
<p>Given we only sampled red and grey squirrels from north Wales, we hope that future studies will map the gut microbiota of other European populations too. Such future research will continue to improve our knowledge of the competition between red and grey squirrels.</p><img src="https://counter.theconversation.com/content/223224/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Craig Shuttleworth does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>New research suggests the gut bacteria of red and grey squirrels differ significantly, potentially explaining the decline of the native red and the success of its grey counterpart.Craig Shuttleworth, Honorary Visiting Research Fellow, Bangor UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2127432023-09-22T13:15:43Z2023-09-22T13:15:43ZBones play an important role in our health – here’s how to keep them strong<figure><img src="https://images.theconversation.com/files/548525/original/file-20230915-17-zgaqyj.jpg?ixlib=rb-1.1.0&rect=0%2C13%2C4368%2C2890&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Weight lifting helps keep the bones strong.</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/active-senior-woman-working-exercise-gym-641129533">Liderina/ Shutterstock</a></span></figcaption></figure><p>Just as our muscles lose strength as we get older, so do our bones. This can have a serious effect on our lifestyle, and boosts risk of fractures – which are linked with an <a href="https://link.springer.com/article/10.1007/s00198-009-0920-3">increased risk of death</a>. Fortunately, just as we can build the strength in our muscles, we can build strength in our bones. </p>
<p>Bones are far more than a simple scaffold within our bodies. Bone is a complex organ which comes in a multitude of shapes and sizes. It’s made up of a diverse mixture of <a href="https://www.niams.nih.gov/health-topics/what-bone#:%7E:text=Bone%20is%20made%20of%20protein,the%20bone%20can%20resist%20breaking.">organic and inorganic components</a> – such as collagen and calcium. Combined together, these components create a structure that’s malleable enough that muscle can pull against it so we can move, while simultaneously being strong enough to protect critical organs. </p>
<p>Bone is not the solid, immovable, permanent structure that many might assume it to be. Healthy, living bone remains strong because it’s constantly being turned over, with old and damaged bone being excavated out and replaced with <a href="https://www.ncbi.nlm.nih.gov/books/NBK45513/">fresh bone</a>. </p>
<p>This internal quality control sees our skeleton being replaced <a href="https://www.ncbi.nlm.nih.gov/books/NBK45504/#ch2.s4">approximately every ten years</a> in healthy people – though this is slower in people who are older or sick. Certain health conditions can also cause excessive bone loss – such as cancer and hormonal changes during the menopause.</p>
<p>Unlike many other tissues, such as cartilage, tendon and muscle – where only a small number of different cell types occur – bone is comprised of a multitude of different cells. These include bone cells, immune cells, fat cells, nerve cells and blood cells, to name a few.</p>
<p>The combined action of these <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3341892/#:%7E:text=Bone%20is%20composed%20of%20four,mesenchymal%20cells%20called%20progenitor%20cells.">cell types</a> help our body maintain adequate bone volume throughout life, so we can continue to be active. </p>
<p><a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4515490/">Specialised bone cells</a> (called osteoblasts and osteoclasts) help modify our bones to repair damage and increase volume depending on the demands placed on them. So a tennis player who repeatedly serves with the same arm will have higher bone volume in their serving arm as a result.</p>
<h2>Looking after your bones</h2>
<p>Maintaining your bones throughout life is essential for good health and wellbeing. A sudden loss in mobility as a result of fracture has considerable knock-on effects to lifestyle – where walking around the shops, visiting friends and performing even the smallest daily tasks around the house can be painful. </p>
<p>Bone density (strength) can be preserved no matter your age with good diet and exercise. </p>
<figure class="align-center ">
<img alt="An array of calcium-rich foods, including milk, cheese, sardines and broccoli." src="https://images.theconversation.com/files/548526/original/file-20230915-17-h3uv76.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/548526/original/file-20230915-17-h3uv76.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/548526/original/file-20230915-17-h3uv76.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/548526/original/file-20230915-17-h3uv76.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/548526/original/file-20230915-17-h3uv76.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/548526/original/file-20230915-17-h3uv76.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/548526/original/file-20230915-17-h3uv76.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Calcium is important for bone strength.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/foods-rich-calcium-such-sardines-bean-366258461">Evan Lorne/ Shutterstock</a></span>
</figcaption>
</figure>
<p>A balanced diet rich in calcium (a crucial mineral within your bone) is recommended. Aim to consume <a href="https://www.nhs.uk/conditions/vitamins-and-minerals/calcium/">700mg a day</a>. Milk, yoghurt and cheese are all great sources of calcium. If you’re vegan, foods such as tofu, beans and lentils all contain calcium. You may need to take a supplement if you aren’t able to get the <a href="https://www.sciencedirect.com/science/article/pii/S0261561420306567#bib5">recommended amount</a> of calcium in your diet.</p>
<p>Importantly, our bodies need vitamin D to fully absorb <a href="https://pubmed.ncbi.nlm.nih.gov/3012979/#:%7E:text=Vitamin%20D%20functions%20by%20stimulating,intestine%2C%20require%20the%20parathyroid%20hormone.">calcium</a>, so spending time outside is key as our skin makes vitamin D when exposed to the sun. Try to get up to ten minutes twice a day. In the winter, when there tends to be less sunlight, you may want to consider a vitamin D supplement.</p>
<p>Exercise is another way you can keep bones strong – specifically <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6323511/">weight-bearing exercises</a>. Walking and climbing the stairs are great options to begin with if you don’t regularly exercise. But more rigorous activities – such as jumping rope or weight training – are better, as they stimulate more bone growth. This is because when the muscles pull hard on the attached bone, it <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6279907/">stimulates growth</a>.</p>
<p>These kinds of exercises can be done by anyone of any age. Just be sure to adapt the exercise you do to your fitness level and ability. It’s also recommended you gradually build up the amount you exercise to avoid injury.</p>
<p>Reducing pollutants in your body (such as <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5352985/">smoking</a> and <a href="https://link.springer.com/article/10.1007/s00198-011-1787-7">alcohol</a>) will also help give your bone cells the best chance of working properly throughout life. </p>
<p>If you’re concerned about how strong your bones are – or if you have certain health conditions that may decrease your bone mineral density (<a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6288610/#:%7E:text=Patients%20with%20gastrointestinal%20disease%20(GI,overlook%20this%20fact%20in%20practice.)">such as</a> coeliac disease, inflammatory bowel disease, <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5349336/">diabetes</a> and <a href="https://www.cancer.net/coping-with-cancer/physical-emotional-and-social-effects-cancer/managing-physical-side-effects/osteoporosis#:%7E:text=Cancer%20can%20contribute%20to%20bone,treatments%20can%20make%20it%20worse.">cancer</a>) – you can always speak to your GP about your concerns. They will be able to give you personalised advice on the best ways of looking after your bones.</p><img src="https://counter.theconversation.com/content/212743/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>James Edwards receives funding from a variety of government, charity and industry-related sources. </span></em></p>Our skeleton is replaced approximately every ten years to ensure our bones stay strong and healthy.James Edwards, Associate Professor of the Oxford Skeletal Ageing and Regeneration Group, University of OxfordLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2073832023-06-22T13:38:35Z2023-06-22T13:38:35ZFull-fat or low-fat cheese and milk? A dietitian on which is better<figure><img src="https://images.theconversation.com/files/532750/original/file-20230619-1823-uf7sp3.jpg?ixlib=rb-1.1.0&rect=16%2C114%2C5447%2C3522&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Are low-fat dairy products really better for us?</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/young-woman-slice-cheese-her-hand-2056001120">Bernardo Emanuelle/Shutterstock</a></span></figcaption></figure><hr>
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<p><em>You can listen to more articles from The Conversation, narrated by Noa, <a href="https://theconversation.com/us/topics/audio-narrated-99682">here</a>.</em></p>
<hr>
<p>When it comes to dairy products do you tend to buy full-fat or low-fat products? For many people, going for low-fat options can seem like the “healthier” choice. </p>
<p>Indeed, a <a href="https://foodinsight.org/consumer-survey-purchasing-behaviors-eating-decisions-and-health-perceptions-of-dietary-fats-and-oils/">2020 survey</a> in the US found that out of 1,000 people questioned, one in three sought out “low fat” or “reduced fat” foods or drinks, with dairy being the most common food category for low–fat options. But is low-fat milk, cheese, yoghurt and butter really any better for us?</p>
<p>Many governments and public health bodies recommend dairy as a <a href="https://journals.lww.com/nutritiontodayonline/fulltext/2008/11000/Role_of_Dairy_Foods_in_the_Dietary_Guidelines.3.aspx?casa_token=y8APLahFjikAAAAA:fDX-SfWQ2mxKll7omZN0CYiSEwE04-DmCt43jks8deC_VCsPXRoRWiKDTyR_xK43yM9T2aVeW7f_djSoG0xkvu-MH1w">key part</a> of a healthy diet (although it’s perfectly possible to be healthy without it, as many people around the world are). And many people opt for low-fat options as part of this. </p>
<p>Low-fat milk is made by removing or skimming the cream off the milk. So you can get whole or full-fat milk (3.5% fat), semi-skimmed or half-fat milk (1.8% fat) or fully skimmed milk (0.1%-0.3% fat). </p>
<p>The same process can be used to make lower-fat cheeses and yoghurts. However, removing fat can affect how cheese dries and how flavours develop during maturing.</p>
<p>Most relevant dietary guidelines encourage the consumption of low-fat dairy foods, except for in very young children. But a recent <a href="https://academic.oup.com/advances/article/11/4/928/5760740?login=false">review</a> of the available research found that children who consumed full-fat dairy foods were healthier and leaner than those who consumed reduced-fat versions. </p>
<p>It could be that families who tend to have a history of living with health issues relating to diet or higher body weight may be more likely to eat low-fat products. An alternative view is that full-fat dairy products might be more filling and help with the regulation of appetite, meaning people eat less overall. </p>
<p>Either way, these observations in children have also been seen in <a href="https://academic.oup.com/advances/article/10/5/917S/5569504?login=false">adults</a>. </p>
<h2>Explaining the science</h2>
<p>It’s not just that low-fat dairy foods may not be better for our health. There is increasing evidence that some of the fatty acids found in dairy fats might actually reduce our risk of developing <a href="https://link.springer.com/article/10.1007/s11883-018-0724-z">heart disease</a> and <a href="https://www.sciencedirect.com/science/article/pii/S0261561421002934">type 2 diabetes</a>. </p>
<p>Indeed, it seems that higher intakes of <a href="https://link.springer.com/article/10.1007/s00394-017-1556-2">fermented dairy products</a> like unsweetened full-fat yoghurt and some cheeses might be associated with lower risks of heart disease and type 2 diabetes.</p>
<figure class="align-center ">
<img alt="Low-fat milk pile in supermarket" src="https://images.theconversation.com/files/532753/original/file-20230619-23-ztdomo.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/532753/original/file-20230619-23-ztdomo.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/532753/original/file-20230619-23-ztdomo.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/532753/original/file-20230619-23-ztdomo.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/532753/original/file-20230619-23-ztdomo.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/532753/original/file-20230619-23-ztdomo.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/532753/original/file-20230619-23-ztdomo.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Could low-fat be worse for you than whole milk?</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/los-angeles-california-united-states-09012020-1814166020"> The Image Party/Shutterstock</a></span>
</figcaption>
</figure>
<p>When it comes to the recommendation to eat reduced-fat dairy foods, the Australian guidelines seem to be based on a <a href="https://www.health.gov.au/sites/default/files/australian-dietary-guidelines.pdf">mathematical decision</a> around how calories add up to meet the recommended calorie intake for an average adult. </p>
<p>It’s unclear if this is the same for the guidelines in other countries, as elsewhere the detailed evidence has not been published in the same way. But it may well be that other recommendations to use lower-fat dairy products are based more on maths than science. </p>
<p>It’s also worth noting that the potential health benefits linked to dairy foods do not extend to butter and possibly not milk either, but are largely linked to intakes of <a href="https://link.springer.com/article/10.1007/s00394-017-1556-2">yoghurt and some types of cheese</a>.</p>
<p>There’s also <a href="https://twitter.com/KenDBerryMD/status/1086679359719698433">a myth</a> that low-fat milk and cheese can lead to weight gain, but this is false. It appears to be based on historical farming practices that used leftover <a href="https://library.dpird.wa.gov.au/cgi/viewcontent.cgi?article=3923&context=journal_agriculture4">skimmed milk from making cream to fatten piglets</a>.</p>
<h2>Low-fat v full-fat</h2>
<p>So, given the minimal evidence, why do so many healthy eating guidelines – including in the <a href="https://www.nhs.uk/live-well/eat-well/food-guidelines-and-food-labels/the-eatwell-guide/">UK</a>, <a href="https://www.dietaryguidelines.gov/sites/default/files/2020-12/Dietary_Guidelines_for_Americans_2020-2025.pdf">US</a> and <a href="https://www.eatforhealth.gov.au/guidelines/australian-guide-healthy-eating">Australia</a> – recommend that we choose low-fat or reduced-fat versions of dairy products? </p>
<p>Research has found that higher intakes of saturated fatty acids are linked to an increased risk of <a href="https://www.heart.org/en/healthy-living/healthy-eating/eat-smart/fats/saturated-fats#:%7E:text=The%20American%20Heart%20Association%20recommends,of%20saturated%20fat%20per%20day.">heart disease</a>, type 2 diabetes and <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1140705/#:%7E:text=The%20Chicago%20study%20reported%20the,by%202%20to%203%20times.">dementia</a>. </p>
<p>But this research looks at saturated fatty acids in general and not specifically saturated fatty acids found in dairy products, which have been shown in both <a href="https://academic.oup.com/advances/article/11/4/928/5760740?login=false">children</a> and <a href="https://academic.oup.com/advances/article/11/3/533/5697079?login=false">adults</a> to be potentially beneficial for our health. This is thought to be to do with the way these foods are fermented. </p>
<p>So these recommendations may come as part of suggestions to limit overall fat intake more broadly, rather than because full-fat dairy is “bad” for us.</p>
<p>Switching from full-fat milk to semi-skimmed milk in tea (up to five cups a day) is likely to save the average person less than 50kcal per day. This means, even when considering calories and energy, the effect of <a href="https://theconversation.com/dietary-guidelines-dont-work-heres-how-to-fix-them-68803">reducing fat is minimal</a>. </p>
<p>So if you consume dairy products, it’s likely that there’s no need to worry too much about the fat content. This is especially the case when it comes to unsweetened yoghurt and cheese, which when consumed in their full-fat form do seem to come with potential health benefits.</p><img src="https://counter.theconversation.com/content/207383/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Duane Mellor is a member of the British Dietetic Association</span></em></p>A recent evidence review found children who ate full-fat dairy were healthier and leaner.Duane Mellor, Lead for Evidence-Based Medicine and Nutrition, Aston Medical School, Aston UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1983452023-02-02T12:23:35Z2023-02-02T12:23:35ZVitamins and supplements: what you need to know before taking them<figure><img src="https://images.theconversation.com/files/507046/original/file-20230130-20-x1ljxi.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Supitcha McAdam/Shutterstock </span></span></figcaption></figure><p>If you were to open your medicine cabinet right now, there’s a fair chance that you’d find at least one bottle of vitamins alongside the painkillers, plasters and cough syrup.</p>
<p>After all, people are definitely buying vitamins: in 2020, the global market for complementary and alternative medicines, which includes multivitamin supplements, had an estimated value of <a href="https://www.grandviewresearch.com/industry-analysis/complementary-alternative-medicine-market">US$82.27 billion</a>. The use of natural health products such as minerals and amino acids has <a href="https://journals.lww.com/nutritiontodayonline/Abstract/2007/03000/Why_People_Use_Vitamin_and_Mineral_Supplements.4.aspx">increased</a> – and continues to rise, partly driven by consumers’ buying habits during the COVID-19 pandemic.</p>
<p>People <a href="https://www.businesslive.co.za/bd/companies/healthcare/2021-02-08-native-sales-of-sas-vitamins-and-nutritional-supplements-boom/">sought out</a> vitamins C and D, as well as zinc supplements, as potential preventive measures against the virus – even though the <a href="https://www.health.harvard.edu/blog/do-vitamin-d-zinc-and-other-supplements-help-prevent-covid-19-or-hasten-healing-2021040522310">evidence</a> for their efficacy was, and <a href="https://pubmed.ncbi.nlm.nih.gov/35888660/#:%7E:text=Concluding%2C%20available%20data%20on%20the,trials%20(RCTs)%20are%20inconsistent">remains</a>, inconclusive. </p>
<p>Multivitamins and mineral supplements are easily accessible to consumers. They are often marketed for their health claims and benefits – sometimes unsubstantiated. But their potential adverse effects are not always stated on the packaging.</p>
<p>Collectively, vitamins and minerals are known as micronutrients. They are essential elements needed for our bodies to function properly. Our bodies can only produce micronutrients in small amounts or not at all. We get the bulk of these nutrients <a href="https://www.iprjb.org/journals/index.php/IJF/article/view/1024">from our diets</a>. </p>
<p>People usually buy micronutrients to protect against disease or as dietary “insurance”, in case they are not getting sufficient quantities from their diets. </p>
<p>There’s a common perception that these supplements are harmless. But they can be dangerous at incorrect dosages. They provide a false sense of hope, pose a risk of drug interactions – and can delay more effective treatment. </p>
<h2>Benefits</h2>
<p>Vitamins are beneficial if taken for the correct reasons and as prescribed by your doctor. For example, folic acid supplementation in pregnant women has been shown to prevent neural tube defects. And individuals who reduce their intake of red meat without increasing legume consumption require a vitamin B6 supplement. </p>
