tag:theconversation.com,2011:/us/topics/oxidative-stress-1742/articlesOxidative stress – The Conversation2022-08-29T12:39:49Ztag:theconversation.com,2011:article/1874222022-08-29T12:39:49Z2022-08-29T12:39:49ZExtreme heat and air pollution can be deadly, with the health risk together worse than either alone<figure><img src="https://images.theconversation.com/files/481425/original/file-20220828-7442-4j6f2d.jpg?ixlib=rb-1.1.0&rect=37%2C37%2C3551%2C2355&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Bad air pollution and extreme heat each raise health risks, but they're worse combined.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/los-angeles-resident-carmen-green-jumps-rope-at-a-closed-news-photo/1228565250">Brian van der Brug/Los Angeles Times via Getty Images</a></span></figcaption></figure><p>Heat waves and air pollution from wildfire smoke and other sources are <a href="https://doi.org/10.1001/jama.2017.17923">each problematic</a> for <a href="https://doi.org/10.1016/S0140-6736(21)01208-3">human health</a>, particularly for vulnerable populations such as older adults. But what happens when they hit at the same time?</p>
<p>We examined over 1.5 million deaths from 2014 to 2020 registered in California – a state prone to summer heat waves and air pollution from wildfires – to find out.</p>
<h2>Deaths spike when both risks are high</h2>
<p>The number of deaths rose both on hot days and on days with high levels of fine particulate air pollution, <a href="https://www.health.ny.gov/environmental/indoors/air/pmq_a.htm">known as PM2.5</a>. But on days when an area was hit with a double whammy of both high heat and high air pollution, the effects were much higher than for each condition alone.</p>
<p>The risk of death on those extra-hot and polluted days was about <a href="https://doi.org/10.1164/rccm.202204-0657OC">three times greater</a> than the effect of either high heat or high air pollution alone.</p>
<p>The more extreme the temperatures and pollution, the <a href="https://doi.org/10.1164/rccm.202204-0657OC">higher the risk</a>. During the top 10% of hottest and most polluted days, the risk of death increased by 4% compared to days without extremes. During the top 1%, it increased by 21%; and among older adults over age 75, the risk of death increased by more than a third on those days.</p>
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<h2>Why risks are higher when both hit at once</h2>
<p>There are several ways the combined exposure to extreme heat and particulate air pollution can harm human health.</p>
<p>Oxidative stress is the most common biological pathway linked with particulate air pollution and heat exposure. <a href="https://doi.org/10.1038/s41573-021-00233-1">Oxidative stress</a> is an imbalance between production of highly reactive molecules known as reactive oxygen species, or ROS, and the body’s ability to remove them. It’s been linked with <a href="https://link.springer.com/chapter/10.1007/978-981-32-9366-3_5">lung diseases</a>, among other illnesses. </p>
<p>Antioxidants help clean up these molecules, but particulate air pollution and heat disrupt this balance through excessive metabolic ROS production and lowered antioxidant activity.</p>
<p>Our research also showed that the effects of particulate air pollution and heat extremes were <a href="https://doi.org/10.1164/rccm.202204-0657OC">larger when high nighttime temperature and pollution occurred together</a>. High nighttime temperatures can <a href="https://doi.org/10.1016/S2542-5196(22)00139-5">interfere with normal sleep</a> and potentially contribute to chronic health conditions such as <a href="https://jamanetwork.com/journals/jamainternalmedicine/fullarticle/215006">heart disease</a> and <a href="https://www.pnas.org/doi/full/10.1073/pnas.1216951110">obesity</a>, and disrupt how the body regulates temperature.</p>
<p>Older adults may be more susceptible to effects of extreme heat and air pollution exposure, in part because this stress comes on top of age-related chronic health conditions like heart disease, high blood pressure, diabetes or chronic lung disease. <a href="https://www.ncbi.nlm.nih.gov/books/NBK507838/">Impaired body temperature regulation</a> in response to heat can also occur with aging. And older adults may be less mobile and therefore less able to get to cooling centers or to medical care and be less able to afford air conditioning. </p>
<h2>A future of high temperatures and air pollution</h2>
<p>This isn’t just a California problem. Climate change will increase exposure to high heat and air pollution in many parts of the country. </p>
<p>Yearly average temperatures in the U.S. are already more than 1.8 degrees Fahrenheit (1 degree Celsius) warmer than at the beginning of the 1900s. By the end of this century, global temperatures are on pace to be <a href="https://www.unep.org/resources/emissions-gap-report-2021">nearly 5 F (2.7 C) warmer</a>. Dangerous extreme heat waves, currently rare, will <a href="https://science2017.globalchange.gov/chapter/6/">become more common</a>. </p>
<p>Changing climate is also <a href="http://doi.org/10.1016/j.amepre.2008.08.025">affecting levels</a> of outdoor fine particulate pollution – for example, through weather changes such as air stagnation events, wind and dust storms, and drier and warmer conditions that <a href="https://nca2018.globalchange.gov/chapter/13/">contribute to increasingly frequent and intense wildfires</a>.</p>
<h2>What to do to stay safe</h2>
<p>Further research is needed to better understand these effects, such as the full impact of wildfire smoke exposure. However, enough is known that people should take measures to reduce their risk of harm during periods of extreme heat or air pollution.</p>
<p>That means staying <a href="https://www.cdc.gov/disasters/extremeheat/heattips.html">well hydrated and keeping cool</a>. Shopping malls and other air-conditioned public spaces can provide a refuge from heat. Home air conditioning, especially during nighttime, can reduce mortality. A portable air filter in the bedroom can <a href="https://onlinelibrary.wiley.com/doi/full/10.1111/ina.12753">markedly reduce particle pollution levels</a>.</p>
<p>People with <a href="https://www.cdc.gov/disasters/extremeheat/warning.html">symptoms of heat stress</a>, such as headache, nausea, dizziness or confusion, especially the elderly, should seek medical care. </p>
<p>Many county and state health departments already provide alerts about extreme heat and extreme air pollution. Developing a special category of alert during co-occurring extremes may be beneficial to public health.</p>
<p>Governments also need to take steps now to avoid the worst future climate change scenarios. Some best practices for cities include creating cooling shade cover and green space that will also reduce particle pollution.</p><img src="https://counter.theconversation.com/content/187422/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Erika Garcia receives support from Southern California Environmental Health Sciences Center, National Institute of Environmental Health Sciences grant P30ES007048, and the University of Southern California Office of Research Strategic Development of Research Award.</span></em></p><p class="fine-print"><em><span>Rob Scot McConnell receives funding from the National Institute of Environmental Health Sciences</span></em></p><p class="fine-print"><em><span>Md Mostafijur Rahman 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>The worst effects are during high nighttime temperatures, something happening more often with climate change. Wildfire smoke adds to the risk.Erika Garcia, Assistant Professor of Population and Public Health Sciences, University of Southern CaliforniaMd Mostafijur Rahman, Postdoctoral Scholar and Research Associate in Environmental Health, University of Southern CaliforniaRob Scot McConnell, Professor of Population and Public Health Sciences, University of Southern CaliforniaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1864452022-07-19T12:25:44Z2022-07-19T12:25:44ZCells become zombies when the ends of their chromosomes are damaged – a tactic both helpful and harmful for health<figure><img src="https://images.theconversation.com/files/473984/original/file-20220713-9184-rhhs18.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C3000%2C2213&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Telomeres (red) at the ends of chromosomes protect your DNA from damage.</span> <span class="attribution"><a class="source" href="https://flic.kr/p/JUr1Ay">Thomas Ried/NCI Center for Cancer Research, National Cancer Institute, National Institutes of Health via Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by-nc/4.0/">CC BY-NC</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>Damage to the ends of your chromosomes can create “zombie cells” that are still alive but can’t function, according to our recently published study in <a href="https://doi.org/10.1038/s41594-022-00790-y">Nature Structural and Molecular Biology</a>.</p>
<p>When cells prepare to divide, their DNA is tightly wound around proteins to form chromosomes that provide structure and support for genetic material. At the ends of these chromosomes are repetitive stretches of DNA called <a href="https://www.genome.gov/genetics-glossary/Telomere">telomeres</a> that form a protective cap to prevent damage to the genetic material. However, telomeres shorten each time a cell divides. This means that as cells divide more and more as you age, your telomeres become increasingly shorter and more likely to lose their ability to protect your DNA.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/474165/original/file-20220714-32290-qampef.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Diagram depicting chromosomes in the nucleus, highlighting the telomeres at the ends of each DNA-containing arm." src="https://images.theconversation.com/files/474165/original/file-20220714-32290-qampef.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/474165/original/file-20220714-32290-qampef.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=381&fit=crop&dpr=1 600w, https://images.theconversation.com/files/474165/original/file-20220714-32290-qampef.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=381&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/474165/original/file-20220714-32290-qampef.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=381&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/474165/original/file-20220714-32290-qampef.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=479&fit=crop&dpr=1 754w, https://images.theconversation.com/files/474165/original/file-20220714-32290-qampef.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=479&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/474165/original/file-20220714-32290-qampef.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=479&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Telomeres serve as protective caps at the ends of each chromosome.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/illustration/telomere-chromosome-and-dna-royalty-free-illustration/961320764">FancyTapis/iStock via Getty Images</a></span>
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<p>Damage to genetic material can lead to mutations that cause cells to divide uncontrollably, resulting in cancer. Cells avoid becoming cancerous when their telomeres become too short after dividing too many times and potentially accruing damage along the way, however, by entering a zombielike state that stops cells from from dividing through a process called <a href="https://doi.org/10.7554/eLife.72449">cellular senescence</a>.</p>
<p>Because they are resistant to death, senescent – or “zombie” – cells accumulate with age. They can be beneficial to health by promoting senescence in nearby cells at risk of becoming cancerous and attracting immune cells to clear out cancer cells. But they can also contribute to disease by impairing tissue healing and immune function, and by secreting chemicals that promote inflammation and tumor growth.</p>
<p>We wanted to know if direct damage to telomeres can be sufficient to trigger senescence and make zombie cells. In order to figure this out, we needed to confine damage just to the telomeres. So we attached a protein to the telomeres of human cells grown in the lab. Then we added a dye to the protein that makes it sensitive to light. Shining a far-red light (or light with a wavelength slightly shorter than infrared light) on the cells induces the protein to produce oxygen <a href="https://www.verywellhealth.com/information-about-free-radicals-2249103">free radicals</a> – highly reactive molecules that can damage DNA – right at the telomeres, sparing the rest of the chromosome and the cell.</p>
<p>We found that direct damage to the telomeres was sufficient to turn cells into zombies, even when these protective caps weren’t shortened. The reason for this, we discovered, was likely a result of <a href="https://doi.org/10.1038%2Fncb2897">disrupted DNA replication</a> at the telomeres that leaves chromosomes even more susceptible to damage or mutations. </p>
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<a href="https://images.theconversation.com/files/473987/original/file-20220713-13035-8w2uvc.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Microscopy image of chromosomes with telomeres damaged by oxidation" src="https://images.theconversation.com/files/473987/original/file-20220713-13035-8w2uvc.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/473987/original/file-20220713-13035-8w2uvc.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=348&fit=crop&dpr=1 600w, https://images.theconversation.com/files/473987/original/file-20220713-13035-8w2uvc.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=348&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/473987/original/file-20220713-13035-8w2uvc.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=348&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/473987/original/file-20220713-13035-8w2uvc.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=437&fit=crop&dpr=1 754w, https://images.theconversation.com/files/473987/original/file-20220713-13035-8w2uvc.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=437&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/473987/original/file-20220713-13035-8w2uvc.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=437&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 telomeres (green) at the tips of chromosomes (blue) damaged by free radicals become fragile (green arrows) and trigger senescence.</span>
<span class="attribution"><a class="source" href="https://doi.org/10.1038/s41594-022-00790-y">Ryan Barnes/Opresko Lab</a>, <a class="license" href="http://creativecommons.org/licenses/by-nc-nd/4.0/">CC BY-NC-ND</a></span>
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<h2>Why it matters</h2>
<p>Telomeres naturally shorten with age. They limit how many times a cell can divide by signaling cells to become zombies when they reach a certain length. But an excess of free radicals produced from both normal bodily processes as well as exposure to harmful chemicals like air pollution and tobacco smoke can lead to a condition called <a href="https://doi.org/10.1016/j.mad.2018.03.013">oxidative stress</a> that can accelerate telomere shortening. This can prematurely trigger senescence and contribute to age-related diseases, including <a href="https://doi.org/10.1172/jci120216">immunodeficiency</a>, <a href="https://doi.org/10.1038%2Fs41556-022-00842-x">cardiovascular disease</a>, <a href="https://doi.org/10.1038/nrg3246">metabolic disease</a> and <a href="https://doi.org/10.1016%2Fj.cell.2020.12.028">cancer</a>.</p>
<p>Our study reveals that telomeres not only serve as alarm clocks that indicate a cell divided too many times, but also as warning bells for harmful levels of oxidative stress. Age-related shortening of telomeres isn’t the only thing that triggers senescence; telomere damage is also sufficient to turn a cell into a zombie.</p>
<h2>What other research is being done</h2>