<p>But a worrying trend is increasing among consumers: intravenous vitamin therapy, which is often punted by celebrities and social media marketing. Intravenous vitamins, nutrients and fluids are administered at pharmacies as well as beauty spas, and more recently “<a href="https://www.health.harvard.edu/blog/drip-bar-should-you-get-an-iv-on-demand-2018092814899">IV bars</a>”. Users believe these treatments can quell a cold, slow the effects of ageing, brighten skin, fix a hangover or just make them feel well. </p>
<p>Intravenous vitamin therapy was previously only used in medical settings to help patients who could not swallow, needed fluid replacements or had an electrolyte imbalance. </p>
<p>However, the evidence to support other benefits of intravenous vitamin therapy is limited. No matter how you choose to get additional vitamins, there are risks. </p>
<h2>Warning bells</h2>
<p>Most consumers use multivitamins. But others take large doses of single nutrients, especially vitamin C, iron and calcium. </p>
<p>As lecturers in pharmacy practice, we think it’s important to highlight the potential adverse effects of commonly used vitamins and minerals: </p>
<ul>
<li><p><a href="https://www.hsph.harvard.edu/nutritionsource/vitamin-a/">Vitamin A/retinol</a> is beneficial in maintaining good eye health. But it can cause toxicity if more than 300,000IU (units) is ingested. Chronic toxicity (hypervitaminosis) has been <a href="https://www.ncbi.nlm.nih.gov/books/NBK532916/">associated</a> with doses higher than 10,000IU a day. Symptoms include liver impairment, loss of vision and intracranial hypertension. It can cause birth defects in pregnant women.</p></li>
<li><p><a href="https://www.hsph.harvard.edu/nutritionsource/niacin-vitamin-b3/">Vitamin B3</a> is beneficial for nervous and digestive system health. At moderate to high doses it can cause peripheral vasodilation (widening or dilating of the blood vessels at the extremities, such as the legs and arms), resulting in skin flushing, burning sensation, pruritis (itchiness of the skin) and hypotension (low blood pressure). </p></li>
<li><p><a href="https://www.hsph.harvard.edu/nutritionsource/vitamin-b6/">Vitamin B6</a> is essential for brain development and in ensuring that the immune system remains healthy. But it can result in damage to the peripheral nerves, such as those in the hands and feet (causing a sensation of numbness and often referred to as pins and needles) at doses over 200mg/daily.</p></li>
<li><p><a href="https://www.hsph.harvard.edu/nutritionsource/vitamin-c/">Vitamin C</a> is an antioxidant and assists in the repair of body tissue. Taken in high doses it can cause kidney stones and interactions with drugs, such as the oncology drugs doxorubicin, methotrexate, cisplatin and vincristine. </p></li>
<li><p><a href="https://www.hsph.harvard.edu/nutritionsource/vitamin-d/">Vitamin D</a> is essential for bone and teeth development. At high doses it can cause hypercalcaemia (calcium level in the blood is above normal) that results in thirst, excessive urination, seizures, coma and death.</p></li>
<li><p><a href="https://www.hsph.harvard.edu/nutritionsource/calcium/#:%7E:text=Calcium%20is%20a%20mineral%20most,heart%20rhythms%20and%20nerve%20functions">Calcium</a> is essential for bone health, but can cause constipation and gastric reflux. High doses can cause hypercalciuria (increased calcium in the urine), kidney stones and secondary hypoparathyroidism (underactive parathyroid gland). It can have drug interactions with zinc, magnesium and iron. </p></li>
<li><p><a href="https://www.hsph.harvard.edu/nutritionsource/magnesium/">Magnesium</a> is important for muscle and nerve functioning. At high doses it can cause diarrhoea, nausea and abdominal cramping, and can interact with tetracyclines (antibiotics).</p></li>
<li><p>Zinc <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7781367/">can impair</a> taste and smell, and doses over 80mg daily have been <a href="https://link.springer.com/article/10.1007/s10654-022-00922-0#:%7E:text=Zinc%20supplementation%20of%20more%20than,zinc%20supplements%20among%20adult%20men.">shown</a> to have adverse prostate effects.</p></li>
<li><p><a href="https://www.hsph.harvard.edu/nutritionsource/selenium/">Selenium</a> can cause hair and nail loss or brittleness, lesions of the skin and nervous system, skin rashes, fatigue and mood irritability at high doses.</p></li>
<li><p><a href="https://www.sciencedirect.com/science/article/pii/S0098299720300364#:%7E:text=Expert%20guidelines%20for%20oral%20iron%20supplementation&text=Traditionally%2C%20the%20recommended%20daily%20dose,iron%20(Brittenham%2C%202018).">Iron</a> at 100-200mg/day can cause constipation, black faeces, black discoloration of teeth and abdominal pain.</p></li>
</ul>
<h2>Recommendations</h2>
<p>People need to make <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8377299/">informed decisions</a> based on evidence before consuming health products. </p>
<p>Regular exercise and a well-balanced diet are more likely to do us good, as well as being lighter on the pocket.</p>
<p>Seeking advice from a healthcare professional before consuming supplements can reduce the risk of adverse effects.</p>
<p>Be aware of the potential adverse effects of vitamins and seek a healthcare professional’s guidance if you have symptoms.</p><img src="https://counter.theconversation.com/content/198345/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>The authors do not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and have disclosed no relevant affiliations beyond their academic appointment.</span></em></p>There’s a common perception that supplements are harmless. But they can be dangerous at incorrect dosages.Neelaveni Padayachee, Senior Lecturer, Department of Pharmacy and Pharmacology, University of the WitwatersrandVarsha Bangalee, Associate Professor, Pharmaceutical Sciences, University of KwaZulu-NatalLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1833912022-05-20T09:59:02Z2022-05-20T09:59:02ZPlant-based milk products: what you need to know before making the switch<figure><img src="https://images.theconversation.com/files/464463/original/file-20220520-15-t00qfr.jpg?ixlib=rb-1.1.0&rect=8%2C8%2C5599%2C3724&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Plant-based milk alternatives may not contain the same nutrients as cow's milk.</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/dairy-free-milk-drink-ingredients-breakfast-1762870238">matka_Wariatka/ Shutterstock</a></span></figcaption></figure><p>Over the last decade, the number of people drinking cow’s milk has dropped – with people <a href="https://www.gov.uk/government/statistical-data-sets/family-food-datasets">swapping dairy</a> for plant-based alternatives, such as oat and almond milk. With <a href="https://theconversation.com/how-potato-milk-measures-up-against-other-plant-based-milk-alternatives-176938">new types of plant-based milks</a> seemingly emerging every week, this trend is unlikely to stop any time soon.</p>
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<p><em>You can listen to more articles from The Conversation, narrated by Noa, <a href="https://theconversation.com/uk/topics/audio-narrated-99682">here</a>.</em></p>
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<p>There are a number of reasons why people are making the switch from dairy to plant-based alternatives. For one, many people aren’t able to consume dairy. Not only are around <a href="https://onlinelibrary.wiley.com/doi/10.1111/j.1365-2036.2007.03557.x">5% of UK adults lactose intolerant</a>, dairy is also the <a href="https://ift.onlinelibrary.wiley.com/doi/abs/10.1111/1541-4337.12318">most common allergen</a> in early childhood.</p>
<p>Another major reason that people are switching to plant-based dairy alternatives is because of animal welfare and environmental concerns. Studies show that dairy milk produces more environmental emissions and requires more <a href="https://pubmed.ncbi.nlm.nih.gov/29853680/">land and water usage</a> than plant-based dairy alternatives.</p>
<p>But despite being marketed as alternatives to dairy, plant-based products may not be exactly the same as dairy. So if you’re thinking of making the switch, here are a few things to be aware of.</p>
<h2>Pay attention to nutrients</h2>
<p>Cow’s milk is a rich source of many important nutrients, such as protein, calcium, iodine and vitamin B12. But many plant-based dairy alternatives don’t naturally contain the same amount of these nutrients and micronutrients as dairy milk – if any at all.</p>
<p>On average, most plant-based alternatives contain almost no protein – while one glass of cow’s milk containing around eight grams of protein. Soya milk is the exception, containing a similar amount of protein per glass as dairy. </p>
<p>Protein is essential for healthy growth and development. While everyone needs protein, some groups may need more than others. For example, older adults need it to maintain muscle strength with ageing and children require it for growth.</p>
<p>On average, most UK adults get <a href="https://www.gov.uk/government/collections/national-diet-and-nutrition-survey">around 15% of their protein intake</a> from dairy products. But if plant-based dairy alternatives are used as like-for-like replacements, this number could be <a href="https://www.sciencedirect.com/science/article/abs/pii/S0963996921004853">less than 1.8%</a>. So if you do make the switch to plant-based dairy products, soya milk may be your best bet for getting protein. If you use other types of plant-based milk alternatives, it will be important to include other high-protein foods in your diet, such as tofu or eggs, to make sure you’re getting enough.</p>
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Read more:
<a href="https://theconversation.com/vegetarian-and-vegan-diet-five-things-for-over-65s-to-consider-when-switching-to-a-plant-based-diet-144088">Vegetarian and vegan diet: five things for over-65s to consider when switching to a plant-based diet</a>
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<p>Most plant-based dairy alternatives also don’t naturally contain the same vitamins and minerals that dairy does. As such, many need to have these added during the manufacturing process, which is called “fortification”. It’s worth noting, however, that any plant-based dairy alternatives labelled “organic” will not contain any fortified vitamins and minerals as this would go against regulations.</p>
<p>Calcium is a very important micronutrient found in milk. It’s needed for good bone health, particularly in children and adolescents. But my <a href="https://www.sciencedirect.com/science/article/abs/pii/S0963996921004853">own research has shown</a> that only 57% of milk alternatives, 63% of yogurt alternatives and 28% of cheese alternatives are fortified with calcium. So to ensure you’re <a href="https://www.bda.uk.com/resource/calcium.html">getting enough in your diet</a>, check the label and look for products that have been fortified with calcium. Or, focus on eating foods that contain calcium – such as fortified breads and cereals or tinned sardines or salmon. </p>
<figure class="align-center ">
<img alt="An opened can of tinned sardines." src="https://images.theconversation.com/files/464464/original/file-20220520-14-27imdv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/464464/original/file-20220520-14-27imdv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=399&fit=crop&dpr=1 600w, https://images.theconversation.com/files/464464/original/file-20220520-14-27imdv.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=399&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/464464/original/file-20220520-14-27imdv.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=399&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/464464/original/file-20220520-14-27imdv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=501&fit=crop&dpr=1 754w, https://images.theconversation.com/files/464464/original/file-20220520-14-27imdv.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=501&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/464464/original/file-20220520-14-27imdv.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=501&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Other food sources, such as tinned sardines, can help you get enough calcium in your diet.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/tin-can-sprats-sardines-top-view-244227574">Photosiber/ Shutterstock</a></span>
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</figure>
<p>Iodine is another <a href="https://www.bda.uk.com/resource/iodine.html">important nutrient</a>, especially for pregnant women and young children as it’s important for brain development. It also helps make thyroid hormones, which are important for both growth and metabolism. Despite milk and dairy products being the <a href="https://www.bda.uk.com/resource/iodine.html">main source of dietary iodine</a>, only a small handful of plant-based dairy products are fortified with iodine. Again, it’s important to read the product’s label to see if it’s been fortified with iodine or not. Otherwise, focus on eating foods that contain iodine, such as fish, shellfish or seaweed – or if this is not possible by taking a supplement.</p>
<p>Also look out for vitamin B12 in any plant-based dairy alternatives you may buy. This vitamin is essential for the brain, nerves and blood cells. While some plant-based dairy alternatives contain vitamin B12, most don’t, so you’ll need to focus on getting vitamin B12 from other food sources. Meat typically contains the highest levels of vitamin B12, but if you follow a vegetarian or vegan diet you may need to consume yeast extract, fortified breakfast cereals or supplements to make sure you’re getting enough. </p>
<h2>Other considerations</h2>
<p>Plant-based dairy alternatives aren’t cheap – costing almost <a href="https://www.sciencedirect.com/science/article/abs/pii/S0963996921004853?via%3Dihub">three times the price</a> of cow’s milk and other dairy products (such as yoghurt). For a family of two adults and one child, the cost of consuming dairy products is around £310.89 a year – while plant-based alternatives may cost closer to £856.70 a year. Purchasing own-brand products which are fortified may be a cheaper way to avoid dairy while sticking to a budget. </p>
<p>But of course, there are many reasons why a person may need to switch to plant-based dairy alternatives – whether that’s due to allergies or environmental concerns. If you’re worried about you or your child getting enough vitamins and minerals in your diet after <a href="https://www.bda.uk.com/resource/milk-allergy.html">making the switch</a> to plant-based alternatives, it’s worth consulting with a registered dietitian or doctor. Plant-based milks are generally not recommended for children under two years. After that, fortified soya milk is likely the best alternative as it will contain important vitamins and minerals, as well as high amounts of protein.</p>
<p>If you prefer other plant-based milk alternatives, look for one that’s fortified. Avoid rice drinks if you have children under the age of five as they may contain high levels of arsenic. But thanks to increasing interest in plant-based diets, there’s now a wealth of choice when it comes to plant-based dairy alternatives – just make sure you read the label before buying one.</p><img src="https://counter.theconversation.com/content/183391/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Miriam Clegg receives funding from the Medical Research Council, Biological Sciences Research Council, EIT Food, Horizon 2020, Apetito, and Tanita Healthy Weight Community Trust.</span></em></p>Look out for products fortified with important vitamins and minerals.Miriam Clegg, Associate Professor in Human Nutrition, University of ReadingLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1654662022-02-08T19:08:13Z2022-02-08T19:08:13ZDon’t drink milk? Here’s how to get enough calcium and other nutrients<figure><img src="https://images.theconversation.com/files/444932/original/file-20220208-26-4g1zsj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/asian-girl-drinking-milk-beverage-grow-429610183">Shutterstock</a></span></figcaption></figure><p>Cow’s milk is an <a href="https://pubmed.ncbi.nlm.nih.gov/33920532/">excellent source of calcium</a> which, along with vitamin D, is needed to <a href="https://www.bones.nih.gov/health-info/bone/osteoporosis/bone-mass">build strong, dense bones</a>. </p>
<p><a href="https://www.betterhealth.vic.gov.au/health/healthyliving/milk#nutrients-in-milk">Milk also contains</a> protein, the minerals phosphorus, potassium, zinc and iodine, and vitamins A, B2 (riboflavin) and B12 (cobalamin). </p>
<p>As a child I drank a lot of milk. It was delivered in pint bottles to our front steps each morning. I also drank a third of a pint before marching into class as part of the <a href="https://education.qld.gov.au/about-us/history/history-topics/free-milk-scheme#:%7E:text=Teachers%20and%20children%20of%20the,into%20the%20bottle%20was%20challenging.">free school milk program</a>. I still love milk, which makes getting enough calcium easy. </p>
<p>Of course, many people <a href="https://nutrition.org/going-nuts-about-milk-heres-what-you-need-to-know-about-plant-based-milk-alternatives/">don’t drink milk</a> for a number of reasons. The good news is you can get all the calcium and other nutrients you need from other foods. </p>
<h2>What foods contain calcium?</h2>
<p><a href="https://www.betterhealth.vic.gov.au/health/healthyliving/calcium#good-sources-of-calcium">Dairy products such as cheese and yoghurt</a> are rich in calcium, while non-dairy foods including tofu, canned fish with bones, green leafy vegetables, nuts and seeds contain varying amounts. </p>
<p>Some foods are fortified with added calcium, including some breakfast cereals and soy, rice, oat and nut “milks”. Check their food label <a href="https://nomoneynotime.com.au/hacks-myths-faqs/how-to-decode-food-labels">nutrition information panels</a> to see how much calcium they contain.</p>
<p>However, it’s <a href="https://pubmed.ncbi.nlm.nih.gov/35011055/">harder for your body to absorb calcium</a> from non-dairy foods. Although your body does get better at absorbing <a href="https://pubmed.ncbi.nlm.nih.gov/34281429/">calcium from plant foods</a>, and also when <a href="https://pubmed.ncbi.nlm.nih.gov/15068499/">your total calcium intake is low</a>, the overall effect means if you don’t have dairy foods, you may need to eat more foods that contain calcium to maximise your bone health. </p>
<figure class="align-center ">
<img alt="Healthy tofu stirfry with leafy greens." src="https://images.theconversation.com/files/444946/original/file-20220208-25-tm13jp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/444946/original/file-20220208-25-tm13jp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/444946/original/file-20220208-25-tm13jp.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/444946/original/file-20220208-25-tm13jp.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/444946/original/file-20220208-25-tm13jp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/444946/original/file-20220208-25-tm13jp.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/444946/original/file-20220208-25-tm13jp.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Tofu is just one source of calcium.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/nutritious-okinawan-tofu-vegetable-stirfry-set-1981809443">Shutterstock</a></span>
</figcaption>
</figure>
<h2>How much calcium do you need?</h2>
<p>Depending on your age and sex, the <a href="https://www.nrv.gov.au/nutrients/calcium">daily calcium requirements</a> vary from 360 milligrams per day to more than 1,000 mg for teens and older women. </p>
<p>One 250ml cup of cow’s milk contains about 300mg of calcium, which is equivalent to one standard serve. This <a href="https://www.eatforhealth.gov.au/food-essentials/five-food-groups/milk-yoghurt-cheese-andor-their-alternatives-mostly-reduced-fat">same amount is found in</a>:</p>
<ul>
<li>200 grams of yoghurt</li>
<li>250 ml of calcium-fortified plant milks </li>
<li>100 grams of canned pink salmon with bones</li>
<li>100 grams of firm tofu</li>
<li>115 grams of <a href="https://www.nutsforlife.com.au/resource/almonds/">almonds</a>.</li>
</ul>
<p>The <a href="https://www.eatforhealth.gov.au/food-essentials/how-much-do-we-need-each-day/recommended-number-serves-adults">recommended number of daily serves</a> of dairy and non-dairy alternatives varies: </p>
<ul>
<li><p>children <a href="https://www.eatforhealth.gov.au/food-essentials/how-much-do-we-need-each-day/recommended-number-serves-children-adolescents-and">should have</a> between 1 and 3.5 serves a day, depending on their age and sex </p></li>
<li><p>women aged 19 to 50 should have 2.5 serves a day, then 4 serves when aged over 50</p></li>
<li><p>men aged 19 to 70 should have 2.5 serves a day, then 3.5 serves when aged over 70. </p></li>
</ul>
<p>However, the <a href="https://www.abs.gov.au/ausstats/abs@.nsf/Lookup/by%20Subject/4364.0.55.012%7E2011-12%7EMain%20Features%7EMilk,%20yoghurt,%20cheese%20and%20alternatives%7E17">average Australian intake</a> is just 1.5 serves per day, with only one in ten <a href="https://www.eatforhealth.gov.au/food-essentials/five-food-groups/milk-yoghurt-cheese-andor-their-alternatives-mostly-reduced-fat">achieving the recommendations</a>. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/soy-oat-almond-rice-coconut-dairy-which-milk-is-best-for-our-health-146869">Soy, oat, almond, rice, coconut, dairy: which 'milk' is best for our health?</a>
</strong>
</em>
</p>
<hr>
<h2>What other nutrients do you need?</h2>
<p>If you don’t drink milk, the challenge is getting enough nutrients to have a balanced diet. Here’s what you need and why. </p>
<p><strong>Protein</strong></p>
<p><em>Food sources: meat, poultry, fish, eggs, nuts, seeds, legumes, dried beans and tofu.</em></p>
<p>Needed for growth and repair of cells and to make antibodies, enzymes and make specific transport proteins that carry chemical massages throughout the body.</p>
<p><strong>Phosphorus</strong></p>
<p><em>Food sources: meat, poultry, seafood, nuts, seeds, wholegrains, dried beans and lentils.</em></p>
<p>Builds bone and teeth, supports growth and repair of cells, and is needed for energy production.</p>
<figure class="align-center ">
<img alt="Whole grain loaf of bread." src="https://images.theconversation.com/files/444950/original/file-20220208-20-ri7mnm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/444950/original/file-20220208-20-ri7mnm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=282&fit=crop&dpr=1 600w, https://images.theconversation.com/files/444950/original/file-20220208-20-ri7mnm.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=282&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/444950/original/file-20220208-20-ri7mnm.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=282&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/444950/original/file-20220208-20-ri7mnm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=354&fit=crop&dpr=1 754w, https://images.theconversation.com/files/444950/original/file-20220208-20-ri7mnm.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=354&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/444950/original/file-20220208-20-ri7mnm.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=354&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Whole grains are a source of phosphorus, zinc and vitamin B12.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/top-view-sliced-wholegrain-bread-on-1084483424">Shutterstock</a></span>
</figcaption>
</figure>
<p><strong>Potassium</strong></p>
<p><em>Food sources: leafy green vegetables (spinach, silverbeet, kale), carrots, potatoes, sweet potatoes, pumpkin, tomatoes, cucumbers, zucchini, eggplant, beans and peas, avocados, apples, oranges and bananas.</em></p>
<p>Needed to activate cells and nerves. Maintains fluid balance and helps with muscle contraction and regulation of blood pressure.</p>
<p><strong>Zinc</strong></p>
<p><em>Food sources: lean meat, chicken, fish, oysters, legumes, nuts, wholemeal and wholegrain products.</em> </p>
<p>Helps with wound healing and the development of the immune system and other essential functions in the body, including taste and smell. </p>
<figure class="align-right ">
<img alt="Chick pea curry with brown rice." src="https://images.theconversation.com/files/444948/original/file-20220208-21-1gqlfwm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/444948/original/file-20220208-21-1gqlfwm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/444948/original/file-20220208-21-1gqlfwm.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/444948/original/file-20220208-21-1gqlfwm.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/444948/original/file-20220208-21-1gqlfwm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/444948/original/file-20220208-21-1gqlfwm.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/444948/original/file-20220208-21-1gqlfwm.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=754&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Legumes such as chick peas contain protein and zinc.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/indian-vegetarian-curry-potatoes-chickpeas-lentils-251307334">Shutterstock</a></span>
</figcaption>
</figure>
<p><strong>Iodine</strong></p>
<p><em>Food sources: fish, prawns, other seafood, iodised salt and commercial breads.</em></p>
<p>Needed for normal growth, brain development and used by the thyroid gland to make the hormone thyroxine, which is needed for growth and metabolism.</p>
<p><strong>Vitamin A</strong></p>
<p><em>Food sources: eggs, oily fish, nuts, seeds. (The body can also make vitamin A from beta-carotene in orange and yellow vegetables and green leafy vegetables.)</em></p>
<p>Needed for antibody production, maintenance of healthy lungs and gut, and for good vision.</p>
<p><strong>Vitamin B2 (riboflavin)</strong></p>
<p><em>Food sources: wholegrain breads and cereals, egg white, leafy green vegetables, mushrooms, yeast spreads, meat.</em></p>
<p>Needed to release energy from food. Also supports healthy eyesight and skin.</p>
<p><strong>Vitamin B12 (cobalamin)</strong></p>
<p><em>Food sources: meat, eggs and most foods of animal origin, some fortified plant milks and fortified yeast spreads (check the label).</em></p>
<p>Needed to make red blood cells, DNA (your genetic code), myelin (which insulate nerves) and some neurotransmitters needed for brain function. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/what-is-a-balanced-diet-anyway-72432">What is a balanced diet anyway?</a>
</strong>
</em>
</p>
<hr>
<h2>When might you need to avoid milk?</h2>
<p>Reasons <a href="https://nutrition.org/going-nuts-about-milk-heres-what-you-need-to-know-about-plant-based-milk-alternatives/">why people don’t drink milk</a> range from taste, personal preferences, animal welfare or environmental concerns. Or it could be due to health conditions or concerns about intolerance, allergy and acne. </p>
<p><strong>Lactose intolerance</strong> </p>
<p>Lactose is the main carbohydrate in milk. It’s broken down in the simple sugars by an enzyme in the small intestine called lactase. </p>
<p>Some people are <a href="https://www.betterhealth.vic.gov.au/health/conditionsandtreatments/lactose-intolerance">born without the lactase enzyme or their lactase levels decrease</a> as they age. For these people, consuming foods containing a lot of lactose means it passes undigested along the gut and can trigger symptoms such as bloating, pain and diarrhoea. </p>
<figure class="align-center ">
<img alt="Man holds his stomach after drinking a milky coffee." src="https://images.theconversation.com/files/444949/original/file-20220208-21-15rhf28.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/444949/original/file-20220208-21-15rhf28.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/444949/original/file-20220208-21-15rhf28.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/444949/original/file-20220208-21-15rhf28.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/444949/original/file-20220208-21-15rhf28.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/444949/original/file-20220208-21-15rhf28.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/444949/original/file-20220208-21-15rhf28.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Lactose intolerance can cause bloating and pain.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/white-man-dark-hair-sits-wooden-617367890">Shutterstock</a></span>
</figcaption>
</figure>
<p>Research shows <a href="https://pubmed.ncbi.nlm.nih.gov/20404262/">smalls amounts of lactose</a> – up to 15 grams daily – can be tolerated without symptoms, especially if spread out over the day. A cup of <a href="https://www.dairy.com.au/dairy-matters/you-ask-we-answer/what-is-the-lactose-content-of-different-dairy-products">cows milk contains about 16 grams of lactose</a>, while a 200g tub of yoghurt contains 10g, and 40g cheddar cheese contains less than 1g. </p>
<p><strong>Cow’s milk allergy</strong></p>
<p><a href="https://www.betterhealth.vic.gov.au/health/conditionsandtreatments/cows-milk-allergy">Cow’s milk allergy</a> occurs in <a href="https://pubmed.ncbi.nlm.nih.gov/31083388/">about 0.5-3% of one year olds</a>. By age five, about half are reported to have grown out of it, and 75% by adolescence. However, one survey found <a href="https://pubmed.ncbi.nlm.nih.gov/31083388/">9% of pre-school children</a> had severe allergy with <a href="https://www.allergy.org.au/patients/about-allergy/anaphylaxis">anaphylaxis</a>.</p>
<p>Symptoms of cow’s milk allergy include hives, rash, cough, wheeze, vomiting, diarrhoea or swelling of the face. </p>
<p>Symptom severity varies, and can happen immediately or take a few days to develop. If a reaction is severe, call 000, as it can be a medical emergency. </p>
<p><strong>Acne</strong> </p>
<p>The whey protein in cow’s milk products, aside from cheese, triggers an increase in insulin, a hormone that transports blood sugar, which is released into the blood stream. </p>
<p>Meanwhile, milk’s casein protein triggers an increase in another hormone, called <a href="https://en.wikipedia.org/wiki/Insulin-like_growth_factor_1">insulin-like growth factor</a> (IGF), which influences growth. </p>
<p>These two reactions promote the production of hormones called <a href="https://en.wikipedia.org/wiki/Androgen">androgens</a>, which can <a href="https://pubmed.ncbi.nlm.nih.gov/21034984/">lead to a worsening of acne</a>. </p>
<p>If this happens to you, then avoid milk, but keep eating hard cheese, and eat other foods rich in calcium regularly instead.</p>
<p>While milk can be problematic for some people, for most of us, drinking milk in moderation in line with recommendation is the way to go.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/is-milk-good-for-me-or-should-i-ditch-it-45764">Is milk good for me, or should I ditch it?</a>
</strong>
</em>
</p>
<hr>
<img src="https://counter.theconversation.com/content/165466/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Clare Collins is Laureate Professor in Nutrition and Dietetic at the University of Newcastle, NSW and a Hunter Medical Research Institute (HMRI) n affiliated researcher . She is a National Health and Medical Research Council (NHMRC) Leadership Fellow and has received research grants from NHMRC, ARC, MRFF, HMRI, Diabetes Australia, Heart Foundation, Bill and Melinda Gates Foundation, nib foundation, Rijk Zwaan Australia, WA Dept. Health, Meat and Livestock Australia, and Greater Charitable Foundation. She has consulted to SHINE Australia, Novo Nordisk, Quality Bakers, the Sax Institute, Dietitians Australia and the ABC. She was a team member conducting systematic reviews to inform the 2013 Australian Dietary Guidelines update and the Heart Foundation evidence reviews on meat and dietary patterns.</span></em></p>People who don’t drink milk can choose other foods to get the calcium, protein, vitamins and minerals their bodies need.Clare Collins, Laureate Professor in Nutrition and Dietetics, University of NewcastleLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1526522021-01-21T13:13:27Z2021-01-21T13:13:27ZInvasive tawny crazy ants have an intense craving for calcium – with implications for their spread in the US<figure><img src="https://images.theconversation.com/files/378340/original/file-20210112-23-1duz31c.png?ixlib=rb-1.1.0&rect=6%2C6%2C4019%2C3011&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Multiple queens ensure colonies have a steady output of workers.</span> <span class="attribution"><span class="source">Ryan Reihart</span>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span></figcaption></figure><p><em>The <a href="https://theconversation.com/us/topics/research-brief-83231">Research Brief</a> is a short take about interesting academic work.</em></p>
<h2>The big idea</h2>
<p>In a recent study, <a href="https://chelseprather.wordpress.com/">my colleagues</a> and <a href="https://scholar.google.com/citations?hl=en&user=6GBgzO8AAAAJ">I</a> discovered micronutrients in the ground <a href="https://www.doi.org/10.1002/ECY.3263">can control populations of invasive crazy ants</a> (<em>Nylanderia fulva</em>). </p>
<p>Tawny crazy ants – named for their fast, erratic movements – can blanket the ground by the millions. Originating in South America and now established in parts of the southern U.S., they <a href="https://www.nytimes.com/2013/12/08/magazine/crazy-ants.html">harm other insects, asphyxiate chickens and even short-circuit electronics in homes</a>. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/378389/original/file-20210112-23-1urj0n3.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Close up photo of a golden-colored ant against a blue background." src="https://images.theconversation.com/files/378389/original/file-20210112-23-1urj0n3.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/378389/original/file-20210112-23-1urj0n3.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=418&fit=crop&dpr=1 600w, https://images.theconversation.com/files/378389/original/file-20210112-23-1urj0n3.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=418&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/378389/original/file-20210112-23-1urj0n3.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=418&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/378389/original/file-20210112-23-1urj0n3.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=525&fit=crop&dpr=1 754w, https://images.theconversation.com/files/378389/original/file-20210112-23-1urj0n3.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=525&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/378389/original/file-20210112-23-1urj0n3.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=525&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">At only 0.125 inches (3.2 mm) long, crazy ants are tiny but mighty.</span>
<span class="attribution"><span class="source">Ryan Reihart</span>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
</figcaption>
</figure>
<p>Crazy ants are <a href="https://doi.org/10.1146/annurev.ecolsys.33.010802.150444">liquid feeders</a> <a href="https://doi.org/10.1653/024.096.0219">that consume nectar from plants – and honeydew (or secretions) from certain insects</a>. Ants crave these sugary resources, which <a href="https://doi.org/10.1073/pnas.1115263108">boost their colony growth</a>, enabling them to outcompete native species and ultimately spread. </p>
<p>The nutritional content of nectar and honeydew vary widely, however, <a href="https://www.britishecologicalsociety.org/ant-cravings-sugar-salt-vary-across-us/">depending on the nutrients available in a particular ecosystem</a>. There are 25 chemical elements required to build life – too much or too little of one may cause disease. So far, ecologists only really know about the importance of macronutrients, like nitrogen and phosphorus, that are abundant in living tissue. My team wanted to learn more about what micronutrients might be important to crazy ants.</p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/377606/original/file-20210107-20-1t2ehyf.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A man kneeling over a small hole dug in the grass." src="https://images.theconversation.com/files/377606/original/file-20210107-20-1t2ehyf.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/377606/original/file-20210107-20-1t2ehyf.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=801&fit=crop&dpr=1 600w, https://images.theconversation.com/files/377606/original/file-20210107-20-1t2ehyf.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=801&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/377606/original/file-20210107-20-1t2ehyf.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=801&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/377606/original/file-20210107-20-1t2ehyf.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1007&fit=crop&dpr=1 754w, https://images.theconversation.com/files/377606/original/file-20210107-20-1t2ehyf.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1007&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/377606/original/file-20210107-20-1t2ehyf.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1007&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Installing a pitfall trap in one of the 128 fertilized study plots.</span>
<span class="attribution"><span class="source">Kiersten Angelos</span>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
</figcaption>
</figure>
<p>We conducted a fertilization experiment at the <a href="http://www.eih.uh.edu/">University of Houston’s Coastal Center</a> and were able to demonstrate that the abundance of tawny crazy ants decreased 24% where there was more potassium and 45% where there was more sodium and potassium. </p>
<p>What greatly surprised our team was the discovery that ants were 13% more abundant in areas where there was more calcium – even in areas that had more sodium and potassium. This finding, <a href="https://www.doi.org/10.1002/ECY.3263">published in the journal Ecology</a>, could have big implications for the continued spread of crazy ants. </p>
<h2>Why it matters</h2>
<p>Ours is the first study showing calcium is important to an invasive ant, which is somewhat surprising given ants don’t have bones. It turns out, though, calcium is important in their <a href="https://doi.org/10.1016/j.ceca.2012.11.008">egg production</a>, <a href="https://doi.org/10.1080/00218839.2015.1035074">larval development</a> and <a href="https://doi.org/10.1093/aesa/51.2.142">physiological regulation</a>. </p>
<p><a href="https://doi.org/10.1002/ece3.1737">If the spread of crazy ants continues north</a>, the calcium-rich limestone bedrock of the lower U.S. Midwest may provide ideal conditions for populations to explode. Farmlands may be at risk because calcium is found in many fertilizers. Additionally, cities often have <a href="https://doi.org/10.1007/s10980-008-9288-6">more calcium than surrounding areas</a>, thanks to heavy cement use, limestone quarrying and destruction of buildings.</p>
<p>Tawny crazy ants not only are a major threat to the biodiversity and conservation of ecosystems but also <a href="https://doi.org/10.1038/ncomms12986">cost the U.S. billions of dollars in damage annually</a>. </p>
<h2>What still isn’t known</h2>
<p>Our results add to a small but <a href="https://doi.org/10.1111/geb.13196">growing list</a> <a href="https://doi.org/10.1111/ele.13517">of other experiments</a> <a href="https://doi.org/10.1111/ele.13127">that show the importance of micronutrients</a> to insects. </p>
<p>How far will tawny crazy ants make it in the United States? Will calcium influence their spread? Could other micronutrients like magnesium or iron be important to crazy ants?</p>
<p>In a world where <a href="https://doi.org/10.1126/science.1259855">humans are changing the “ingredients” of Earth’s surface soils</a> at an alarming rate, people may be unwittingly creating more favorable habitats for some invasive species. Figuring out which elements are most important to invasive species will be key to predicting, preventing and managing their spread.</p><img src="https://counter.theconversation.com/content/152652/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Ryan Reihart receives funding from the National Science Foundation (NSF) Division of Environmental Biology (DEB) grants 1457114 and 1724663 and from the University of Dayton Office for Graduate Academic Affairs through the Graduate Student Summer Fellowship Program. </span></em></p>The spread of tawny crazy ants may be driven, in part, by their need for calcium. The calcium-rich limestone bedrock of the lower U.S. Midwest may provide ideal conditions for populations to explode.Ryan Reihart, Teaching Assistant and Ph.D. Candidate of Ecology, University of DaytonLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1492292021-01-12T19:43:16Z2021-01-12T19:43:16ZAnti-nutrients – they’re part of a normal diet and not as scary as they sound<figure><img src="https://images.theconversation.com/files/377416/original/file-20210106-13-22nh6o.jpg?ixlib=rb-1.1.0&rect=109%2C97%2C4164%2C2670&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">These compounds occur naturally in a number of healthy foods, including legumes and whole grains.