<p>Researchers are studying treatments and interventions that can protect telomeres from damage and prevent zombie cell accumulation. A number of studies in mice have found that removing zombie cells can promote healthy aging by improving <a href="https://doi.org/10.1111/acel.13296">cognitive function</a>, <a href="https://doi.org/10.1038/nature10600">muscle mass and function</a> and recovery from <a href="https://doi.org/10.1126/science.abe4832">viral infections</a>. </p>
<p>Researchers are also developing drugs called <a href="https://doi.org/10.1146/annurev-pharmtox-050120-105018">senolytics</a> that can either kill zombie cells or prevent them from developing in the first place.</p>
<h2>What’s next</h2>
<p>This study focuses on the consequences of telomere damage in actively dividing cells, like kidney and skin cells. We’re now looking at how this damage will play out in cells that don’t divide, like neurons or heart muscle cells. While researchers have shown that the telomeres of nondividing cells and tissues <a href="https://doi.org/10.1038/s41556-022-00842-x">become more dysfunctional with age</a>, it’s unclear why this happens when these telomeres should not be shortening in the first place.</p><img src="https://counter.theconversation.com/content/186445/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Patricia Opresko receives funding from the National Institutes of Health and has received funding from the Glenn Foundation for Medical Research. </span></em></p><p class="fine-print"><em><span>Ryan Barnes receives funding from:
NIA F32AG067710-01
NIEHS K99ES033771</span></em></p>The protective caps at the ends of chromosomes naturally shorten over time. Researchers found that direct damage can prematurely trigger senescence and contribute to age-related diseases like cancer.Patricia Opresko, Professor of Environmental and Occupational Health, University of PittsburghRyan Barnes, Postdoctoral Researcher in Environmental and Occupational Health, University of PittsburghLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1277282019-12-05T01:45:05Z2019-12-05T01:45:05ZTick, tock… how stress speeds up your chromosomes’ ageing clock<figure><img src="https://images.theconversation.com/files/305098/original/file-20191204-70126-7cple3.jpg?ixlib=rb-1.1.0&rect=0%2C216%2C4380%2C3244&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">At a molecular level, stresses and strains can make your body clock break into a sprint.</span> <span class="attribution"><span class="source">Lightspring/Shutterstock</span></span></figcaption></figure><p>Ageing is an inevitability for all living organisms, and although we still don’t know exactly why our bodies gradually grow ever more decrepit, we are starting to grasp how it happens.</p>
<p>Our new research, <a href="https://onlinelibrary.wiley.com/doi/full/10.1111/ele.13426">published in Ecology Letters</a>, pinpoints factors that influence one of the most important aspects of the ageing process, at the fundamental level of our DNA. It suggests how stress can cause the biochemical body clock built into our chromosomes to tick faster.</p>
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Read more:
<a href="https://theconversation.com/the-search-to-extend-lifespan-is-gaining-ground-but-can-we-truly-reverse-the-biology-of-ageing-75127">The search to extend lifespan is gaining ground, but can we truly reverse the biology of ageing?</a>
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<p>DNA - the genetic material in our cells - does not float freely in cells’ nuclei, but is organised into clumps called chromosomes. When a cell divides and produces a replica of itself, it has to make a copy of its DNA, and because of the way this process works, a tiny portion is always lost at one end of each DNA molecule. </p>
<p>To protect vital portions of DNA from being lost in the process, the ends of chromosomes are capped with special sequences called <a href="https://www.britannica.com/science/telomere">telomeres</a>. These are gradually whittled away during successive cell divisions.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/305097/original/file-20191204-70149-nj759j.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/305097/original/file-20191204-70149-nj759j.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/305097/original/file-20191204-70149-nj759j.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=472&fit=crop&dpr=1 600w, https://images.theconversation.com/files/305097/original/file-20191204-70149-nj759j.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=472&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/305097/original/file-20191204-70149-nj759j.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=472&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/305097/original/file-20191204-70149-nj759j.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=593&fit=crop&dpr=1 754w, https://images.theconversation.com/files/305097/original/file-20191204-70149-nj759j.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=593&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/305097/original/file-20191204-70149-nj759j.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=593&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">Telomeres (highlighted in white) are like molecular buffers for your chromosomes.</span>
<span class="attribution"><a class="source" href="http://science.nasa.gov/media/medialibrary/2006/03/16/22mar_telomeres_resources/caps.gif">US Dept of Energy Human Genome Program</a></span>
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<p>This gradual loss of telomeres acts like a cellular clock: with each replication they get shorter, and at a certain point they become too short, forcing the cell into a programmed death process. The key question is what this process, which plays out on a cellular level, actually means for our mortality. Does the fate of individual cells really matter so much? Does the ticking telomere clock really count down the remaining time our bodies have to live?</p>
<p>Cellular ageing is just one of many components of ageing - but it’s one of the most important. Gradual deterioration of our body’s tissues, and the irreversible death of our cells, are responsible for the most conspicuous effects of ageing such as loss of physical fitness, deterioration of connective tissues leading to skin wrinkles, or neurodegenerative diseases such as Parkinson’s disease.</p>
<h2>What makes us tick?</h2>
<p>Another crucial question is: are there factors that speed up or slow down the loss of our ticking telomeres? </p>
<p>So far, our answers to this question have been incomplete. Studies have provided glimpses of possible mechanisms, suggesting that things like <a href="https://science.sciencemag.org/content/347/6220/436/tab-figures-data">infections</a> or even <a href="https://onlinelibrary.wiley.com/doi/full/10.1111/jeb.12479">dedicating extra energy to reproduction</a> might accelerate telomere shortening and speed up cellular ageing. </p>
<p>This evidence is piecemeal, but these factors all seem to have one thing in common: they cause “physiological stress”. Broadly speaking, our cells are stressed when their biochemical processes are disrupted, either by a lack of resources or for some other reason. If cells lose too much water, for example, we might say they are in “dehydration stress”.</p>
<p>More familiar types of stress also count. Tiredness and overwork put us under chronic stress, as does feeling anxious for prolonged periods. <a href="https://www.sciencedaily.com/releases/2018/07/180712141715.htm">Lack of sleep</a> or <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2763246/">emotional stress</a> can alter internal cellular pathways, including telomere functioning.</p>
<p>With this in mind, we asked ourselves one simple question. Can various types of stress experienced by an individual actually accelerate their rate of ageing?</p>
<h2>Stress and strain</h2>
<p>In our research, led by my colleague Marion Chatelain of the University of Warsaw (currently University of Innsbruck), we chose to look at this question as broadly as possible. Many studies have looked at this problem in specific species, such as mice, rats, and various fish and bird species (both wild and in the lab). We compiled the available evidence into a summary of the existing knowledge, across all vertebrate organisms studied so far.</p>