</span> <span class="attribution"><a class="source" href="https://unsplash.com/s/photos/legumes-whole-grains">foodism360/Unsplash</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span></figcaption></figure><p>Maybe you’re trying to eat healthier these days, aiming to get enough of the good stuff and limit the less-good stuff. You’re paying attention to things like fiber and fat and vitamins… and anti-nutrients?</p>
<p>What the heck are anti-nutrients and are they something you need to be concerned about in your diet?</p>
<p>Let me, as a public health nutrition researcher, reassure you that anti-nutrients aren’t the evil nemesis of all the nutritious foods you eat. As long as you’re consuming a balanced and varied diet, anti-nutrients are not a concern. In fact, scientists are realizing they actually have many health benefits.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/377772/original/file-20210108-21-x8ovnm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="illustration of small intestine amid other organs" src="https://images.theconversation.com/files/377772/original/file-20210108-21-x8ovnm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/377772/original/file-20210108-21-x8ovnm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/377772/original/file-20210108-21-x8ovnm.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/377772/original/file-20210108-21-x8ovnm.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/377772/original/file-20210108-21-x8ovnm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/377772/original/file-20210108-21-x8ovnm.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/377772/original/file-20210108-21-x8ovnm.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Nutrients get absorbed into your bloodstream – or not – as digestion occurs in your small intestine.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/illustration/small-intestine-illustration-royalty-free-illustration/1190674194">Sebastian Kaulitzki/Science Photo Library via Getty Images</a></span>
</figcaption>
</figure>
<h2>What are anti-nutrients?</h2>
<p><a href="https://www.hsph.harvard.edu/nutritionsource/anti-nutrients/">Anti-nutrients are substances</a> that naturally occur in plant and animal foods.</p>
<p>The name comes from how they function in your body once you eat them. They <a href="https://www.sciencedirect.com/topics/food-science/antinutrients">block or interfere with how your body</a> <a href="https://doi.org/10.1631/jzus.B0710640">absorbs other nutrients</a> out of your gut and into your bloodstream so you can then use them. Thus, anti-nutrients may decrease the amount of nutrients you actually get from your food. They most commonly interfere with the absorption of <a href="https://doi.org/10.1016/j.jand.2016.09.025">calcium, iron, potassium, magnesium and zinc</a>.</p>
<p>Plants evolved these <a href="https://www.todaysdietitian.com/newarchives/070111p54.shtml">compounds as a defensive mechanism</a> against insects, parasites, bacteria and fungi. For example, some anti-nutrients can cause a food to taste bitter; animals won’t want to eat it, leaving the seed, for instance, to provide nourishment for future seedlings. Some anti-nutrients block the digestion of seeds that are eaten. The seeds disperse when they come out the other end in the animal’s fecal matter and can go on to grow new plants. Both of these survival tactics help the plant species grow and spread.</p>
<p>In terms of foods that people eat, you’ll most commonly find anti-nutrients naturally occurring in whole grains and legumes.</p>
<h2>Time for an image makeover as health enhancers</h2>
<p>Despite sounding scary, studies show that anti-nutrients are not of concern unless consumed in <a href="https://doi.org/10.1016/j.jcs.2014.01.010">ultra, unrealistically high amounts</a> – and they have numerous health benefits. </p>
<p>Anti-nutrients are currently undergoing a change in image very similar to the one dietary fiber experienced. At one point, scientists thought dietary fiber was bad for people. Since fiber could bind to nutrients and pull them out of the digestive tract in poop, it seemed like something to avoid. To address this perceived issue, grain processing in the late 1800s removed fiber from foods.</p>
<p>But now scientists know that <a href="https://doi.org/10.1111/j.1753-4887.2009.00189.x">dietary fiber is incredibly important</a> and encourage its consumption. Eating plenty of fiber lowers the risks of obesity, high blood pressure, heart disease, stroke, diabetes and some gastrointestinal diseases.</p>
<p>In the same way, rather than something to avoid, many anti-nutrients are now considered health-promoting nutraceuticals and functional foods due to their numerous benefits. Here’s an introduction to some of the most frequently eaten anti-nutrients that come with benefits:</p>
<ul>
<li><p><a href="https://doi.org/10.1089/109662004322984734">Saponins, common in legumes</a>, can boost the immune system, reduce risk of cancer, lower cholesterol, lower blood sugar response to foods, result in fewer cavities, reduce risk of kidney stones and combat blood clotting seen in heart attacks and strokes.</p></li>
<li><p><a href="https://doi.org/10.1016/j.jcs.2014.01.010">Lectins, found in cereal grains and legumes</a>, are associated with reduced risk of cardiovascular disease, diabetes, some cancers and becoming overweight or obese.</p></li>
<li><p><a href="https://doi.org/10.1080/10408699891274273">Tannins, commonly found in teas, coffees and processed meats and cheeses</a>, are antioxidants that can inhibit growth of bacteria, viruses, fungi and yeast and may decrease cholesterol levels and blood pressure.</p></li>
<li><p><a href="https://doi.org/10.1631/jzus.B0710640">Phytates, found in wheat, barley, rice and corn</a>, are associated with increased immune function and cancer cell death, as well as reduced cancer cell growth and spread. They also have antioxidant properties and can reduce inflammation. </p></li>
<li><p>Finally, <a href="https://doi.org/10.1024/0300-9831.72.1.26">glucosinates, found in brassica vegetables</a> like cauliflower, inhibit tumor cell growth.</p></li>
</ul>
<p>Oxalates are one of the few anti-nutrients with mostly negative impacts on the body. They are <a href="https://www.uofmhealth.org/health-library/aa166321">found in lots of common foods</a>, including legumes, beets, berries, cranberries, oranges, chocolate, tofu, wheat bran, soda, coffee, tea, beer, dark green vegetables and sweet potatoes. The negative impacts of oxalates include binding to calcium in the digestive tract and removing it from the body in bowel movements. Oxalates can also <a href="https://www.uofmhealth.org/health-library/aa166321">increase the risk of kidney stones</a> in some people.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/377773/original/file-20210108-21-17lbxqq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="bowl of chickpea curry" src="https://images.theconversation.com/files/377773/original/file-20210108-21-17lbxqq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/377773/original/file-20210108-21-17lbxqq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/377773/original/file-20210108-21-17lbxqq.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/377773/original/file-20210108-21-17lbxqq.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/377773/original/file-20210108-21-17lbxqq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/377773/original/file-20210108-21-17lbxqq.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/377773/original/file-20210108-21-17lbxqq.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Lots of healthy, tasty foods come with the added benefits of anti-nutrients.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/chickpea-and-spinach-curry-royalty-free-image/657152778">Joan Ransley/Moment via Getty Images</a></span>
</figcaption>
</figure>
<h2>Fitting anti-nutrients into a healthy diet</h2>
<p>Overall, comparing the benefits to the drawbacks, anti-nutrient pros actually outweigh the cons. The healthy foods that contain them – mainly fruits, vegetables, whole grains and legumes – should be encouraged not avoided.</p>
<p>Anti-nutrients become a concern only if these foods are consumed in ultra-high amounts, <a href="https://www.ars.usda.gov/research/project/?accnNo=426312">which is very unlikely</a> for most adults and children in the U.S. Additionally, a large proportion of anti-nutrients are removed or lost from foods people eat <a href="https://www.hsph.harvard.edu/nutritionsource/anti-nutrients/">as they’re processed and cooked</a>, especially if soaking, blanching, boiling or other high-heat processes are involved.</p>
<p>Vegetarians and vegans may be at higher risk of negative effects from anti-nutrients because their diet relies heavily on fruits, vegetables, whole grains and legumes. But these <a href="https://doi.org/10.1016/j.jand.2016.09.025">plant-based diets are still among the healthiest</a> and are associated with reduced risk of cardiovascular disease, obesity, diabetes and numerous types of cancers. </p>
<p>Vegetarians and vegans can take a few steps to help counteract anti-nutrients’ effects on their absorption of particular nutrients:</p>
<ul>
<li><p>Pair high iron <a href="https://doi.org/10.1093/jn/130.5.1378S">and zinc</a> <a href="https://doi.org/10.1016/bs.afnr.2014.11.003">foods with</a> <a href="https://doi.org/10.1093/ajcn/59.5.1233S">foods high in vitamin C</a> (examples: veggie meatballs with tomato sauce, tomato-based chili with beans).</p></li>
<li><p><a href="https://www.jblearning.com/catalog/productdetails/9780763779764?jblsearch">Soak legumes before cooking</a>. </p></li>
<li><p><a href="https://doi.org/10.1093/ajcn/70.3.543s">Time dairy intake</a> such that it is not always paired with high oxalate foods.</p></li>
<li><p>Purchase dairy products that are fortified with calcium.</p></li>
<li><p>Consider a multivitamin-mineral supplement with about 100% of the daily recommended dose of nutrients (check the nutrition facts panel) as nutrition insurance if you are worried, but be sure to talk to your doctor first.</p></li>
</ul>
<p>[<em>Get our best science, health and technology stories.</em> <a href="https://theconversation.com/us/newsletters/science-editors-picks-71/?utm_source=TCUS&utm_medium=inline-link&utm_campaign=newsletter-text&utm_content=science-best">Sign up for The Conversation’s science newsletter</a>.]</p><img src="https://counter.theconversation.com/content/149229/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Jill Joyce does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Anti-nutrients naturally occur in food and can block the amount of other nutrients available for your body to use. But their effects aren’t all bad, which is why they’re undergoing an image makeover.Jill Joyce, Assistant Professor of Public Health Nutrition, Oklahoma State UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1125742019-05-15T20:54:29Z2019-05-15T20:54:29ZCould the solution to osteoporosis be in the bile?<figure><img src="https://images.theconversation.com/files/270881/original/file-20190425-121228-jndadn.jpg?ixlib=rb-1.1.0&rect=0%2C17%2C5535%2C3759&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Osteoporosis affects one in three women, but men are also concerned.</span> <span class="attribution"><span class="source">Shutterstock</span></span></figcaption></figure><p>Osteoporosis is a degenerative disease where the bone density and quality are reduced. This disease is associated with substantial pain and disability leading to devastating long-term physical and psychological consequences. In Europe, the total osteoporosis economic burden was estimated at 30.7 billion euros in 2010, and is expected to reach <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4794536/#B74">76.7 billion in 2050</a>, based on changes in demography.</p>
<p>Osteoporosis is highly prevalent and actually affects one in three women over the age of 50. Over the next 50 years, the number of hip fracture is expected to more than double meaning that the prevalence of osteoporosis will continue to rise and become a significant burden on health-care systems and life quality, especially in women. </p>
<p>So far, efficient treatments for osteoporosis without any side effects and with optimal bioavailability are currently missing, making highly relevant the search of alternatives. The proposed research includes a pre-clinical phase to evaluate the use of bile acid analogues in a mouse model of menopause-induced osteoporosis. If this study is successful it could eventually lead to the development of pharmacological agents for this disease.</p>
<h2>The bone is a dynamic tissue</h2>
<p>The bone undergoes continuous remodeling to grow, heal and maintain metabolic demand (the bone is dynamically storing and releasing minerals in the form of calcium phosphate). This remodeling is carried out by two different cell types; the osteoblast, that are in charge of bone formation, and the osteoclast, which mediate bone resorption or break down. Osteoporosis is the result of an imbalance between bone formation and resorption. This imbalance reduces bone mass and quality, eventually leading to bone fracture, the main clinical manifestation of this disease. </p>
<p>Sterols (fat-like compounds that occur naturally in plants, animals, or fungi and exert multiple physiological roles in the cells), are major actors of bone remodeling processes. Among these sterols, œstrogen inhibits osteoclast formation (“differentiation”), therefore preventing bone resorption. It means that oestrogen deficiency, like the one observed during the menopause, can promote an accelerated bone turnover rate increasing the risk to develop osteoporosis.</p>
<h2>How bile acids affect bone tissues</h2>
<p>Bile acids are small metabolic molecules that are produced in the liver from another famous “sterol”, cholesterol. They are the main constituents of bile. After someone eats, bile acids are secreted into the intestinal lumen to participate in the absorption of dietary lipids by emulsifying them. During enterohepatic recirculation (their way back from the intestine to the liver), bile acids spill over in the systemic circulation and can reach every tissue in our body including the bone. </p>
<p>In addition to their lipid emulsifying function, bile acids are now considered versatile signaling molecules that can activate dedicated receptors and induce cellular responses. A growing body of evidence shows that bile acids regulate skeletal homeostasis (i.e., its relatively stable state of equilibrium of the skeleton) through direct effects on osteoblasts and osteoclasts. In particular, when added to osteoblast cell cultures some bile acid species are able to activate them and to promote bone mineralization.</p>
<p>If these results are confirmed in animals, these molecules could be good candidates for future drugs to treat osteoporosis. As an AXA-granted post-doctoral researcher at the School of Life Sciences of EPFL (Ecole Polytechnique Fédérale de Lausanne), my goal is to contribute, together with my research team, to the elucidation of the role of one of the main bile acid-signaling mediators in bone remodeling, the cell-surface receptor TGR5. </p>
<h2>TGR5, a central actor in osteoporosis</h2>
<p>Once bile acids link to TGR5, multiple metabolic responses take place. For example, TGR5 activation increases energy expenditure <a href="https://www.ncbi.nlm.nih.gov/pubmed/16400329">in brown adipose tissue and muscle</a>, decreases <a href="https://www.ncbi.nlm.nih.gov/pubmed/25365223">inflammation </a>, improves <a href="https://www.ncbi.nlm.nih.gov/pubmed/19723493">glucose metabolism</a> and <a href="https://www.ncbi.nlm.nih.gov/pubmed/22152303">inhibits atherosclerosis</a>. </p>
<p>Interestingly, our preliminary data indicated that TGR5 is also needed in order to maintain healthy bones. Indeed, when this receptor is genetically deleted in mice, their bone mass decreases, mimicking osteoporosis already at young age. Conversely, would it be possible to increase TGR5 activity in order to prevent osteoporosis?
In order to answer this question, our strategy includes the combination of in vitro (which means outside an alive organism, i.e., on cell cultures), in vivo (which means in living animals, i.e., mice) and in silico (which means in computer models) approaches. </p>
<p>In vitro, we will explore the role of TGR5 in osteoblast and osteoclast cell models. In vivo, we will test the efficacy of synthetic bile acid mimetics intended to activate TGR5 for the treatment of menopause-induced osteoporosis using mice whose ovaries have been removed to mimic the menopause conditions. In silico, we will apply bioinformatic tools to identify novel biomarkers that could be used for the prevention or early detection of this disease. Current biomarkers are of limited interest because their impairment indicates that the person has already developed the disease. They can be used to evaluate treatment response and disease progression, but they are useless for prevention. Our hope is that by comparing the genetic and metabolic profile of a mice population exhibiting a predisposition to develop osteoporosis with a normal population, we will identify an impairment of some enzymes or metabolites related to bile acid metabolism or function.</p>
<p>With this innovative investigation approach, we will contribute to a better understanding of the development of this pathology and to the increasing efforts for its prevention and treatment. These novel insights will provide a robust translational bridge to potential human applications in the context of osteoporosis.</p>
<hr>
<figure class="align-right ">
<img alt="" src="https://images.theconversation.com/files/202296/original/file-20180117-53314-hzk3rx.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/202296/original/file-20180117-53314-hzk3rx.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=121&fit=crop&dpr=1 600w, https://images.theconversation.com/files/202296/original/file-20180117-53314-hzk3rx.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=121&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/202296/original/file-20180117-53314-hzk3rx.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=121&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/202296/original/file-20180117-53314-hzk3rx.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=152&fit=crop&dpr=1 754w, https://images.theconversation.com/files/202296/original/file-20180117-53314-hzk3rx.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=152&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/202296/original/file-20180117-53314-hzk3rx.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=152&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption"></span>
</figcaption>
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<p><em>Created in 2007 to help accelerate and share scientific knowledge on key societal issues, the AXA Research Fund has been supporting nearly 600 projects around the world conducted by researchers from 54 countries. To learn more about this author’s research, visit her <a href="https://www.axa-research.org/en/projet/laura-velazquez">dedicated page</a> on the AXA Research Fund website.</em></p><img src="https://counter.theconversation.com/content/112574/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Laura Alejandra Velazquez Villegas a reçu des financements de AXA Research Fund, AXA postdoctoral fellowship on projects related to women’s health issues and women’s access to healthcare.</span></em></p>There is no treatment for osteoporosis, which affects millions of people and costs billions of euros every year. What if the solution was in the bile? Explanations.Laura Alejandra Velazquez Villegas, Research associate, EPFL – École Polytechnique Fédérale de Lausanne – Swiss Federal Institute of Technology in LausanneLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1077082019-04-30T20:13:26Z2019-04-30T20:13:26ZHave you gone vegan? Keep an eye on these 4 nutrients<figure><img src="https://images.theconversation.com/files/271649/original/file-20190430-194630-1afyvj1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Legumes are a good source of calcium.</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/healthy-homemade-chickpea-veggies-salad-jar-535446037?src=vLw9oCI1nLotsXy-87sbEw-1-34">Saschanti17/Shutterstock</a></span></figcaption></figure><p>There are <a href="https://veganuary.com/au/why/">many reasons</a> people go vegan, from wanting to be healthier, to reducing their environmental footprint, to concerns about animal welfare.</p>
<p>No matter what the reason, many people find it difficult to meet the <a href="https://www.nrv.gov.au/nutrients">nutrient intake targets</a> for specific vitamins and minerals while on a vegan diet. These include vitamin B12, iron, calcium, and iodine. </p>
<p>Here’s how to make sure you’re getting enough of these vitamins and minerals while following a vegan diet.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/vegan-diet-how-your-body-changes-from-day-one-100413">Vegan diet: how your body changes from day one</a>
</strong>
</em>
</p>
<hr>
<h2>1. Vitamin B12</h2>
<p><a href="https://www.nrv.gov.au/nutrients/vitamin-b12">Vitamin B12</a>, or cobalamin, is essential for making red blood cells, DNA (your genetic code), fatty acids located in <a href="https://en.wikipedia.org/wiki/Myelin">myelin</a> (which insulate nerves), and some neurotransmitters needed for brain function. </p>
<p>Vitamin B12 is stored in the liver, so a deficiency probably won’t happen in adults in the short term.</p>
<p><strong>Symptoms of B12 deficiency</strong></p>
<p>Symptoms of vitamin B12 <a href="https://www.healthline.com/health/vitamin-b12-level">deficiency</a> include tiredness, lethargy, low exercise tolerance, light-headedness, rapid heart rate or palpitations, bruising and bleeding easily, weight loss, impotence, bowel or bladder changes, a sore tongue, and bleeding gums. </p>
<p>Other <a href="https://www.nrv.gov.au/nutrients/vitamin-b12">symptoms related to the nervous system</a> include a loss of sensation in the hands or feet, problems related to movement, brain changes ranging from memory loss to mood changes or dementia, visual disturbances, and impaired bowel and bladder control. </p>
<p><strong>Testing for B12 deficiency</strong> </p>
<p>Your doctor may request a <a href="https://www.healthdirect.gov.au/vitamin-b12-test">blood test</a> to check your vitamin B12 status and determine whether indicators are in the <a href="https://www.labtestsonline.org.au/learning/test-index/vitamin-b12">healthy range</a>.</p>
<p><strong>Vegan food sources of B12</strong></p>
<p>Vitamin B12 is <a href="https://www.nrv.gov.au/nutrients/vitamin-b12">abundant in animal foods</a> including meat, milk and dairy products. </p>
<p>For vegans, plant sources of vitamin B12 include some algae and plants exposed to bacterial action or contaminated by soil or insects. While traces of vitamin B12 analogues can be found in some mushrooms, nori or fermented soy beans, more reliable sources include vitamin B12-supplemented soy or nut “milks”, or meat substitutes. Check the nutrition information panel on the label for the the B12 content. </p>
<p><a href="https://www.nrv.gov.au/nutrients/vitamin-b12">Crystalline vitamin B12</a> added to these products can boost the B12’s absorption rate to a level similar to that from animal products. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/271660/original/file-20190430-194609-1dzhtrz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/271660/original/file-20190430-194609-1dzhtrz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/271660/original/file-20190430-194609-1dzhtrz.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/271660/original/file-20190430-194609-1dzhtrz.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/271660/original/file-20190430-194609-1dzhtrz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/271660/original/file-20190430-194609-1dzhtrz.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/271660/original/file-20190430-194609-1dzhtrz.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Meat substitutes are often supplemented with B12.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/download/confirm/407288122?src=7DIfZxJLmk1QUWRMkz3hPA-1-14&size=huge_jpg">Stephanie Frey/Shutterstock</a></span>
</figcaption>
</figure>
<h2>2. Calcium</h2>
<p><a href="https://www.healthdirect.gov.au/calcium">Calcium</a> is needed to develop and maintain the skeleton bones, and is stored in the teeth and bones. It is also essential for heart, muscle and nerve function. </p>
<p><strong>Testing for calcium deficiency</strong> </p>
<p>Low calcium intakes are associated with <a href="https://www.osteoporosis.org.au/what-it">osteoporosis</a> or “brittle bones” and a higher risk of bone fractures. </p>
<p>A <a href="https://www.osteoporosis.org.au/diagnosis">bone scan is used</a> to measure bone density, with <a href="https://www.healthdirect.gov.au/osteoporosis-diagnosis">osteoporosis diagnosed</a> when bone density is low. </p>
<p>Both low calcium intakes and low vitamin D levels increase the risk of osteoporosis. Check your bone health using the <a href="https://www.knowyourbones.org.au/">Know Your Bones online quiz</a>. </p>
<p><strong>Vegan food sources of calcium</strong></p>
<p>Although the richest sources of calcium are milk and milk-based foods, vegans can get calcium from tofu or bean curd, some fortified soy or nut beverages, nuts, seeds, legumes, and breakfast cereals. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/271650/original/file-20190430-194603-e1fvju.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/271650/original/file-20190430-194603-e1fvju.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/271650/original/file-20190430-194603-e1fvju.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/271650/original/file-20190430-194603-e1fvju.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/271650/original/file-20190430-194603-e1fvju.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/271650/original/file-20190430-194603-e1fvju.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/271650/original/file-20190430-194603-e1fvju.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Nut and soy milks are a good source of calcium.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/soymilk-may-be-used-substitute-dairy-1294096993?src=Z28w0wPZMiLq6Rg4mQv3vA-1-9">Rodica Ciorba/Shutterstock</a></span>
</figcaption>
</figure>
<p>Calcium needs can be higher for vegans and vegetarians due to the relatively high <a href="https://en.wikipedia.org/wiki/Oxalic_acid">oxalic acid</a> content of foods such as spinach, rhubarb, beans, and the high <a href="https://en.wikipedia.org/wiki/Phytic_acid">phytic acid</a> content of seeds, nuts, grains, some raw beans, and soy products. These specific acids can lower the calcium absorption from these foods by 10-50%.</p>
<p>In a <a href="https://www.ncbi.nlm.nih.gov/pubmed/24667136">study of calcium intakes of 1,475 adults </a>, vegans were below national recommendations and had lower calcium intakes compared with vegetarians, semi-vegetarians, pesco-vegetarians, and omnivores.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/explainer-how-do-our-bones-get-calcium-and-why-do-they-need-it-75227">Explainer: how do our bones get calcium and why do they need it?</a>
</strong>
</em>
</p>
<hr>
<h2>3. Iodine</h2>
<p><a href="https://www.nrv.gov.au/nutrients/iodine">Iodine</a> is needed to make thyroxine, a thyroid hormone used in normal growth, regulation of metabolic rate, and development of the central nervous system. <a href="https://www.healthdirect.gov.au/iodine">Iodine</a> is concentrated in the thyroid gland.</p>
<p><strong>Symptoms of iodine deficiency</strong></p>
<p><a href="https://www.thyroidfoundation.org.au/Iodine-Deficiency">Iodine deficiency</a> can lead to the enlargement of the thyroid gland, a <a href="https://www.healthdirect.gov.au/goitre">goitre</a>, or hypothyroidism. </p>
<p><a href="https://www.thyroidfoundation.org.au/Iodine-Deficiency">Symptoms of hypothyroidism</a> include lethargy, tiredness, muscular weakness, feeling cold, difficulty concentrating, poor memory, weight gain, depression, facial puffiness, hair loss, dry skin, constipation, and slower heartbeat. </p>
<p>In women, iodine deficiency can increase risk of miscarriage and stillbirth, and congenital anomalies, including mental retardation and <a href="https://en.wikipedia.org/wiki/Congenital_iodine_deficiency_syndrome">cretinism</a>. </p>
<p><strong>Testing for iodine deficiency</strong> </p>
<p>Your iodine status can be assessed by a range of tests, including thyroid hormones in your blood, the size of your thyroid gland, or the presence of a goitre. Talk to your doctor about these tests. </p>
<p><strong>Vegan food sources of iodine</strong></p>
<p>The <a href="https://www.betterhealth.vic.gov.au/health/healthyliving/iodine">iodine content of food</a> depends on the iodine content of plants, which in turn depends on soil iodine content. When soil content is low, iodine may need to be supplemented. </p>
<p>Major sources of iodine are seafood, dairy products, and eggs. </p>
<p>For vegans, iodised salt, commercial bread made using iodised salt, fortified soy or nut milks (check the product label) and seaweed are important. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/271663/original/file-20190430-194609-1c673kh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/271663/original/file-20190430-194609-1c673kh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/271663/original/file-20190430-194609-1c673kh.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/271663/original/file-20190430-194609-1c673kh.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/271663/original/file-20190430-194609-1c673kh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/271663/original/file-20190430-194609-1c673kh.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/271663/original/file-20190430-194609-1c673kh.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Iodine is added to some salts.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/download/confirm/266034749?src=a3U1zoGU9rYfErdHsdPCoA-1-22&size=huge_jpg">IlzeTheBeast/Shutterstock</a></span>
</figcaption>
</figure>
<p>Substances called goitrogens, which are found in <a href="https://en.wikipedia.org/wiki/Brassica">brassica vegetables</a> – including cabbage, broccoli and Brussels sprouts, sweet potato and maize – can interfere with the production of thyroid hormones. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/lack-of-dietary-iodine-threatens-brain-development-in-children-14996">Lack of dietary iodine threatens brain development in children</a>
</strong>
</em>
</p>
<hr>
<h2>4. Iron</h2>
<p><a href="https://www.nrv.gov.au/nutrients/iron">Iron</a> is needed to make <a href="https://en.wikipedia.org/wiki/Hemoglobin">haemoglobin</a> in red blood cells, which carries oxygen around your body. </p>
<p>Iron is <a href="https://www.healthshare.com.au/factsheets/12147-iron-deficiency/">also needed for the production of energy</a> in your muscles, and for concentration and a healthy immune system. </p>
<p><strong>Symptoms and testing for iron deficiency and anaemia</strong></p>
<p>Not having enough iron leads to <a href="https://www.healthdirect.gov.au/iron-deficiency">iron deficiency</a>, and is associated with reduced work capacity, impaired brain function, lower immunity, and delayed development in infants. </p>
<p>The first stage of iron deficiency is referred to as <a href="https://www.betterhealth.vic.gov.au/health/ConditionsAndTreatments/iron-deficiency-adults">low iron stores</a> and your doctor may refer you for a <a href="https://www.healthdirect.gov.au/iron-studies">blood test</a> to check your iron status. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/ive-been-diagnosed-with-iron-deficiency-now-what-87670">I've been diagnosed with iron deficiency, now what?</a>
</strong>
</em>
</p>
<hr>
<p><strong>Vegan food sources of iron</strong></p>
<p>In Australia and New Zealand, the biggest contributors to iron intake are wholegrain cereals, meats, chicken, and fish. </p>
<p>The amount of iron absorbed from food depends on a person’s iron status (with those who are iron-deficient absorbing more), as well as the iron content of the entire meal, and whether iron is haem (from animal foods) or non-haem iron from plant sources such as grains and vegetables. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/271657/original/file-20190430-194633-1sxme7g.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/271657/original/file-20190430-194633-1sxme7g.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=401&fit=crop&dpr=1 600w, https://images.theconversation.com/files/271657/original/file-20190430-194633-1sxme7g.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=401&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/271657/original/file-20190430-194633-1sxme7g.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=401&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/271657/original/file-20190430-194633-1sxme7g.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/271657/original/file-20190430-194633-1sxme7g.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/271657/original/file-20190430-194633-1sxme7g.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Whole grains are rich in iron.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/download/confirm/1135582598?src=K3o6CoVyDdqRkgkQLKBNpw-1-0&size=huge_jpg">Photka/Shutterstock</a></span>
</figcaption>
</figure>
<p>Although iron from plant sources is less able to enter the body, you can boost your absorption by adding lemon or lime juice (citric acid) or other vitamin C-rich vegetables and fruits, which convert non-haem iron to a form than is better absorbed. </p>
<p>Take care with food components that inhibit absorption of both haem and non-haem iron, including calcium, zinc and phytates in legumes, rice and other grains, and <a href="https://foodwatch.com.au/blog/super-foods/item/top-100-polyphenols-what-are-they-and-why-are-they-important.html">polyphenols</a> and vegetable proteins that can inhibit absorption of non-haem iron. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/why-iron-is-such-an-important-part-of-your-diet-69974">Why iron is such an important part of your diet</a>
</strong>
</em>
</p>
<hr>
<p>Long-term vegans will also need to keep an eye on levels of <a href="https://www.betterhealth.vic.gov.au/health/healthyliving/vitamin-d">vitamin D</a>, <a href="https://www.heartfoundation.org.au/news/omega-3-fatty-acid-the-importance-of-fat-in-a-healthy-diet">omega-3 fat</a> and <a href="https://www.betterhealth.vic.gov.au/health/HealthyLiving/protein">protein</a>.</p>
<p>A good strategy is to check in with your GP periodically to review your health and well-being, and an <a href="https://daa.asn.au/find-an-apd/">accredited practising dietitian</a> can check whether you’re getting all the nutrients you need.</p><img src="https://counter.theconversation.com/content/107708/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Clare Collins is affiliated with the Priority Research Centre for Physical Activity and Nutrition, the University of Newcastle, NSW. She is an NHMRC Senior Research and Gladys M Brawn Research Fellow. She has received research grants from NHMRC, ARC, Hunter Medical Research Institute, Meat and Livestock Australia, Diabetes Australia, Heart Foundation, Bill and Melinda Gates Foundation, nib foundation, Rijk Zwaan Australia and Greater Charitable Foundation. She has consulted to SHINE Australia, Novo Nordisk, Quality Bakers, the Sax Institute and the ABC. She was a team member conducting systematic reviews to inform the Australian Dietary Guidelines update and 2017 evidence review on dietary patterns for the Heart Foundation.</span></em></p>Are you getting enough vitamin B12, calcium, iodine and iron? Here’s what can happen if you don’t get enough – and how to ensure you do.Clare Collins, Professor in Nutrition and Dietetics, University of NewcastleLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/804032017-07-04T01:35:51Z2017-07-04T01:35:51ZNo, nanoparticles in baby formula will not harm your baby<figure><img src="https://images.theconversation.com/files/176674/original/file-20170704-12293-t2rt7k.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">The health scare surrounding nanoparticles might lead to people abandoning formula unnecessarily, with serious impacts on babies' health.</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/download/confirm/392125570?size=medium_jpg">from www.shutterstock.com</a></span></figcaption></figure><p>If you watched Channel 7 news this week, you would have learnt about a <a href="http://www.smh.com.au/business/consumer-affairs/study-finds-potentially-toxic-nanoparticles-in-australian-baby-formula-20170622-gwwb2j.html">study</a> commissioned by <a href="http://www.foe.org/projects/food-and-technology/nanotechnology/baby-formula">Friends of the Earth</a> that found “potentially toxic” <a href="https://theconversation.com/nanoparticles-and-nanosafety-the-big-picture-22061">nanoparticles</a> in Australian baby formula.</p>
<p>The study’s spokesperson said calcium phosphate nanoparticles (nano-hydroxyapatite, also known as nano-hydroxylapatite) caused kidney and liver damage. That claim was, how shall I put it kindly, just a little <em>misleading</em>.</p>
<iframe src="https://www.facebook.com/plugins/video.php?href=https%3A%2F%2Fwww.facebook.com%2F7NewsAdelaide%2Fvideos%2F1606605372703445%2F&show_text=0&width=560" width="100%" height="450" style="border:none;overflow:hidden" scrolling="no" frameborder="0" allowtransparency="true" allowfullscreen="true"></iframe>
<p>I have the <a href="http://pubs.rsc.org/en/content/articlepdf/2012/nr/c2nr00044j">study</a> the spokesperson mentioned before me, which was conducted in rats, not humans.</p>
<p>The researchers injected calcium phosphate nanoparticles directly into rats’ body cavities (instead of oral administration as happens with baby formula) at concentrations around a million times higher than found in the baby formula.</p>
<p>Let me quote from the study’s findings:</p>
<blockquote>
<p>The normal levels of AST, ALT and A/G [liver enzymes indicating liver damage] in the n-HA [nano-hydroxyapatite] group suggested no inflammation and necrosis induced by accumulation of 100 mg of n-HA particles. In the liver function there was almost no damage. Moreover, no significant change on values of BUN and CR [urea and creatine] than the control, which also suggested n-HA has no effect on renal function.</p>
</blockquote>
<p>In other words, there were <em>no</em> ill effects on liver or kidney function, the direct opposite of what the media reports were claiming.</p>
<p>Even <em>if</em> you injected 100 milligrams of pure nano-hydroxyapatite directly into a newborn baby’s body (equivalent in baby terms to the dose given to the rats) there would be <em>no</em> significant effect on liver or kidney function.</p>