<p>The emerging picture clearly suggests that telomere loss is profoundly impacted by stress. All else being equal, stress does indeed hasten telomere loss and accelerate the internal cellular clock. </p>
<p>Importantly, the type of stress matters: by far the strongest negative impact is caused by pathogen infections, competition for resources, and intensive investment in reproduction.</p>
<p>Other stressors, such as poor diet, human disturbance or urban living, also hastened cellular ageing, although to a lesser extent.</p>
<h2>Getting radical</h2>
<p>A natural question arises: what makes stress exert such a powerful influence on cellular clocks? Is there a single mechanism, or many? Our analysis may have identified one possible candidate: “oxidative stress”. </p>
<p>When cells are stressed, this often manifests itself through an accumulation of oxidising molecules, such as <a href="https://theconversation.com/health-check-the-untrue-story-of-antioxidants-vs-free-radicals-15920">free radicals</a>. Residing at the exposed ends of our chromosomes, telomeres are perfect targets for attack by these chemically reactive molecules. </p>
<p>Our analysis suggests that, regardless of the type of stress experienced, this oxidative stress might be the actual biochemical process that links stress and telomere loss. As to whether this means that we should eat more <a href="https://www.britannica.com/science/antioxidant">antioxidants</a> to guard our telomeres, this certainly requires more research.</p>
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Read more:
<a href="https://theconversation.com/health-check-the-untrue-story-of-antioxidants-vs-free-radicals-15920">Health Check: the untrue story of antioxidants vs free radicals</a>
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<p>I know what you’re wondering: does this mean we have discovered the secret of ageing? Can we use this knowledge to slow the ageing process or stop it in its tracks? The short answer is: no. </p>
<p>Ageing is too fundamental to our biology to get rid of it completely. But our study does underline an important truth: by reducing stress, we can do our bodies a big favour. </p>
<p>In the modern world, it is hard to escape stress completely, but we can make everyday decisions to reduce it. Get enough sleep, drink enough water, eat healthily and don’t push yourself too hard. It won’t buy you eternal life, but it should keep your cells ticking along nicely.</p>
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<p><em>The author thanks his colleagues <a href="https://www.uibk.ac.at/ecology/staff/persons/chatelain.html.en">Marion Chatelain</a> and <a href="https://cent.uw.edu.pl/en/person/prof-marta-szulkin/">Marta Szulkin</a> for their contributions to this article and the research on which it is based.</em></p><img src="https://counter.theconversation.com/content/127728/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Szymek Drobniak works for the University of New South Wales and the Jagiellonian University in Poland. He receives funding from the Australian Research Council. He is also a member of the Evolutionary Knowledge for Everyone association, the European Society for Evolutionary Biology and the Society for the Study of Evolution.</span></em></p>Emerging evidence suggests that prolonged stress exposure can accelerate the ticking rate of an internal cellular clock. By doing so, stress can contribute to faster ageing and body deterioration.Szymek Drobniak, DECRA Fellow, UNSW SydneyLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1170962019-07-31T20:04:09Z2019-07-31T20:04:09ZAre there certain foods you can eat to reduce your risk of Alzheimer’s disease?<figure><img src="https://images.theconversation.com/files/285271/original/file-20190723-110187-nwaqv6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Eating healthy foods doesn't just improve our physical health. It can benefit our mental health, too.</span> <span class="attribution"><span class="source">From shutterstock.com</span></span></figcaption></figure><p>With the rise of fad diets, “superfoods”, and a growing range of dietary supplement choices, it’s sometimes hard to know what to eat.</p>
<p>This can be particularly relevant as we grow older, and are trying to make the best choices to minimise the risk of health problems such as high blood pressure, obesity, type 2 diabetes, and heart (cardiovascular) problems. </p>
<p>We now have evidence these health problems <a href="https://www.ncbi.nlm.nih.gov/pubmed/25142458">also all affect brain function</a>: they increase nerve degeneration in the brain, leading to a higher risk of Alzheimer’s disease and other brain conditions including vascular dementia and Parkinson’s disease.</p>
<p>We know a healthy diet can protect against conditions like type 2 diabetes, obesity and heart disease. Fortunately, evidence shows that what’s good for the body is <a href="https://yourbrainmatters.org.au/diet-the-evidence-base">generally also good for the brain</a>.</p>
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<strong>
Read more:
<a href="https://theconversation.com/people-living-in-rural-areas-may-be-at-lower-risk-of-alzheimers-disease-112417">People living in rural areas may be at lower risk of Alzheimer's disease</a>
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<h2>Oxidative stress</h2>
<p>As we age, our metabolism becomes less efficient, and is less able to get rid of compounds generated from what’s called “oxidative stress”.</p>
<p>The body’s normal chemical reactions can sometimes cause chemical damage, or generate side-products known as free radicals – which in turn cause damage to other chemicals in the body.</p>
<p>To neutralise these free radicals, our bodies draw on protective mechanisms, in the form of antioxidants or specific proteins. But as we get older, these systems become less efficient. When your body can no longer neutralise the free radical damage, it’s under oxidative stress.</p>
<p>The toxic compounds generated by oxidative stress steadily build up, slowly damaging the brain and eventually leading to symptoms of Alzheimer’s disease.</p>
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<em>
<strong>
Read more:
<a href="https://theconversation.com/what-causes-alzheimers-disease-what-we-know-dont-know-and-suspect-75847">What causes Alzheimer’s disease? What we know, don’t know and suspect</a>
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<p>To reduce your risk, you need to <a href="https://www.ncbi.nlm.nih.gov/pubmed/26682690">reduce oxidative stress</a> and the long-term inflammation it can cause. </p>
<p>Increasing physical activity is important. But here we are focusing on diet, which is our major source of ANTIoxidants.</p>
<h2>Foods to add</h2>
<p>There are plenty of foods you can include in your diet that will positively influence brain health. These include fresh fruits, seafood, green leafy vegetables, pulses (including beans, lentils and peas), as well as nuts and healthy oils.</p>
<p><strong>Fish</strong></p>
<p>Fish is a good source of complete protein. Importantly, oily fish in particular is rich in omega-3 fatty acids.</p>
<p>Laboratory studies have shown omega-3 fatty acids <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6236236/">protect against oxidative stress</a>, and they’ve been found to be lacking in the brains of people with Alzheimer’s disease.</p>
<p>They are essential for memory, learning and cognitive processes, and <a href="https://www.ncbi.nlm.nih.gov/pubmed/30205543">improve the gut microbiota and function</a>.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/285272/original/file-20190723-110149-1qlz6a.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/285272/original/file-20190723-110149-1qlz6a.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/285272/original/file-20190723-110149-1qlz6a.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/285272/original/file-20190723-110149-1qlz6a.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/285272/original/file-20190723-110149-1qlz6a.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/285272/original/file-20190723-110149-1qlz6a.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/285272/original/file-20190723-110149-1qlz6a.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">
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<span class="caption">Oily fish, like salmon, is high in omega-3 fatty acids, which research shows can benefit our brain health.</span>
<span class="attribution"><span class="source">From shutterstock.com</span></span>
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<p>Low dietary intake of omega-3 fatty acids, meanwhile, is linked to <a href="https://www.ncbi.nlm.nih.gov/pubmed/28466678">faster cognitive decline</a>, and the development of preclinical Alzheimer’s disease (changes in the brain that can be seen several years before for onset of symptoms such as memory loss). </p>
<p>Omega-3 fatty acids are generally lacking in western diets, and this has been linked to <a href="https://www.ncbi.nlm.nih.gov/pubmed/27825512">reduced brain cell health and function</a>.</p>
<p>Fish also provides vitamin D. This is important because a lack of vitamin D <a href="https://www.ncbi.nlm.nih.gov/pubmed/23042216">has been linked</a> to Alzheimer’s disease, Parkinson’s disease, and vascular dementia (a common form of dementia caused by reduced blood supply to the brain as a result of a series of small strokes).</p>
<p><strong>Berries</strong></p>
<p>Berries are especially high in the antioxidants vitamin C (strawberries), anthocyanins (blueberries, raspberries and blackberries) and resveratrol (blueberries).</p>
<p>In research conducted on mouse brain cells, anthocyanins have been associated with lower toxic Alzheimer’s disease-related protein changes, and <a href="https://www.ncbi.nlm.nih.gov/pubmed/28931353">reduced signs of oxidative stress and inflammation</a> specifically related to <a href="https://www.ncbi.nlm.nih.gov/pubmed/29401686">brain cell (neuron) damage</a>. Human studies have shown <a href="https://www.ncbi.nlm.nih.gov/pubmed/28249119">improvements in brain function and blood flow</a>, and signs of reduced brain inflammation.</p>
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Read more:
<a href="https://theconversation.com/six-things-you-can-do-to-reduce-your-risk-of-dementia-93061">Six things you can do to reduce your risk of dementia</a>
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<p><strong>Red and purple sweet potato</strong></p>
<p>Longevity has been associated with a small number of traditional diets, and one of these is the diet of the Okinawan people of Japan. The starchy staple of their diet is the purple sweet potato – rich in anthocyanin antioxidants. </p>
<p>Studies in mice have shown this potato’s anthocyanins protect against the effects of obesity on blood sugar regulation and cognitive function, <a href="https://www.ncbi.nlm.nih.gov/pubmed/29344660">and can reduce obesity-induced brain inflammation</a>.</p>
<p><strong>Green vegetables and herbs</strong></p>
<p>The <a href="https://www.ncbi.nlm.nih.gov/pubmed/29555333">traditional Mediterranean diet</a> has also been studied for its links to longevity and lower risk of Alzheimer’s disease. </p>
<p>Green vegetables and herbs feature prominently in this diet. They are rich sources of antioxidants including vitamins A and C, folate, polyphenols such as apigenin, and the carotenoid xanthophylls (especially if raw). A carotenoid is an orange or red pigment commonly found in carrots.</p>
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<img alt="" src="https://images.theconversation.com/files/285273/original/file-20190723-110154-135q3i2.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/285273/original/file-20190723-110154-135q3i2.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=401&fit=crop&dpr=1 600w, https://images.theconversation.com/files/285273/original/file-20190723-110154-135q3i2.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=401&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/285273/original/file-20190723-110154-135q3i2.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=401&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/285273/original/file-20190723-110154-135q3i2.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/285273/original/file-20190723-110154-135q3i2.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/285273/original/file-20190723-110154-135q3i2.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">
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<span class="caption">Green vegetables and herbs provide us with several types of antioxidants.</span>
<span class="attribution"><span class="source">From shutterstock.com</span></span>
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<p>The antioxidants and anti-inflammatory chemicals in the vegetables are believed to be responsible for <a href="https://www.annualreviews.org/doi/full/10.1146/annurev-food-030216-030125">slowing Alzheimer’s pathology development</a>, the build up of specific proteins which are toxic to brain cells.</p>
<p>Parsley is rich in apigenin, a powerful antioxidant. It readily crosses the barrier between the blood and the brain (unlike many drugs), <a href="https://www.ncbi.nlm.nih.gov/pubmed/28237914">where it reduces inflammation and oxidative stress</a>, and helps <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6304859/">brain tissue recovery</a> after injury. </p>
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<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/what-is-the-mediterranean-diet-and-why-is-it-good-for-you-12656">What is the Mediterranean diet and why is it good for you?</a>
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<p><strong>Beetroot</strong></p>
<p>Beetroot is a rich source of folate and polyphenol antioxidants, as well as copper and manganese. In particular, beetroot is <a href="https://www.tandfonline.com/doi/abs/10.3109/10715762.2011.641157">rich in betalain pigments</a>, which reduce oxidative stress and have anti-inflammatory properties.</p>
<p>Due to its nitrate content, beetroot can also boost the body’s nitric oxide levels. Nitric oxide relaxes blood vessels resulting in lowered blood pressure, a benefit which has <a href="https://www.ncbi.nlm.nih.gov/pubmed/30400267">been associated</a> with drinking beetroot juice.</p>
<p>A <a href="https://www.ncbi.nlm.nih.gov/pubmed/29077028">recent review of clinical studies</a> in older adults also indicated clear benefits of nitrate-rich beetroot juice on the health of our hearts and blood vessels.</p>
<h2>Foods to reduce</h2>
<p>Equally as important as adding good sources of antioxidants to your diet is minimising foods that are unhealthy: some foods contain damaged fats and proteins, which are major sources of oxidative stress and inflammation. </p>
<p>A high intake of “junk foods” including sweets, soft drinks, refined carbohydrates, processed meats and deep fried foods <a href="https://onlinelibrary.wiley.com/doi/full/10.1038/oby.2001.122">has been linked</a> to obesity, type 2 diabetes and cardiovascular disease.</p>
<p>Where these conditions are <a href="https://www.ncbi.nlm.nih.gov/pubmed/31062323">are all risk factors</a> for cognitive decline and Alzheimer’s disease, they should be kept to a minimum to reduce health risks and improve longevity.</p>
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<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/health-check-can-eating-certain-foods-make-you-smarter-113551">Health Check: can eating certain foods make you smarter?</a>