<p>The spokesperson’s misleading message caused unwarranted concern. On a now deleted <a href="https://www.facebook.com/Sunrise">Sunrise Facebook</a> post discussing this report, the commentors’ concern and fear was palpable. Causing unreasonable fear is irresponsible.</p>
<h2>Nanoparticles occur naturally</h2>
<p>Nanoparticles have become the latest bogeyman, despite nanoparticles occurring naturally. The <a href="http://www.smh.com.au/business/consumer-affairs/study-finds-potentially-toxic-nanoparticles-in-australian-baby-formula-20170622-gwwb2j.html">media report</a> that fuelled the controversy failed to put nanoparticles in their natural biological context, provide any significant support that particles detected in milk are engineered nanomaterials, nor provide evidence of harm for the levels found.</p>
<p>Infant formula is based on milk, which naturally contains calcium and phosphorus (as calcium phosphates). Milk is an important source of calcium, which forms the basis of bones and teeth. The calcium and phosphates are in a complex balance between soluble and protein-bound forms.</p>
<p>One of the forms of calcium phosphate in milk is <a href="https://hal.archives-ouvertes.fr/hal-00900570/document">hydroxyapatite</a> (also found in <a href="https://en.wikipedia.org/wiki/Hydroxylapatite">tooth enamel</a>). So it is unsurprising that hydroxyapatite is found in dried infant formula, which is mainly dried milk powder. </p>
<p>Nanometre-sized particles of calcium phosphate also <a href="https://www.ncbi.nlm.nih.gov/pubmed/6626580">form naturally</a> in drying milk.</p>
<h2>Other studies have found no effect</h2>
<p>Researchers have studied the safety of consuming hydroxyapatite nanoparticles before.</p>
<p>Animals who ate the nanoparticles (added to their food, as opposed to having them injected) showed <a href="http://www.sciencedirect.com/science/article/pii/S0928493116315703">no toxicity</a> at levels well above those present in milk (up to 100 milligrams per kilogram of body weight a day for a year). </p>
<p>Even if you inject them (into veins or into body cavities), you need levels well above those found in infant formulas to <a href="http://onlinelibrary.wiley.com/doi/10.1002/jat.3073/full">cause damage</a> (50 milligrams nano-hydroxyapatite per kilogram body weight in rats).</p>
<p>To give you an idea of how much higher this is with respect to infant formula, the highest levels of hydroxyapatite nanoparticles in any formula is 287 particles in 10 grams of formula.</p>
<p>Yes, that’s <em>particles</em> not milligrams, not micrograms but actual particles. We are talking nano- to femtograms here, amounts so small it is hard to visualise. These levels are a million times or more less than levels found to have produced no effects in animals (and even lower than levels that do cause damage).</p>
<p>Hydroxyapatite nanoparticles have been widely developed to aid bone repair, deliver drugs and have been extensively tested. All results suggest that even <a href="http://onlinelibrary.wiley.com/doi/10.1002/cphc.201200080/full">levels required to be drug delivery agents</a>, well above those found in baby formula, have no significant adverse effects.</p>
<h2>The body dissolves the nanoparticles anyway</h2>
<p>These nanoparticles will also not stay nanoparticles: they dissolve in the stomach fluids, allowing their calcium to be absorbed. </p>
<p>Newborns and very young babies’ stomach fluids are less acidic than older babies and young children (pH5), but <a href="http://www.sciencedirect.com/science/article/pii/S0003996997000447">still acidic enough to dissolve hydroxyapatite</a>. </p>
<p>And particles are more easily dissolved the smaller they are. So, nanoparticles are likely to be even more rapidly dissolved into their component calcium and phosphate ions than larger particles.</p>
<h2>What’s the take-home message?</h2>
<p>There are no significant public health implications for these small crystals of naturally occurring calcium phosphates in milk-based baby formula. </p>
<p>The way the Friends of the Earth study results have been presented, with misleading references to irrelevant studies, has caused unnecessary fear and concern, and may lead some to abandon formula unnecessarily, with negative impacts on baby health.</p><img src="https://counter.theconversation.com/content/80403/count.gif" alt="The Conversation" width="1" height="1" />
<h4 class="border">Disclosure</h4><p class="fine-print"><em><span>Ian Musgrave receives funding from the National Health and Medical Research Council to study adverse reaction to herbal medicines, and has previously been funded by the Australian Research Council to study potential natural product treatments for Alzheimer's disease. In previous years he has collaborated on work on the formation of amyloids from milk proteins. </span></em></p>A widely publicised study that cast doubt on the safety of milk formula was misleading, based on dubiously reported studies and may have serious consequences.Ian Musgrave, Senior lecturer in Pharmacology, University of AdelaideLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/752272017-03-29T19:20:10Z2017-03-29T19:20:10ZExplainer: how do our bones get calcium and why do they need it?<figure><img src="https://images.theconversation.com/files/163024/original/image-20170329-1642-4pcnp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Dietary calcium is necessary to ensure our bones hold on to all the calcium they need to stay strong. </span> <span class="attribution"><a class="source" href="https://www.flickr.com/photos/goincase/5220924023/">Incase/Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span></figcaption></figure><p>Celebrity chef Pete Evans <a href="http://www.smh.com.au/entertainment/doctor-criticises-chef-pete-evans-for-giving-potentially-deadly-diet-advice-20160829-gr3ydb.html">was reported</a> recently <a href="https://au.news.yahoo.com/sunday-night/features/a/34792906/my-kitchen-rules-judge-pete-evans-launches-attack-on-media-ama-says-he-shouldnt-dabble-in-medicine/#page1">as saying</a> “calcium from dairy can remove the calcium from your bones”, and can worsen osteoporosis. The <a href="https://www.theguardian.com/australia-news/2017/mar/27/ama-accuses-pete-evans-of-endangering-lives-with-unscientific-health-advice">Australian Medical Association has expressed concerns</a> that Evans is disseminating misinformation, and in so doing may endanger lives. </p>
<p>But this brings us to the question of how our bones get calcium, and why they lose it.</p>
<p>Calcium provides mechanical rigidity to bones and teeth, and 99% of the body’s 1kg of calcium <a href="https://www.ncbi.nlm.nih.gov/pubmed/9263260">is in the skeleton</a>. Calcium is also essential for many other processes, including the function of muscles and nerves.</p>
<p>During periods of fasting, or if dietary calcium is in short supply, calcium is released from bone to maintain the critical level in the bloodstream needed for nerve and muscle function. If a shortage of calcium intake continues over time, bones are likely to become thinner and more porous, and, ultimately, more likely to break or “fracture”.</p>
<p>The calcium in the skeleton of a newborn baby has come from the mother and then from breast milk. But as the baby grows, more calcium will be needed. This can only come from dietary sources. Calcium is absorbed through the gut with the help of Vitamin D.</p>
<p>It then travels in the blood, with some eventually stored with another element, phosphorus, in bone crystals, which increase the strength of bone. Calcium remains there until it is required - for example, when the levels of calcium in the blood fall - when it is released. If the stores of calcium are released repeatedly, the bone becomes weak and thin.</p>
<p>So the level of calcium in the blood each day reflects a balance between what is absorbed from the diet, released from bone and lost through the gut, kidneys and skin. </p>
<p>The loss of calcium through these organs is a normal part of the body’s metabolism (for example, calcium may be exchanged for other elements such as sodium, a component of salt). Absorbing calcium from the diet offsets these losses and allows the body to maintain overall calcium balance between what comes in and what goes out.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/163025/original/image-20170329-1681-ixmwt5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/163025/original/image-20170329-1681-ixmwt5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/163025/original/image-20170329-1681-ixmwt5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/163025/original/image-20170329-1681-ixmwt5.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/163025/original/image-20170329-1681-ixmwt5.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/163025/original/image-20170329-1681-ixmwt5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/163025/original/image-20170329-1681-ixmwt5.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/163025/original/image-20170329-1681-ixmwt5.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The calcium in our bones initially came from our mother, and then from breast milk.</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/mrdelayer/249958581/">Matt Galisa/Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<p>Exactly how much calcium is needed varies according to circumstance. For example, more calcium is needed at times of high skeletal activity, such as growth. Other examples of higher demand include pregnancy, breast feeding and menopause.</p>
<p>The recommended daily intake of a nutrient is that needed to meet the needs of 98% of the population. The current recommended daily intake for calcium in Australia and New Zealand for women aged 19 to 50 years and men aged 19 to 70 years <a href="https://www.nrv.gov.au/nutrients/calcium">is 1000mg/day</a>.</p>
<p>The recommendations are slightly higher in children and adolescents (1000-1300mg/day) and in pregnant or lactating teenagers (1300mg/day).</p>
<p>On average, only about one third of calcium ingested is absorbed through the gut wall, though this can vary depending on other factors. These include how much vitamin D we have in our bodies, which actively increases calcium absorption.</p>
<p>Calcium absorption declines with age. So older people need calcium levels in their diet to maintain calcium balance. Calcium absorption also declines with menopause.</p>
<p>Calcium is absorbed both across and between the gut wall cells. The gut cannot inherently differentiate between calcium obtained from one type of food or another.</p>
<h2>Best sources of calcium</h2>
<p>Dairy foods are the <a href="https://www.nhmrc.gov.au/_files_nhmrc/publications/attachments/n31.pdf">richest source of calcium</a> in the diet. Although butter and cream do not contribute calcium in significant amounts, other dairy products such as milk, cheese and yoghurt (both full fat and low fat) do. Calcium is in the “watery” part of milk, so using low fat dairy products does not compromise calcium intake.</p>
<p>The 2011/2012 Australian Health survey reported <a href="http://www.abs.gov.au/AUSSTATS/abs@.nsf/DetailsPage/4364.0.55.0072011-12?OpenDocument">almost half of the calcium intake</a> among Australian adults was obtained from dairy products, particularly in older Australians.</p>
<p>Dairy foods are also excellent sources of protein, which can be particularly important in assisting frail elderly people maintain muscle tone, and thus help reduce their risk of falls.</p>
<p>Although the richest and best absorbed source, dairy foods are not the only source of dietary calcium. Bony fish (such as tinned salmon or sardines), legumes and some nuts such as almonds, and fortified soy milk and breakfast cereals can also provide calcium in lesser amounts. </p>
<p>But absorption of calcium from non-dairy foods may be poorer than absorption from dairy. Calcium is less well absorbed from foods high in a type of acid called phytates (such as seeds, nuts, grains) or substances called oxalates which are found in many plants (such as spinach and beans). This is because they bind to the calcium and make it harder to absorb.</p>
<p>Calcium supplements can also provide dietary calcium. Absorption from calcium supplements depends on their dose (lower doses, usually below 500mg, are absorbed more effectively) and timing (more is absorbed when taken with food). If taken correctly, absorption may be comparable to that from dairy, but higher doses taken without food are unlikely to absorb well.</p>
<h2>Why dietary calcium is important</h2>
<p>Our bones reach their highest mass during our 20s. Our bones later lose density during normal “ageing”, increasing the risk of fracture. It’s estimated that a fracture occurs <a href="http://www.osteoporosis.org.au/sites/default/files/files/Burden%20of%20Disease%20Analysis%202012-2022.pdf">every 3.6 minutes in Australian adults</a> aged 50 years and over.</p>
<p>Ensuring adequate dietary calcium intake, maintaining a healthy vitamin D level, not smoking, and participating regularly in weight-bearing and resistance exercise are all important lifestyle measures that can help optimise bone health. </p>
<p>Early research showed an adequate supply of dietary calcium <a href="http://www.sciencedirect.com/science/article/pii/S002203029477291X?via%3Dihub">reduces the release of calcium from bone</a> and a <a href="https://www.ncbi.nlm.nih.gov/pubmed/420146">higher consumption of dairy products</a> is associated with lower risk of fractures.</p>
<p>Inadequate calcium intake is detrimental to bone health. But once adequate calcium intake is achieved, little additional bone benefits are seen, and supplementing calcium intake above the recommended daily intake <a href="https://www.mja.com.au/system/files/issues/190_06_160309/san10083_fm.pdf">doesn’t have much effect</a> on fracture rates.</p><img src="https://counter.theconversation.com/content/75227/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Emma Duncan receives research funding from the National Health and Medical Research Council Australia. She is the president of the Australian and New Zealand Bone and Mineral Society (2015-17) and is affiliated with the American Society of Bone and Mineral Research and the Endocrine Society of Australia.</span></em></p><p class="fine-print"><em><span>Kerrie Sanders worked on a study funded by MG Nutritionals in 2006. </span></em></p><p class="fine-print"><em><span>Peter Robert Ebeling AO receives funding from National Health and Medical Research Council (NHMRC). He is affiliated with NHMRC, Osteoporosis Australia, International Osteoporosis Foundation and American Society for Bone and Mineral Research. </span></em></p><p class="fine-print"><em><span>Warrick Inder is affiliated with The Endocrine Society of Australia. </span></em></p>If dietary calcium is in short supply, calcium is released from bone to maintain the critical level in the bloodstream needed for nerve and muscle function.Emma Duncan, Professor of Medicine, Faculty of Medicine, The University of QueenslandKerrie Sanders, Professor -Musculoskeletal Science, Nutrition and Health economics, IHA, Australian Catholic UniversityPeter Robert Ebeling, Head, Department of Medicine, School of Clinical Sciences; Professor of Medicine, Monash UniversityWarrick Inder, Associate Professor, Diabetes and Endocrinology, The University of QueenslandLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/709702017-01-09T12:12:27Z2017-01-09T12:12:27ZWhat happens to your gut if you eat the $2,000 New York pizza topped with gold?<figure><img src="https://images.theconversation.com/files/152114/original/image-20170109-23468-xjv5yg.png?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Cock and bullion: the $2,000 pizza. </span> <span class="attribution"><span class="source">Industry Kitchen</span></span></figcaption></figure><p>A restaurant in the New York financial district <a href="http://www.maxim.com/entertainment/2000-dollar-gold-pizza-2017-1">is offering customers a pizza</a> priced at US$2,000 (£1,623). It is topped with caviar, stilton cheese and gold leaf, with each bite costing around US$50. </p>
<p>New York is usually the kind of place that sets trends, but pizzerias elsewhere have actually been making pizzas sparkle for a while. A takeaway pizza chain in London <a href="http://www.mirror.co.uk/news/weird-news/worlds-most-expensive-pizza-500-7395670">started offering</a> £500 pizzas a year ago, this time with added lobster, caviar and truffle oil; while a Glasgow restaurant <a href="http://www.dailyrecord.co.uk/business/business-news/savour-pleasures-classic-italian-food-3081571">attracted attention</a> by selling a gold leaf pizza on eBay. </p>
<p>Gold on food goes back a good deal further than that, however. The renowned Italian chef, Gualtiero Marchesi, <a href="https://www.finedininglovers.com/blog/food-drinks/marchesi-milanese-gold-risotto/">has been</a> topping his signature dish, risotto alla milanese, with a single leaf of gold for decades. And that too is recent when you reflect that the kitchens of the wealthy were <a href="https://books.google.co.uk/books?id=HectxYEZg0oC&pg=PA110&lpg=PA110&dq=%22gold+leaf%22+food+medieval&source=bl&ots=mB3ymFLK31&sig=YBWFZOikAbP__r2nmgGwbsWTKSc&hl=en&sa=X&ved=0ahUKEwj4lJ-i863RAhXCORoKHbaRDggQ6AEIUjAO#v=onepage&q=%22gold%20leaf%22%20food%20medieval&f=false">sprinkling</a> the precious metal on feast cuisine <a href="https://cornucaupia.com/deiaurum/wiki-gold-and-silver-leaf-edible-html/">during</a> medieval times. </p>
<p>There is a medieval liqueur still consumed today with gold flakes in it known as <a href="http://www.local-life.com/gdansk/articles/goldwasser">Goldwasser</a>. Gold leaf is <a href="http://www.ediblegold.co.uk">also used</a> on chocolates and even has an E number (<a href="http://www.ukfoodguide.net/e175.htm">E175</a>). Whatever else has changed over the years, swallowing gold has always been considered the highest form of decadence. But what happens when we put gold into the body? And are there any other metals we’d be better off shaving on to pizzas instead?</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/152017/original/image-20170106-18662-hzyla2.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/152017/original/image-20170106-18662-hzyla2.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/152017/original/image-20170106-18662-hzyla2.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=460&fit=crop&dpr=1 600w, https://images.theconversation.com/files/152017/original/image-20170106-18662-hzyla2.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=460&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/152017/original/image-20170106-18662-hzyla2.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=460&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/152017/original/image-20170106-18662-hzyla2.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=578&fit=crop&dpr=1 754w, https://images.theconversation.com/files/152017/original/image-20170106-18662-hzyla2.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=578&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/152017/original/image-20170106-18662-hzyla2.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=578&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Better than chicken nuggets.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/pic-340054991/stock-photo-superhero-pizza-man.html?src=ZSpgSF_i8bp_bygQHn3pYw-1-49">Luis Molinero</a></span>
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</figure>
<h2>Eat your carats</h2>
<p>Gold is an inert metal and is therefore not degraded by the acid in our stomachs. It will travel the length of the intestinal system unchanged, passing out in your poo. Depending on the sewage treatment system, it will eventually be returned to the land or washed out to sea ready to be recycled again. It casts panning for gold in an entirely new light. </p>
<p>Other metals are generally not used for ostentatious displays of edible wealth, but one exception is silver. Silver can be beaten into a leaf similar to gold and is also approved for use as an additive (<a href="http://www.ukfoodguide.net/e174.htm">E174</a>) – so long as it is pure and in its non-ionic form, which is the one that can’t be absorbed by the body. </p>
<p>Even then it is easier to add other metals to silver than gold, so there is still the risk it can be contaminated with the likes of aluminium. This can reduce the body’s ability to absorb essential minerals such as zinc, calcium and iron (aluminium is not essential). This will cause deficiency symptoms as diverse as soft bones (calcium), tiredness (iron) and lack of smell (zinc). </p>
<p>You might think these minerals might therefore be just the thing for a pizza, so long as they are in the ionic form that the body needs. We tend not to notice them in our diet but they are ubiquitous in grains, fruit and vegetables as they are essential for plant growth, too. Meat and dairy products are particularly rich sources and we have a very efficient system of absorbing the minerals they contain. </p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/152016/original/image-20170106-18641-1v1lceu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/152016/original/image-20170106-18641-1v1lceu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/152016/original/image-20170106-18641-1v1lceu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=626&fit=crop&dpr=1 600w, https://images.theconversation.com/files/152016/original/image-20170106-18641-1v1lceu.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=626&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/152016/original/image-20170106-18641-1v1lceu.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=626&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/152016/original/image-20170106-18641-1v1lceu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=787&fit=crop&dpr=1 754w, https://images.theconversation.com/files/152016/original/image-20170106-18641-1v1lceu.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=787&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/152016/original/image-20170106-18641-1v1lceu.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=787&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<span class="caption">Chewy sandwich filling.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/pic-466277147/stock-photo-iron-nails-on-a-wooden-yellow-backgroundselective-focusvintage-tone.html?src=5bMDe08D-GqUYB0m8CN9YA-1-44">mansong suttakam</a></span>
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</figure>
<p>One reason we don’t see minerals grated on our foods, of course, is that they don’t give the same bling value. But they will also react with the acid in our stomachs and get absorbed, since they are not inert. Excessive amounts of minerals in the body can be toxic, since they get laid down in soft tissues such as the brain and kidneys. This causes severe pain and eventually death. </p>
<p>In normal circumstances the body avoids such horrors by only absorbing a percentage of the minerals in the foods we eat. But if you flood the system with a mineral by taking large quantities, it can cause an excessive intake. As well as the toxicity risk, excessive intake of one essential mineral can make the body struggle to properly absorb other essential minerals – the same risk as when you ingest non-essential minerals like aluminium. </p>