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<img src="https://counter.theconversation.com/content/117096/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Ralph Martins receives funding from the NHMRC, Edith Cowan University, Macquarie University, Australian Alzheimer's Research Foundation and the Lion's Alzheimer's Foundation.</span></em></p>Many chronic diseases increase our risk of Alzheimer’s disease. This link between our bodies and our brains means certain healthy choices could protect our cognitive function.Ralph N. Martins, Chair in Ageing and Alzheimer’s Disease, Edith Cowan University; Professor, Department of Biomedical Sciences, Macquarie UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/371702015-10-12T03:51:41Z2015-10-12T03:51:41ZHealth Check: seven nutrients important for mental health – and where to find them<figure><img src="https://images.theconversation.com/files/98007/original/image-20151012-23288-t3ve32.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">While nutrient supplementation can have a role in treating certain psychiatric disorders, all kinds of nutrients should, in the first instance, be consumed as part of a balanced wholefood diet.</span> <span class="attribution"><a class="source" href="https://www.flickr.com/photos/nakrnsm/3815441846/">PROPatrick Feller/Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span></figcaption></figure><p>Dietary nutrients are critical for brain structure and function, so they have a potentially profound impact on mental health. An increasingly <a href="http://www.thelancet.com/journals/lanpsy/article/PIIS2215-0366(14)00051-0/abstract">robust body of research</a> points to the detrimental effect of unhealthy diets and nutrient deficiencies, and to the protective value of healthy diets – along with select nutritional supplements as required – for maintaining and promoting mental health. </p>
<p>Research literature suggests dietary improvement and nutritional interventions may help reduce the risk, or even arrest the progression, of certain psychiatric disorders. <a href="http://www.thelancet.com/journals/lanpsy/article/PIIS2215-0366(14)00051-0/abstract">Clinical studies</a> support the use of certain nutrients, which influence a range of neurochemical activities beneficial for treating mental disorders, as medicinal supplements.</p>
<p>Evidence from clinical research supports the use of several nutritional medicines for certain psychiatric disorders: omega-3 fatty acids; N-acetyl cysteine (NAC); S-adenosyl methionine (SAMe); zinc; magnesium; vitamin D; and B vitamins (including folic acid). Other natural compounds such as amino acids, plant-based antioxidants and microbiotics (derived from fermented food or laboratory synthesis) are also known to influence brain health. </p>
<p>But while some evidence supports these natural compounds as having brain chemical-modulating effects, or having a role in treating certain mental disorders, we cannot currently name particular foods as being effective for the treatment of mental illness. The best nutritional advice at this point is to cultivate an unprocessed wholefood diet, with judicious prescriptive use of nutrients (if required) based on advice from a qualified health professional. </p>
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<img alt="" src="https://images.theconversation.com/files/98010/original/image-20151012-23309-1jxpwuh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/98010/original/image-20151012-23309-1jxpwuh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=353&fit=crop&dpr=1 600w, https://images.theconversation.com/files/98010/original/image-20151012-23309-1jxpwuh.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=353&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/98010/original/image-20151012-23309-1jxpwuh.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=353&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/98010/original/image-20151012-23309-1jxpwuh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=444&fit=crop&dpr=1 754w, https://images.theconversation.com/files/98010/original/image-20151012-23309-1jxpwuh.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=444&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/98010/original/image-20151012-23309-1jxpwuh.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=444&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="caption">Oily fish such as sardines are the best source of omega-3 fats.</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/jmenj/9434507959/">Jeanne Menj/Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
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<p>In the meanwhile, here are seven key nutrients that may positively influence brain health, and the foods they appear in.</p>
<p><strong>1. Omega-3</strong> </p>
<p>Polyunsaturated fats (in particular omega-3 fatty acids) <a href="http://www.ncbi.nlm.nih.gov/pubmed/23538073">have a vital role</a> in maintaining proper neuronal structure and function, as well as in modulating critical aspects of the inflammatory pathway in the body. Taking omega-3 supplements appears beneficial for addressing symptoms of depression, bipolar depression and post-traumatic stress disorder. And it may potentially help <a href="http://www.ncbi.nlm.nih.gov/pubmed/20124114">prevent psychosis</a>.</p>
<p>Omega-3 fats can be found in nuts, seeds and oysters, although the highest amounts exist in oily fish such as sardines, salmon (especially King salmon), anchovies and mackerel. Due to higher levels of mercury, larger fish, such as mackerel, should be consumed in moderation.</p>
<p><strong>2. B vitamins and folate</strong></p>
<p>We need B vitamins for a range of cellular and metabolic processes, and they have a critical role in the production of a range of brain chemicals. Folate (B9) deficiency <a href="http://www.psychiatrist.com/JCP/article/Pages/2009/v70s05/v70s0503.aspx">has been reported</a> in depressed populations and among people who respond poorly to antidepressants.</p>
<p>Several studies have assessed the antidepressant effect of folic acid (the synthetic form of folate) with antidepressant medication. <a href="http://www.psychiatrist.com/JCP/article/Pages/2009/v70s05/v70s0503.aspx">Some show positive results</a> in enhancing either antidepressant response rates or the onset of response to these medications. </p>
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<img alt="" src="https://images.theconversation.com/files/98012/original/image-20151012-23319-13i4uq6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/98012/original/image-20151012-23319-13i4uq6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/98012/original/image-20151012-23319-13i4uq6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/98012/original/image-20151012-23319-13i4uq6.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/98012/original/image-20151012-23319-13i4uq6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/98012/original/image-20151012-23319-13i4uq6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/98012/original/image-20151012-23319-13i4uq6.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">
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<span class="caption">Nuts are a good source of folate, amino acids and minerals.</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/addiction/62824084/">Ahmed Al Masaood/Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by-nc-nd/4.0/">CC BY-NC-ND</a></span>
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<p>Folate is found in abundance in leafy green vegetables, legumes, whole grains, brewer’s yeast and nuts. Unprocessed meats, eggs, cheese, dairy, whole grains and nuts are, in general, richest in B vitamins. If you’re going to take supplements, it’s advisable to take B vitamins together as <a href="http://www.ncbi.nlm.nih.gov/pubmed/23253391">they have a synergistic effect</a>.</p>
<p><strong>3. Amino acids</strong></p>
<p>Amino acids are the building blocks for creating proteins, from which brain circuitry and brain chemicals are formed. Some amino acids are precursors of mood-modulating chemicals; tryptophan, for instance, is needed to create serotonin. Another example is cysteine, a sulphur-based amino acid that can convert into glutathione – the body’s most powerful antioxidant. </p>
<p>When given as a supplement, an amino acid form known as N-acetyl cysteine (NAC) converts into <a href="https://en.wikipedia.org/wiki/Glutathione">glutathione</a> in the body. We have <a href="http://www.ncbi.nlm.nih.gov/pubmed/23369637">evidence that it’s helpful</a> in bipolar depression, schizophrenia, trichotillomania and other compulsive and addictive behaviours. Another amino acid-based nutrient known as S-adenosyl methionine (SAMe) <a href="http://www.ncbi.nlm.nih.gov/pubmed/24856557">has antidepressant qualities</a>. </p>
<p>Amino acids are found in any source of protein, most notably meats, seafood, eggs, nuts and legumes.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/98013/original/image-20151012-23319-wauedl.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/98013/original/image-20151012-23319-wauedl.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=398&fit=crop&dpr=1 600w, https://images.theconversation.com/files/98013/original/image-20151012-23319-wauedl.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=398&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/98013/original/image-20151012-23319-wauedl.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=398&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/98013/original/image-20151012-23319-wauedl.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=500&fit=crop&dpr=1 754w, https://images.theconversation.com/files/98013/original/image-20151012-23319-wauedl.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=500&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/98013/original/image-20151012-23319-wauedl.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=500&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Amino acids are found in sources of protein such as meat.</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/wurzeltod/357151207/">Suzanne Gerber/Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by-nc/4.0/">CC BY-NC</a></span>
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<p><strong>4. Minerals</strong> </p>
<p>Minerals, especially zinc, magnesium and iron, have important roles in neurological function. </p>
<p>Zinc is an abundant trace element, being involved in many brain chemistry reactions. It’s also a key element supporting proper immune function. <a href="http://www.ncbi.nlm.nih.gov/pubmed/25012438">Deficiency has been linked</a> to increased depressive symptoms and there’s emerging evidence for zinc supplementation in <a href="http://www.ncbi.nlm.nih.gov/pubmed/21798601">improving depressed mood</a>, primarily alongside antidepressants. </p>
<p>Magnesium is also involved in many brain chemistry reactions and <a href="http://www.ncbi.nlm.nih.gov/pubmed/19085527">deficiency has been linked</a> to depressive and anxiety symptoms. Iron is involved in many neurological activities and <a href="http://www.biomedcentral.com/1471-244X/13/161">deficiency is associated with</a> anxiety and depressive symptoms as well as developmental problems. This is, in part, due to its role in transporting oxygen to the brain.</p>
<p>Zinc is abundant in lean meats, oysters, whole grains, pumpkin seeds and nuts, while magnesium is richest in nuts, legumes, whole grains, leafy greens and soy. Iron occurs in higher amounts in unprocessed meats and organ meats, such as liver, and in modest amounts in grains, nuts and leafy greens, such as spinach. </p>
<p><strong>5. Vitamin D</strong></p>
<p>Vitamin D is a fat-soluble compound that’s important as much for brain development as it is for bone development. Data suggests low maternal levels of vitamin D are <a href="http://www.ncbi.nlm.nih.gov/pubmed/22796576">implicated in schizophrenia risk</a>, and deficiency is linked to <a href="http://www.ncbi.nlm.nih.gov/pubmed/23377209">increased depressive symptoms</a>. But there’s little evidence to support the use of <a href="http://www.ncbi.nlm.nih.gov/pubmed/24423304">vitamin D supplements for preventing depression</a>.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/98015/original/image-20151012-23300-uz3k8j.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/98015/original/image-20151012-23300-uz3k8j.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=362&fit=crop&dpr=1 600w, https://images.theconversation.com/files/98015/original/image-20151012-23300-uz3k8j.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=362&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/98015/original/image-20151012-23300-uz3k8j.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=362&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/98015/original/image-20151012-23300-uz3k8j.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=456&fit=crop&dpr=1 754w, https://images.theconversation.com/files/98015/original/image-20151012-23300-uz3k8j.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=456&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/98015/original/image-20151012-23300-uz3k8j.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=456&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Vitamin D can be synthesised via sunlight.</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/naturesdawn/4299041739/">Dawn Ellner/Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
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<p>Vitamin D can be synthesised via sunlight: 15 minutes a day on the skin between 10am and 3pm during summer, although be sure to seek professional health advice regarding skin cancer concerns. Aside from sunlight, vitamin D can also be found in oily fish, UVB-exposed mushrooms and fortified milk.</p>
<p><strong>6. Plant-based antioxidants</strong></p>
<p>An increase in oxidative stress and damage to brain cells has been <a href="http://www.ncbi.nlm.nih.gov/pubmed/22271002">implicated in a range of mental disorders</a>, including depression and dementia. Antioxidant compounds (such as “polyphenols”, which are found in fruits and certain herbs) may “mop up” free radicals that damage cells to <a href="http://www.ncbi.nlm.nih.gov/pubmed/22334236">provide a natural way</a> to combat excessive oxidation.</p>
<p>Consuming natural antioxidant compounds through your diet is better than taking supplements of high doses of synthetic vitamin A, C or E, as the oxidative system is finely tuned and excess may actually be harmful. </p>
<p>Fruits and vegetables contain these antioxidant compounds in relative abundance, especially blackberries, blueberries, raspberries and goji berries; grapes; mangoes and mangosteen; onions; garlic; kale; as well as green and black tea; various herbal teas; and coffee.</p>
<p><strong>7. Microbiotics</strong></p>
<p><a href="http://www.ncbi.nlm.nih.gov/pubmed/23384445">Research</a> shows a connection between the bacteria in our guts and brain health, which may affect mental health. When the composition of the gut microbiota is less than optimal, it can result in inflammatory responses that <a href="http://www.ncbi.nlm.nih.gov/pubmed/21135322">may negatively affect</a> the nervous system and brain function. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/98009/original/image-20151012-23283-125i0an.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/98009/original/image-20151012-23283-125i0an.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/98009/original/image-20151012-23283-125i0an.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/98009/original/image-20151012-23283-125i0an.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/98009/original/image-20151012-23283-125i0an.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=502&fit=crop&dpr=1 754w, https://images.theconversation.com/files/98009/original/image-20151012-23283-125i0an.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=502&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/98009/original/image-20151012-23283-125i0an.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=502&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Diets high in sugary, fatty and processed foods are associated with depression and poor brain health.</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/brizzlebornandbred/9375507295/">Paul Townsend/Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>A balanced microfloral environment is supported by a diet rich in the foods that nourish beneficial bacteria and reduce harmful microbial species, such as <em>Helicobacter pylori</em>. Beneficial microflora can be supported by eating fermented foods such as tempeh, sauerkraut, kefir and yoghurt, and also by pectin-rich foods such as fruit skin. </p>
<h2>What now?</h2>