<p>The bottom line is about balance, as with most of nutrition. Since there’s plenty of these minerals in the foods we eat, there’s absolutely no need and much potential harm to be had from adding any extra to our meals – or from taking supplements we don’t need. </p>
<p>Better to stick to gold, which does nothing good or bad for health except perhaps a feeling of satisfaction – or regret if you see it twinkling as it disappears down the drain. And if you’ve more money than sense and you’re still hungry for more after that gold pizza, you could always ask your willing chef to throw in a few diamonds next time. They’re inert, too, albeit a little crunchy.</p><img src="https://counter.theconversation.com/content/70970/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Marie-Ann Ha does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>On sale in New York for US$2,000. Don’t all rush at once.Marie-Ann Ha, Senior Lecturer in Nutrition, Anglia Ruskin UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/598852016-11-14T04:36:03Z2016-11-14T04:36:03ZHealth Check: is cheese good for you?<figure><img src="https://images.theconversation.com/files/145005/original/image-20161108-29124-8ae9vg.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">We need protein and calcium, but shouldn't have too much fat and salt. So what's the verdict on cheese?</span> <span class="attribution"><span class="source">from www.shutterstock.com.au</span></span></figcaption></figure><p>It’s no wonder people are confused about whether it’s good to eat cheese, when even food experts are divided. Some argue that we’re not eating enough of this important source of protein and calcium, while others say the high levels of salt and saturated fat mean we should be eating less.</p>
<p>Whatever your position, it’s becoming increasingly hard to avoid cheese. Whether its grilled halloumi with poached eggs for breakfast, pumpkin and feta salad for lunch, or pepperoni pizza for dinner, cheese is a key ingredient in many regular meals. It’s a popular snack food, with many health professionals promoting crackers and cheese as a high-protein snack. A cheese platter is also the favourite way to kick off afternoon drinks or a barbeque.</p>
<p>So just how much cheese are Australians eating, and is it good for us?</p>
<p>The <a href="https://www.eatforhealth.gov.au/guidelines/australian-dietary-guidelines-1-5">Australian Dietary Guidelines</a> recommend that adults eat about 2.5 serves of dairy (including milk, yoghurt and cheese) a day. They also say this should preferably be low-fat to ensure that nutrient needs are met without exceeding energy requirements.</p>
<p><a href="http://www.dairyinfo.gc.ca/index_e.php?s1=dff-fcil&s2=cons&s3=consglo&s4=tc-ft">Available sales data for cheese</a> suggest that Australians are eating 13.6kg of cheese per person per year, which works out at 37g per person per day, or just less than one Australian portion (Australian portion sizes are 25% bigger than European Union ones, at 40g compared with 30g).</p>
<h2>Fat</h2>
<p>It seems that the advice to limit full-fat cheeses to two or three serves per week is being ignored. Low-fat products <a href="http://www.abs.gov.au/ausstats/abs@.nsf/Lookup/4364.0.55.012main+features12011-12">only made up 29%</a> of dairy products consumed in the last dietary survey while cheese accounted for 99% of the high-fat dairy products consumed. </p>
<p>Full-fat cheese products contain high levels of saturated fat, which can <a href="https://www.heartfoundation.org.au/healthy-eating/food-and-nutrition/fats-and-cholesterol/saturated-and-trans-fat">increase the risk of heart disease</a>. A 40g portion of cheese <a href="http://www.legendairy.com.au/%7E/media/Legendairy/Documents/Health/Fact%20sheets/2012%20Proximate%20Composition%20Booklet.ashx">can contain between</a> 2.24g (reduced-fat ricotta) and 9.5g (Danish creamy cheese Havarti) of saturated fat.</p>
<p>This is 11% and 40%, respectively, of the amount used as the <a href="http://www.mydailyintake.net/daily-intake-levels">reference guide for daily intake labelling</a>. So even though actual recommendations depend on individual energy requirements, it is still clear that we need to limit our consumption of full-fat cheese to avoid excessive amounts of saturated fat.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/145006/original/image-20161108-29136-224lor.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/145006/original/image-20161108-29136-224lor.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/145006/original/image-20161108-29136-224lor.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=399&fit=crop&dpr=1 600w, https://images.theconversation.com/files/145006/original/image-20161108-29136-224lor.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=399&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/145006/original/image-20161108-29136-224lor.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=399&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/145006/original/image-20161108-29136-224lor.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=501&fit=crop&dpr=1 754w, https://images.theconversation.com/files/145006/original/image-20161108-29136-224lor.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=501&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/145006/original/image-20161108-29136-224lor.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=501&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Saturated fats are bad for heart health.</span>
<span class="attribution"><span class="source">from www.shutterstock.com</span></span>
</figcaption>
</figure>
<h2>Salt</h2>
<p>The levels of sodium in cheese are also something to watch out for as too much salt increases blood pressure, which increases the risk of heart disease and stroke.</p>
<p>Sodium levels in one 40g portion of cheese range from 74mg (<a href="http://www.who.int/nutrition/publications/guidelines/sodium_intake/en/">4% of the World Health Organisation’s (WHO)</a> recommended daily amount) in reduced-fat ricotta, to a scary 1,160mg (<a href="http://www.legendairy.com.au/%7E/media/Legendairy/Documents/Health/Fact%20sheets/2012%20Proximate%20Composition%20Booklet.ashx">58% of the WHO’s</a> recommended daily amount) in halloumi.</p>
<p>Interestingly, processed cheddar contains twice as much sodium as unprocessed cheddar, at 532mg per portion (26% of WHO recommended amount), so it would seem better to opt for the unprocessed version on that basis (although this may have higher levels of saturated fat and less calcium).</p>
<h2>Processed cheeses</h2>
<p>The <a href="https://www.foodstandards.gov.au/code/code-revision/Documents/35%20-%20Standard%202.5.4%20.pdf">definition of a processed cheese</a> is a product manufactured from cheese and products obtained from milk, which is heated and melted, with or without added emulsifying salts, to form a homogeneous mass. </p>
<p>Such products can be produced more cheaply, last longer and are more convenient to use and so are a popular product for kids’ school lunchboxes. Current concerns over increasing childhood obesity in Australia means its important to keep an eye on fat and energy contents of children’s foods.</p>
<p>Kraft singles and Bega Stringers both contain a little less energy, substantially less saturated fat, and about the same amount of sodium and calcium per portion as regular cheddar cheese. Meanwhile, Philadelphia cream cheese contains even less energy and much less sodium but is higher in saturated fat.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/145007/original/image-20161108-29136-1hut6qb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/145007/original/image-20161108-29136-1hut6qb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=389&fit=crop&dpr=1 600w, https://images.theconversation.com/files/145007/original/image-20161108-29136-1hut6qb.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=389&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/145007/original/image-20161108-29136-1hut6qb.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=389&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/145007/original/image-20161108-29136-1hut6qb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=489&fit=crop&dpr=1 754w, https://images.theconversation.com/files/145007/original/image-20161108-29136-1hut6qb.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=489&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/145007/original/image-20161108-29136-1hut6qb.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=489&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Are we getting any nutrition from highly processed cheeses?</span>
<span class="attribution"><span class="source">from www.shutterstock.com</span></span>
</figcaption>
</figure>
<h2>Health benefits?</h2>
<p>A <a href="https://www.ncbi.nlm.nih.gov/pubmed/27517544">recent meta-analysis</a> of 15 studies, that suggested moderate cheese consumption (up to 40g per day) was associated with reduced heart disease risk, didn’t differentiate between low and full fat cheeses. </p>
<p>The authors (two of whom incidentally work for a leading dairy company in Asia) suggested the calcium, protein, vitamins or minerals (not specified) in cheese might explain the apparent protective health benefits.</p>
<p>Cheese is a <a href="https://www.nrv.gov.au/nutrients/calcium">good source of calcium</a> and we need calcium for bones and teeth as well as regulating muscle and heart functions. </p>
<p>The recommendations are for most adults and children aged nine and above to eat 1,000-1,300mg of calcium a day. A 40g serving of cheddar cheese contains around 320mg. So you would need to eat at least three portions if you were to get your calcium requirements just from cheese.</p>
<h2>So what’s the verdict?</h2>
<p>For maximum health outcomes I’d stick to the advice to eat two to three serves of dairy (mainly low fat) per day. This may include one serve of low-fat cheese, with maybe one serve each of low-fat milk and yoghurt to ensure you get enough calcium. I’d also stick with the recommendations to limit full-fat cheeses to two to three serves per week. </p>
<ul>
<li><p>Enjoy sparingly (two to three times a week): full-fat cheeses, hard cheeses, feta, halloumi, blue cheese. </p></li>
<li><p>Eat moderate amounts (one portion a day): low-fat cheeses, cottage cheese, reduced fat ricotta, reduced fat mozarella.</p></li>
</ul><img src="https://counter.theconversation.com/content/59885/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Jacqui Webster is supported by a National Health and Medical Research Council Career Development Fellowship and a National Heart Foundation Future Leaders Award and receives additional project funding from The National Health and Medical Research Council, The World Health Organization and The Victorian Health Promotion Foundation. </span></em></p>It’s no wonder people are confused about whether it’s good to eat cheese, when even food experts are divided.Jacqui Webster, Senior Research Fellow, Food Policy. Director of World Health Organization Collaborating Centre on Population Salt Reduction, George Institute for Global HealthLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/592462016-05-17T10:04:47Z2016-05-17T10:04:47ZNanoparticles in baby formula: should parents be worried?<figure><img src="https://images.theconversation.com/files/122746/original/image-20160516-15906-1ymu3xg.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">What's in the bottle is good for me, right?</span> <span class="attribution"><a class="source" href="https://www.flickr.com/photos/21524179@N08/3669555322">nerissa's ring</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span></figcaption></figure><p>There’s a lot of stuff you’d expect to find in baby formula: proteins, carbs, vitamins, essential minerals. But parents probably wouldn’t anticipate finding extremely small, needle-like particles. Yet this is exactly what a team of scientists here at Arizona State University <a href="http://www.foe.org/projects/food-and-technology/nanotechnology/baby-formula">recently discovered</a>.</p>
<p>The research, commissioned and published by Friends of the Earth (<a href="http://www.foe.org/">FoE</a>) – an environmental advocacy group – analyzed six commonly available off-the-shelf baby formulas (liquid and powder) and found nanometer-scale needle-like particles in three of them. The particles were made of hydroxyapatite – a poorly soluble calcium-rich mineral. Manufacturers use it to regulate acidity in some foods, and it’s also available as a dietary supplement.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/122339/original/image-20160512-5088-12g9emr.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/122339/original/image-20160512-5088-12g9emr.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/122339/original/image-20160512-5088-12g9emr.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=596&fit=crop&dpr=1 600w, https://images.theconversation.com/files/122339/original/image-20160512-5088-12g9emr.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=596&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/122339/original/image-20160512-5088-12g9emr.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=596&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/122339/original/image-20160512-5088-12g9emr.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=748&fit=crop&dpr=1 754w, https://images.theconversation.com/files/122339/original/image-20160512-5088-12g9emr.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=748&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/122339/original/image-20160512-5088-12g9emr.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=748&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Needle-like particles of hydroxyapatite found in infant formula by ASU researchers.</span>
<span class="attribution"><span class="source">Westerhoff and Schoepf/ASU</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>Looking at these particles at super-high magnification, it’s hard not to feel a little anxious about feeding them to a baby. They appear sharp and dangerous – not the sort of thing that has any place around infants. And they are “nanoparticles” – a family of ultra-small particles that have been <a href="http://dx.doi.org/10.1038/444267a">raising safety concerns within the scientific community</a> and elsewhere for some years.</p>
<p>For all these reasons, questions like “should infants be ingesting them?” make a lot of sense. However, as is so often the case, the answers are not quite so straightforward.</p>
<h2>What are these tiny needles?</h2>
<p>Calcium is an essential part of a growing infant’s diet, and is a <a href="http://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfcfr/CFRSearch.cfm?fr=107.100">legally required component</a> in formula. But not necessarily in the form of hydroxyapatite nanoparticles.</p>
<p>Hydroxyapatite is a tough, durable mineral. It’s naturally made in our bodies as an essential part of bones and teeth – <a href="https://en.wikipedia.org/wiki/Hydroxylapatite">it’s what makes them so strong</a>. So it’s tempting to assume the substance is safe to eat. But just because our bones and teeth are made of the mineral doesn’t automatically make it safe to ingest outright.</p>
<p>The issue here is what the hydroxyapatite in formula might do before it’s digested, dissolved and reconstituted inside babies’ bodies. The size and shape of the particles ingested has a lot to do with how they behave within a living system.</p>
<p>Size and shape can make a difference between <a href="http://www.webmd.com/news/breaking-news/food-additives/20150723/nanoparticles-food-additives">safe and unsafe</a> when it comes to particles in our food. Small particles aren’t necessarily bad. But they can potentially get to parts of our body that larger ones can’t reach. Think through the gut wall, into the bloodstream, and into organs and cells. Ingested nanoscale particles may be able to <a href="http://dx.doi.org/10.1080/02652030701744538">interfere with cells</a> – even beneficial gut microbes – in ways that larger particles don’t.</p>
<p>These possibilities don’t necessarily make nanoparticles harmful. Our bodies are pretty well adapted to handling naturally occurring nanoscale particles – you probably ate some last time you had burnt toast (carbon nanoparticles), or poorly washed vegetables (clay nanoparticles from the soil). And of course, how much of a material we’re exposed to is at least as important as how potentially hazardous it is. </p>
<p>Yet there’s a lot we still don’t know about the safety of intentionally engineered nanoparticles in food. Toxicologists have <a href="http://dx.doi.org/10.1289%2Fehp.7339">started paying close attention to such particles</a>, just in case their tiny size makes them more harmful than otherwise expected.</p>
<p>So where does this leave us with nanoscale hydroxyapatite needles in infant formula?</p>
<h2>What do regulators know about nano-safety?</h2>
<p>Putting particle size to one side for a moment, hydroxyapatite is classified by the US Food and Drug Administration (FDA) as “Generally Regarded As Safe.” That means it considers the material safe for use in food products – at least in a non-nano form. However, <a href="http://www.fda.gov/Food/GuidanceRegulation/GuidanceDocumentsRegulatoryInformation/ucm300661.htm">the agency has raised concerns</a> that nanoscale versions of food ingredients may not be as safe as their larger counterparts. </p>
<p>Some manufacturers may be interested in the potential benefits of “nanosizing” – such as increasing the uptake of vitamins and minerals, or altering the physical, textural and sensory properties of foods. But because decreasing particle size may also affect product safety, the FDA indicates that intentionally nanosizing already regulated food ingredients could require regulatory reevaluation.</p>
<p>In other words, even though non-nanoscale hydroxyapatite is “Generally Regarded As Safe,” according to the FDA, the safety of any nanoscale form of the substance would need to be reevaluated before being added to food products.</p>
<p>Despite this size-safety relationship, the FDA confirmed to me that the agency is unaware of <em>any</em> food substance intentionally engineered at the nanoscale that has enough generally available safety data to determine it should be “Generally Regarded As Safe.”</p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/122057/original/image-20160511-18165-nr0qig.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/122057/original/image-20160511-18165-nr0qig.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/122057/original/image-20160511-18165-nr0qig.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=597&fit=crop&dpr=1 600w, https://images.theconversation.com/files/122057/original/image-20160511-18165-nr0qig.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=597&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/122057/original/image-20160511-18165-nr0qig.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=597&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/122057/original/image-20160511-18165-nr0qig.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=751&fit=crop&dpr=1 754w, https://images.theconversation.com/files/122057/original/image-20160511-18165-nr0qig.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=751&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/122057/original/image-20160511-18165-nr0qig.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=751&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Hydroxyapatite nanoparticles may have different health effects from larger versions of the mineral.</span>
<span class="attribution"><span class="source">Westerhoff and Schoepf/ASU</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>Casting further uncertainty on the use of nanoscale hydroxyapatite in food, a 2015 report from the European Scientific Committee on Consumer Safety (SCCS) suggests there <a href="http://ec.europa.eu/health/scientific_committees/consumer_safety/docs/sccs_o_191.pdf">may be some cause for concern</a> when it comes to this particular nanomaterial. </p>
<p>Prompted by the use of nanoscale hydroxyapatite in dental products to strengthen teeth (which they consider “cosmetic products”), the SCCS reviewed published research on the material’s potential to cause harm. Their conclusion?</p>
<blockquote>
<p>The available information indicates that nano-hydroxyapatite in needle-shaped form is of concern in relation to potential toxicity. Therefore, needle-shaped nano-hydroxyapatite should not be used in cosmetic products.</p>
</blockquote>
<p>This recommendation was based on a handful of studies, none of which involved exposing people to the substance. Researchers injected hydroxyapatite needles directly into the bloodstream of rats. Others exposed cells outside the body to the material and observed the effects. In each case, there were tantalizing hints that the small particles interfered in some way with normal biological functions. But the results were insufficient to indicate whether the effects were meaningful in people.</p>
<p>Importantly, these studies didn’t consider what happens when particles like this end up in the digestive system, including the stomach.</p>
<h2>So what happens when a baby eats them?</h2>
<p>The good news is that, according to preliminary studies from ASU researchers, hydroxyapatite needles don’t last long in the digestive system.</p>
<p>This research is still being reviewed for publication. But early indications are that as soon as the needle-like nanoparticles hit the highly acidic fluid in the stomach, they begin to dissolve. So fast in fact, that by the time they leave the stomach – an exceedingly hostile environment – they are no longer the nanoparticles they started out as.</p>
<p>These findings make sense since we know hydroxyapatite dissolves in acids, and small particles typically dissolve faster than larger ones. So maybe nanoscale hydroxyapatite needles in food are safer than they sound.</p>
<p>This doesn’t mean that the nano-needles are completely off the hook, as some of them may get past the stomach intact and reach more vulnerable parts of the gut. But the findings do suggest these ultra-small needle-like particles could be an effective source of dietary calcium – possibly more so than larger or less needle-like particles that may not dissolve as quickly.</p>
<p>Intriguingly, recent research has indicated that calcium phosphate nanoparticles form naturally in our stomachs and go on to be <a href="http://doi.org/10.1038/nnano.2015.19">an important part of our immune system</a>. It’s possible that rapidly dissolving hydroxyapatite nano-needles are actually a boon, providing raw material for these natural and essential nanoparticles.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/122747/original/image-20160516-15926-1q2xeo4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/122747/original/image-20160516-15926-1q2xeo4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/122747/original/image-20160516-15926-1q2xeo4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=374&fit=crop&dpr=1 600w, https://images.theconversation.com/files/122747/original/image-20160516-15926-1q2xeo4.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=374&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/122747/original/image-20160516-15926-1q2xeo4.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=374&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/122747/original/image-20160516-15926-1q2xeo4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=470&fit=crop&dpr=1 754w, https://images.theconversation.com/files/122747/original/image-20160516-15926-1q2xeo4.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=470&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/122747/original/image-20160516-15926-1q2xeo4.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=470&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The formula’s safe, but begs other questions.</span>
<span class="attribution"><span class="source">Andrew Maynard</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<h2>Tempest in a baby bottle</h2>
<p>And yet, even if these needle-like hydroxyapatite nanoparticles in infant formula are ultimately a good thing, the FoE report raises a number of unresolved questions. Did the manufacturers knowingly add the nanoparticles to their products? How are they and the FDA ensuring the products’ safety? Do consumers have a right to know when they’re feeding their babies nanoparticles?</p>
<p>Whether the manufacturers knowingly added these particles to their formula is not clear. At this point, it’s not even clear why they might have been added, as hydroxyapatite does not appear to be a substantial source of calcium in most formula. (Calcium in formula can come from a number of sources, including milk solids, calcium carbonate and calcium chloride.) If the nanoparticles’ inclusion was intentional, though, current FDA guidelines suggest that the regulator wouldn’t consider the material safe by default, and should be subject to further evaluation.</p>
<p>Certainly, from the data presented, these particles – so uniform in size and shape – look like they were intentionally manufactured to be nanoscale and needle-like. It’s possible they were supplied to the various manufacturers without any indication of their “nano-ness.” This doesn’t absolve the manufacturers of responsibility. But it does suggest that greater scrutiny and accountability is needed in the supply chain for food ingredients.</p>
<p>And regardless of the benefits and risks of nanoparticles in infant formula, parents have a right to know what’s in the products they’re feeding their children. In Europe, food ingredients must be <a href="http://ec.europa.eu/food/safety/docs/labelling_legislation_infographic_food_labelling_rules_2014_en.pdf">legally labeled if they are nanoscale</a>. In the U.S., there is no such requirement, leaving American parents to feel somewhat left in the dark by producers, the FDA and policy makers.</p>
<p>Given the state of science on nanoscale hydroxyapatite in foods, this is as much an issue of trust as it is safety. The FoE report may exaggerate the possible risks, and raise concerns where few are justified. Yet it’s hard to avoid the reality that, if manufacturers are adding nanoparticles to what we feed our children, we need to know more about how to ensure their safety and benefits. How else can we enable informed decisions? </p>
<p>Luckily, current research suggests hydroxyapatite nanoparticles in formula are most likely safe, and arguably, even beneficial. But given how high the stakes are, safety here should not, and indeed cannot, be taken for granted.</p><img src="https://counter.theconversation.com/content/59246/count.gif" alt="The Conversation" width="1" height="1" />
<h4 class="border">Disclosure</h4><p class="fine-print"><em><span>Andrew Maynard receives funding support from the Center for Research on Ingredients Risk (CRIS) at Michigan State University. He is also on the Board of Trustees of the International Life Sciences Association North America. He was an independent reviewer on the Friends of the Earth report on nanoparticles in infant formula</span></em></p>Microscopic needle-like particles don’t seem like something you’d want to feed a baby. Whether safe or not, the way we deal with nanoscale food additives leaves plenty of other questions.Andrew Maynard, Director, Risk Innovation Lab, Arizona State UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/127112013-03-21T22:45:29Z2013-03-21T22:45:29ZCalcium confusion: scientists divided over supplements<figure><img src="https://images.theconversation.com/files/21489/original/26k7y7bj-1363753775.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">There's conflicting evidence about both the efficacy and the safety of taking calcium supplements.</span> <span class="attribution"><span class="source">it thatswitch/Flickr</span></span></figcaption></figure><p>A clash between supporters and detractors of calcium supplements for better bone health is leading to conflicting headlines, leaving the public unsure about whom to believe.</p>
<p>Osteoporosis is estimated to cost the Australian economy more than $7 billion a year. It’s a condition that <a href="http://www.abs.gov.au/ausstats/abs@.nsf/Lookup/4364.0.55.001chapter3102011-12">affects</a> around 700,000 Australians, the vast majority of whom are women. In 2009-10, nearly 7,000 Australians were hospitalised as a result of osteoporosis.</p>
<p>It’s accepted that limited exposure to sunlight resulting in low <a href="http://www.nrv.gov.au/nutrients/vitamin%20d.htm">vitamin D</a> intake is a risk factor contributing to osteoporosis, and the <a href="http://www.nhmrc.gov.au/">National Health and Medical Research Council</a> (NHMRC) says the combination of calcium and vitamin D can help reduce the chance of breaking bones.</p>
<p>But scientists differ on where people should get their calcium.</p>
<p>Last month, independent health experts from the US <a href="http://www.ahrq.gov/professionals/clinicians-providers/guidelines-recommendations/uspstfix.html">Preventive Services Task Force</a> said adding vitamin D and calcium to a healthy diet does not lower risk of fractures in post-menopausal women, and that for younger women and men, the studies were too inconclusive to support regular use of supplements. </p>
<p>This is despite a <a href="http://www.nhlbi.nih.gov/whi/">Women’s Health Initiative</a> study on the benefits and risks of daily calcium and low-dose vitamin D supplements finding they led to a 12% reduction in hip fractures for women aged 50-79, and a 21% reduction for women aged over 60. Those women with intakes above 1200 mg per day did not clearly get additional benefit from the intervention, suggesting that more is not necessarily better.</p>
<p>It’s clear that sufficient calcium is good for bone health, but at the heart of the recent debate over supplements are new [studies](https://theconversation.com/can-calcium-supplements-cause-heart-disease-7282](https://theconversation.com/can-calcium-supplements-cause-heart-disease-7282) linking calcium supplements with heart disease.</p>
<p>It’s a body of research that Professor Christopher Nordin, who has been working in the area of calcium metabolism and osteoporosis for more than 50 years, strongly refutes.</p>
<p>He says the evidence of benefit from calcium and vitamin D supplements is very well established, particularly for post-menopausal women, and points out that the Women’s Health Initiative study of post-menopausal women found no association between calcium supplements and heart attacks.</p>
<p>“The absorption of calcium goes down at the menopause and the urinary calcium goes up, so the requirement for calcium goes up,” Professor Nordin said.</p>
<h2>Commercially conflicted?</h2>
<p>Last month a group of doctors called for more scrutiny to be placed on the marketers of supplements, after the journal <a href="http://advances.nutrition.org/">Advances in Nutrition</a> published an article that was funded by a supplements trade association.</p>
<p>In a <a href="http://www.bmj.com/content/341/bmj.c4997">letter</a> to the editor published in the BMJ, Dr Ian Reid and colleagues from the <a href="http://www.auckland.ac.nz/uoa/">University of Auckland</a> said two of the six authors of the paper published by Advances in Nutrition are employees of the <a href="http://www.crnusa.org/">Council for Responsible Nutrition</a>, a trade association representing dietary supplement manufacturers.</p>
<p>The <a href="http://advances.nutrition.org/content/4/2/151.full?sid=2388b9d5-30ca-48e4-b444-65e0d4f1ca0e">paper</a> in question, by Dr R.P. Heaney of <a href="http://medschool.creighton.edu/medicine/departments/departmentofmedicine/divisions/endocrinology/osteoporosisresearchcenter/index.php">Creighton University’s Osteoporosis Research Centre</a>, argued the evidence presented to date on the relationship between calcium supplement use and increased cardiovascular disease risk was not sufficient to warrant a change in the Institute of Medicine recommendations, which advocates the use of supplements to promote bone health in people who do not get the recommended intake of calcium through their diet.</p>
<p>Dr Reid said it was a concern that the literature was being influenced by groups, such as CRN.</p>
<p>While the support of the CRN for the study in question was disclosed in the Advances in Nutrition article, Dr Reid said it was part of larger and carefully coordinated press campaign to promote a view that was commercially advantageous to the CRN and its members.</p>
<p>“The thing that struck about it was the blatancy with which it was done, and that really contrasts dramatically with what happens in the pharmaceutical arena. Most academics go to great strains not to be seen to be captured by any lobby group,” Dr Reid said.</p>
<p>However, Professor Nordin said there was very little profit and negligible industrial contribution from calcium and vitamin D supplements.</p>
<p>He went further and argued Dr Reid had no right to criticise Dr Heaney because he had in the past received funding support from Fonterra, a New Zealand multinational owned by dairy farmers.</p>
<p>Dr Reid said he had not received any funding from the dairy industry in the last three years and none of his calcium studies had been funded by them.</p>
<p>A paper by Dr Reid published in the BMJ in 2010 disclosed that he had previously received research support from, and acted as a consultant for, Fonterra.</p>
<p>Professor Nordin said he once received a grant from Roche who manufacture a form of vitamin D called calcitriol, and 60 years ago he received a travel grant from Sandoz who used to market a calcium preparation.</p>
<h2>Journals and responsibility</h2>
<p>Dr Reid argues academic journals need to be very aware of potential conflicts of interest, and is concerned there may be a double standard when it comes to supplements.</p>
<p>“I’m not confident in the supplements space generally that the levels of scrutiny are what we would expect in other areas such as the pharmaceuticals area,” he said.</p>
<p>However, physician and health ethicist Paul Komesaroff said as long as the partisan nature of the argument was openly stated, there was nothing wrong with scientists arguing the case for the manufacturers of calcium supplementation.</p>
<p>“Whether Heaney is employed by the drug industry or not does not invalidate his argument,” Professor Komesaroff said.</p>
<p>“In a court of law we are comfortable to accept the role of an advocate for a particular point of view - with the provision that the allegiance of the advocate is openly stated - and I can see no reason why we should not be equally happy with such a system in science.”</p>
<p>Professor Komesaroff added that despite claims to the contrary, no scientific argument is free from interests of some kind or other.</p>
<p>“Scientists like to think of themselves as radically sceptical, but this is far from the case. Indeed, it is well recognised that scientists become very attached to their own points of view and tend to resist change, even in the face of strongly contrary evidence.”</p>
<p>However, Dr Reid said there were other ways for supplement manufacturers to reach the market.</p>
<p>“If something is dressed up as an objective review and published in an academic journal then that is a less acceptable way for supplement manufacturers to express their point of view,” Dr Reid said.</p>
<p>The publisher and editor of Advances in Nutrition did not respond to our request for comment.</p>
<h2>Natural is best</h2>
<p>The NHMRC <a href="http://www.nrv.gov.au/nutrients/calcium.htm">recommends</a> adults have a daily intake of calcium of 1,000 milligrams per day, and this rises for women aged over 50 to 1,300 milligrams per day to account for increased need at menopause. It recommends an upper limit of 2,500 milligrams per day, with the rationale that adding 1,000 mg of calcium to a typical western diet would only increase calcium in urine by about 60 mg.</p>
<p>Vitamin D, made in the body by the action of sunlight on the skin, is also critically important, because it helps the body to absorb calcium.</p>
<p>The guidelines are similar in the United States, however the <a href="http://www.ahrq.gov/professionals/clinicians-providers/guidelines-recommendations/uspstfix.html">US Preventative Services Task Force</a> says more evidence is required to “assess the balance of the benefits and harms of daily supplementation with greater than 400 International Units of vitamin D and greater than 1,000 mg of calcium for the primary prevention of fractures in non-institutionalised postmenopausal women”.</p>
<p>Based on the available evidence, the strongest argument is that people should try to get their daily intake of calcium and vitamin D by eating a diet rich in these nutrients. For postmenopausal women, the benefits of supplements appear to outweigh the risks. With more research, the case for and against supplements is expected to become
clearer.</p><img src="https://counter.theconversation.com/content/12711/count.gif" alt="The Conversation" width="1" height="1" />
A clash between supporters and detractors of calcium supplements for better bone health is leading to conflicting headlines, leaving the public unsure about whom to believe. Osteoporosis is estimated to…Reema Rattan, Global Commissioning EditorCharis Palmer, Deputy Editor/Chief of StaffLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/72822012-06-20T20:44:39Z2012-06-20T20:44:39ZCan calcium supplements cause heart disease?<figure><img src="https://images.theconversation.com/files/11385/original/4dm79x8k-1338861850.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">There’s no evidence suggesting that a calcium-rich diet causes heart problems.</span> <span class="attribution"><span class="source">Rachel James</span></span></figcaption></figure><p>People taking calcium supplements to mitigate their risk of developing bone disease (osteoporosis) may be doing more harm to their health than good. That’s because a growing body of research shows the supplements confer little benefit and increase the risk of developing heart disease. </p>
<p>Calcium supplements have also traditionally been thought to reduce the risk of heart attacks because they produce small beneficial changes in both blood pressure and blood cholesterol levels. We set out to test this idea in a trial we had originally designed to check the effect of calcium supplements on fractures and bone density. </p>
<p>To our surprise, what we <a href="http://www.bmj.com/content/336/7638/262">discovered</a> was that heart attacks were actually more common in the (randomly selected) women who received calcium supplements than those who had randomly been given inactive tablets.</p>
<p>When we <a href="http://www.bmj.com/content/336/7638/262">published this study</a> in the <a href="http://www.bmj.com/">British Medical Journal</a> in 2008, it caused widespread surprise among doctors working in the area, as well as the general public. So to test whether this was the true effect of calcium supplements, we decided to do a <a href="https://theconversation.com/how-do-we-know-what-works-systematic-research-reviews-5979">meta-analysis</a> of studies about taking them.</p>
<p>First, we contacted all the researchers who had carried out large trials of calcium supplements in the past to see whether they’d kept records of the medical problems that occurred in the course of the trials. </p>
<p>Data were available from 93% of trial subjects (almost 12,000 people) and these confirmed our finding that women who received calcium tablets in the studies had a 20% to 30% <a href="http://aura.abdn.ac.uk/bitstream/2164/756/1/Bolland%202010.pdf">increase in heart attack risk</a>. </p>
<p>We subsequently added to this database the results from other trials in which the <a href="http://www.bmj.com/content/342/bmj.d2040">intervention was calcium and vitamin D</a>, rather than calcium alone. This showed the same effect – a 25% increase in the risk of heart attacks and a 15% increase in the risk of stroke. </p>
<p>These results were based on almost 29,000 people participating in research and so were much more reliable than the results we had published previously. </p>
<p>From these analyses, we were able to determine that the number of heart attacks and strokes apparently caused by calcium supplements was greater than the number of fractures that they appeared to prevent. Naturally, we concluded that the use of calcium tablets was likely to be doing more harm than good and should be discontinued.</p>
<p>It’s very important to note that none of our analyses included the effect of calcium-rich foods, and there’s really no evidence suggesting that a calcium-rich diet causes heart problems.</p>
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<img alt="" src="https://images.theconversation.com/files/11382/original/mgdzxkbc-1338861666.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/11382/original/mgdzxkbc-1338861666.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=844&fit=crop&dpr=1 600w, https://images.theconversation.com/files/11382/original/mgdzxkbc-1338861666.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=844&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/11382/original/mgdzxkbc-1338861666.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=844&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/11382/original/mgdzxkbc-1338861666.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1060&fit=crop&dpr=1 754w, https://images.theconversation.com/files/11382/original/mgdzxkbc-1338861666.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1060&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/11382/original/mgdzxkbc-1338861666.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1060&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<span class="attribution"><span class="source">Matt Reinbold</span></span>
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<p>The reason for the difference between tablet supplements and food remains uncertain, but it may be related to the increase in blood calcium level that’s seen for several hours following the large dose of calcium in tablet form. In contrast, calcium in food is absorbed more slowly and has very little impact on blood calcium levels. </p>
<p>Elevations of blood calcium levels have previously been shown to <a href="http://onlinelibrary.wiley.com/doi/10.1111/j.1365-2265.2010.03792.x/full">increase the risk of heart disease</a>, possibly through producing calcium deposits in the walls of blood vessels and accelerated arterial disease.</p>
<p>A number of <a href="http://www.sciencedirect.com/science/article/pii/S0378512209000954">other researchers have now looked</a> into these questions. This month, <a href="http://heart.bmj.com/content/98/12/920.full.pdf">researchers from Germany reported</a> that individuals taking calcium supplements appear to almost double the risk of heart attacks compared with people not taking supplements. And again, those who have high dietary calcium intakes tend toward lower risk of heart disease. </p>
<p>The German study didn’t randomly assign participants into groups taking calcium or placebo tablets, but simply reported events in individuals who had made the decision to take supplements independently. This is a less reliable way of determining the effects of an intervention than a randomised trial. Nonetheless, this observational study provides supportive evidence for the results of our trial analyses.</p>
<p>Last year, <a href="http://www.sciencedirect.com/science/article/pii/S0378512211001526">researchers in Sydney studied</a> the effects of calcium supplements in a very elderly group of individuals living in hostels. One-third of the 600 people in the group died during follow up. Death rates increased by 47% in those randomised to calcium and death from heart disease was increased by 76%.</p>
<p>So the weight of evidence that calcium supplements are bad for the heart has steadily increased. What, then, should people do in the face of these findings? </p>
<p>Calcium supplements are mainly used to reduce the risk of fractures from osteoporosis (a bone disease that leads to increased likelihood of fracture). But there are other important measures that will also contribute to osteoporosis prevention, such as regular exercise, not smoking, maintaining a healthy body weight, regular sunlight exposure to maintain vitamin D levels, and removal of falls hazards in the home (such as loose rugs, power cords, and slippery floors). </p>
<p>A steady supply of calcium is important for bone health, but research clearly shows this should be derived from a balanced diet that includes several servings of dairy products, or other calcium sources, such as dark green vegetables or tofu. </p>
<p>Women in their 60s and men in their 70s should have their risk of osteoporotic fractures formally assessed. This usually involves bone density measurement. </p>
<p>People found to be at high risk of fractures should consider using one of the medicines proven to safely reduce fracture risk. This is likely to be more effective than relying on the weak anti-osteoporotic effects of calcium supplements, which come at an unacceptably high price – the increased risk of heart disease.</p><img src="https://counter.theconversation.com/content/7282/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Ian Reid consults to Sanofi and receives funding from Health Research Council of New Zealand.</span></em></p>People taking calcium supplements to mitigate their risk of developing bone disease (osteoporosis) may be doing more harm to their health than good. That’s because a growing body of research shows the…Ian Reid, Deputy Dean & Professor of Medicine, University of Auckland, Waipapa Taumata RauLicensed as Creative Commons – attribution, no derivatives.