<p>Diets high in sugary, fatty and processed foods <a href="https://theconversation.com/you-are-what-you-eat-how-diet-affects-mental-well-being-27115">are associated</a> with depression and poor brain health. While nutrient supplementation can have a role in maintaining proper brain function and treating certain psychiatric disorders, nutrients should, in the first instance, be consumed as part of a balanced wholefood diet.</p>
<p>There is now enough research evidence to show the importance of nutrients for mental as well as physical well-being. A <a href="http://www.thelancet.com/journals/lanpsy/article/PIIS2215-0366(14)00051-0/abstract">discussion about diet and nutrition</a> should be the starting point in conversations about mental health, just as it is for physical health.</p>
<p><em>If you’re interested in participating in a clinical trial prescribing nutrients for treating depression (SE Queensland and Victoria only), visit <a href="http://nutrientsdepressionstudy.com/">nutrientsdepressionstudy</a>.</em> </p>
<p><strong>Acknowledgement</strong>: Dr Drew Ramsey contributed to this article.</p><img src="https://counter.theconversation.com/content/37170/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Jerome Sarris has received funding from Integria Health, Blackmores, Bioceuticals, Pepsico, HealthEd, Soho-Flordis, Pfizer, Elsevier, the Society for Medicinal Plant and Natural Product Research, CR Roper Fellowship, and The National Health and Medical Research Council. He is affiliated with The International Society for Nutritional Psychiatry Research. </span></em></p>A growing body of research points to the detrimental effect of unhealthy diets and the protective value of healthy diets – along with select nutritional supplements as required – for maintaining and promoting mental health.Jerome Sarris, Senior Research Fellow, The University of MelbourneLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/29992011-11-03T19:35:57Z2011-11-03T19:35:57ZOld made new: medication offers hope for bipolar depression<figure><img src="https://images.theconversation.com/files/4853/original/5092133032_17efe2a99e_b.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Current treatments for bipolar disorder are more effective for the symptoms of mania than for depression.</span> <span class="attribution"><span class="source">Chris Connelly</span></span></figcaption></figure><p>Little understood and lacking effective drugs for addressing the scope of its symptoms, bipolar disorder can wreak havoc with the lives of people who suffer from it. </p>
<p>Now an over-the-counter drug is offering hope for treating the sometimes deadly depressive stage of this disorder. </p>
<p>Bipolar disorder affects approximately 1% to 2% of the population and is characterized by two illness phases – mania and depression. </p>
<p>The symptoms of mania include increased energy, decreased sleep, enhanced impulsivity and elevated mood while the symptoms of depression include decreased mood and energy, altered sleep patterns, suicidal thoughts and a lack of motivation. </p>
<p>People with bipolar disorder tend to spend more time in the depressive phase than the manic phase. And suicide, the most catastrophic consequence of the disorder, is more of a risk during depression. </p>
<p>Current treatments for bipolar disorder are more effective for the symptoms of mania than for depression. </p>
<p>What’s more, standard medications used to treat unipolar (clinical) depression aren’t as effective for treating the depressive phase of bipolar disorder (commonly known as bipolar depression). </p>
<h2>Little known</h2>
<p>We don’t know the precise mechanisms that lead to bipolar disorder but there’s consensus among the research community that it involves complex interactions of many factors. </p>
<p>One of the few things we do know is that people with bipolar disorder have increased oxidative stress.</p>
<p>Oxidative stress is a state in which the brain’s capacity to defend against free radicals is overwhelmed, leading to cell damage and adverse changes in the way cells function. </p>
<p>Examples of oxidation in action are rusting iron, or when your apple turns brown once you’ve bitten it. The brown part of the apple is damaged by oxidative stress.</p>
<p>During normal brain function, free radicals are produced and have healthy functions in the brain’s biological systems. The balance between oxidative stress and oxidative defences is maintained by antioxidants. </p>
<p>It is only when the levels of free radicals exceed the levels of antioxidants that oxidative stress occurs. This may occur both through increased oxidative stress or a decrease in antioxidant capacity.</p>
<p>It appears that both of these factors are present in bipolar disorder.</p>
<h2>A promising find</h2>
<p>Cysteine is an essential amino acid required for many biological functions. It’s the critical component of the brain’s primary antioxidant, glutathione. </p>
<p>N-acetyl cysteine (NAC) – a registered medicine currently used to treat paracetamol overdose and as a mucolytic (breaks down phlegm) in cystic fibrosis – is a modified version of this naturally occurring amino acid. </p>
<p>Having previously shown that NAC reduces the core symptoms of bipolar disorder and schizophrenia, our research team is now studying NAC for the treatment of unipolar (clinical) depression and autism.</p>
<p>In our <a href="http://www.ncbi.nlm.nih.gov/pubmed?term=berk%20open%20label%20acetyl%20cysteine">latest study</a>, we investigated the potential benefits of N-acetyl cysteine as an adjunctive (or add-on) treatment for bipolar depression.</p>
<p>Given the increased oxidative stress in bipolar disorder, we studied NAC to see if increasing the levels of the primary antioxidant in the brain (glutathione) could improve the symptoms experienced by those with the disorder. (Remember that people with bipolar disorder have decreased defenses against oxidative stress.)</p>
<p>The study involved 149 people (aged between 22 and 70 years) with bipolar depression who were recruited across several sites including Melbourne, Geelong, Sydney and Brazil. </p>
<p>All of the participants in the study received 2 grams of NAC a day for two months, in addition to any medication they were already taking. </p>
<p>This “add-on” design is more attractive to participants as they can continue with their current treatment. It also more closely reflects reality, as people with bipolar disorder are often given combinations of treatments.</p>
<p>We found that participants’ depressive symptoms decreased significantly over the two-month period. And overall, participants reported improved functioning (such as increased rates of work or better social interactions) and quality of life. </p>
<p>This suggests NAC may be effective as an add-on therapy for the treatment of bipolar disorder. </p>
<p>And unlike what happens in many clinical trials, NAC was available for purchase at the end of the study. N-acetyl cysteine can be purchased from a limited number of pharmacies in Australia and is also available from online sources. </p>
<p>Further studies are required to fully explore the potential of NAC as a treatment for bipolar depression even though these results are promising. </p>
<p>The impact of bipolar disorder can be significant and while current therapies are useful, many people either don’t respond or tolerate treatment. </p>
<p>Studies such as these provide hope for newer and safer therapies that may lead to better outcomes for people with the disorder.</p><img src="https://counter.theconversation.com/content/2999/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Olivia Dean receives funding from the NHMRC, Servier, The Stanley Medical Research Institute, Australian Rotary Heatlh and the Marian and E.H. Flack Trust. She is employed by the Mental Health Research Institute and hold adjunct appointments with Deakin University and the University of Melbourne.</span></em></p>Little understood and lacking effective drugs for addressing the scope of its symptoms, bipolar disorder can wreak havoc with the lives of people who suffer from it. Now an over-the-counter drug is offering…Olivia Dean, Alfred Deakin Postdoctoral Research Fellow, Deakin UniversityLicensed as Creative Commons – attribution, no derivatives.