tag:theconversation.com,2011:/au/topics/aspartame-5200/articlesAspartame – The Conversation2023-07-21T12:26:43Ztag:theconversation.com,2011:article/2099572023-07-21T12:26:43Z2023-07-21T12:26:43ZWHO expert cancer group states that the sweetener aspartame is a possible carcinogen, but evidence is limited – 6 questions answered<figure><img src="https://images.theconversation.com/files/538137/original/file-20230718-27-wh515o.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C3866%2C2590&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Research on possible links between aspartame consumption and cancer is ongoing and far from conclusive.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/coffee-royalty-free-image/95061040?phrase=artificial%2Bsweetener">celsopupo/iStock via Getty Images Plus</a></span></figcaption></figure><p><em>The World Health Organization declared on July 14, 2023, that the widely used synthetic sweetener <a href="https://www.who.int/news/item/14-07-2023-aspartame-hazard-and-risk-assessment-results-released">aspartame could be a “possible” carcinogen</a>, or cancer-causing agent, on the basis of “limited evidence for cancer in humans.”</em> </p>
<p><em>But the agency also concluded that the currently available data does not warrant a change of the acceptable daily intake of aspartame at this time.</em></p>
<p><em>The Conversation asked chronic disease epidemiologist <a href="http://gsm.utmck.edu/internalmed/faculty/terry.cfm">Paul D. Terry</a>, public health scholar <a href="https://publichealth.utk.edu/people/jchen/">Jiangang Chen</a> and nutrition expert <a href="https://nutrition.utk.edu/people/ling-zhao/">Ling Zhao</a>, all from the University of Tennessee, to put these seemingly contradictory findings into perspective based on the available scientific evidence.</em></p>
<h2>1. Why is aspartame being classified as ‘possibly’ cancer-causing?</h2>
<p>Aspartame is an artificial sweetener that is added to many foods, candies, gums and beverages, such as diet soda. Because it is approximately <a href="https://www.fda.gov/food/food-additives-petitions/aspartame-and-other-sweeteners-food">200 times sweeter than table sugar</a>, smaller amounts of aspartame are added to foods, and they contribute considerably fewer calories. NutraSweet and Equal are well-known brand names for aspartame sold in packages for individual use. </p>
<p>The <a href="https://www.iarc.who.int/cards_page/about-iarc/">International Agency for Research on Cancer</a>, an entity within the WHO, evaluated findings from both human and animal studies of aspartame and cancer. The group noted some positive associations between <a href="https://www.who.int/news/item/14-07-2023-aspartame-hazard-and-risk-assessment-results-released">aspartame consumption and hepatocellular carcinoma</a>, a form of liver cancer. </p>
<p>This WHO group classifies degrees of evidence that an agent has cancer-causing potential as being “sufficient,” “limited,” “inadequate” or “suggesting lack of carcinogenicity.” “Limited” evidence, as it pertains to the WHO’s new announcement on aspartame, means that although there is some evidence for an association, that evidence cannot be considered “sufficient” to infer a causal relationship.</p>
<p>Ultimately, the group concluded that several limiting factors could possibly explain the positive associations in those studies. These include the small number of human studies available, the complexity of studying people’s dietary behaviors and possible bias from factors such as higher-risk people – for example, those with diabetes – selecting diet products more often and ingesting higher quantities of aspartame than the average consumer. Therefore, the classification of “limited evidence” implies the need for additional studies.</p>
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<figcaption><span class="caption">Aspartame is found in many products: diet soda, ice cream, cereals, toothpaste and even some medications.</span></figcaption>
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<h2>2. What are the current guidelines for aspartame consumption?</h2>
<p>The Food and Agriculture Organization’s <a href="https://www.fao.org/food-safety/scientific-advice/jecfa/en/#">Joint Expert Committee on Food Additives</a>, an international committee of science experts that is operated by both the WHO and the United Nations, currently <a href="https://www.who.int/news/item/14-07-2023-aspartame-hazard-and-risk-assessment-results-released#">recommends a daily maximum</a> of 40 milligrams per kilogram of body weight for aspartame.</p>
<p>This amount of aspartame per day translates to approximately eight to 12 cans of soda, or approximately 60 packets of aspartame, for a person weighing 132 pounds (60 kilograms). For a child weighing 33 pounds (15 kg), it translates to between two to three cans of aspartame-sweetened soda per day, or approximately 15 packets of aspartame. Some individuals may consume more aspartame than this, but such high intake is not typical. </p>
<h2>3. Does the WHO’s new stance change that recommendation?</h2>
<p>Independently of the expert panel on cancer, the food safety group also evaluated the available evidence and concluded that there was no “convincing evidence” from either animal or human studies that aspartame consumption causes adverse effects within the currently established daily limits. </p>
<p>Based on assessments of the findings of both groups, the director of the Department of Nutrition and Food Safety of the WHO stated that, “while safety is not a major concern” at the doses in which aspartame are commonly used, “potential effects have been described that need to be investigated by more and better studies.” The American Cancer Society has also stated that it <a href="https://www.cancer.org/cancer/risk-prevention/chemicals/aspartame.html">supports further research into possible health concerns</a> related to aspartame.</p>
<p>It is important to note that people with the rare inherited disorder called <a href="https://my.clevelandclinic.org/health/diseases/17816-phenylketonuria">phenylketonuria</a>, or PKU, should <a href="https://www.fda.gov/food/food-additives-petitions/aspartame-and-other-sweeteners-food">avoid or restrict aspartame intake</a>. </p>
<h2>4. How can two consensus groups reach different conclusions?</h2>
<p>It is not uncommon for scientific consensus groups to differ in how they classify risk based on the results of published studies, even if more than one of those consensus groups is affiliated with the same agency or parent organization. </p>
<p>Whereas the WHO’s expert cancer group’s stance may appear to be more worrisome than that of the committee on food safety, in fact, the latter’s “no convincing evidence” is consistent with the cancer group’s “limited evidence” classification. Because, unlike the cancer group, the food safety committee considers risk of aspartame at specific consumption levels, the WHO as a whole continues to support the food safety committee’s existing recommendations for allowable daily aspartame intake of up to 40 milligrams per kilogram of body weight. </p>
<p>Of note, the committee’s recommended maximum daily intake is still more conservative than the current U.S. Food and Drug Administration’s <a href="https://www.cancer.org/cancer/risk-prevention/chemicals/aspartame.html">recommended maximum daily allowance</a> of 50 milligrams of aspartame per kilogram of body weight.</p>
<h2>5. How does aspartame compare to other sweeteners?</h2>
<p>Alternatives to aspartame include other <a href="https://theconversation.com/whats-the-difference-between-sugar-other-natural-sweeteners-and-artificial-sweeteners-a-food-chemist-explains-sweet-science-172571">artificial sweeteners</a> such as saccharin and sucralose, sugar alcohols like sorbitol and xylitol, naturally derived sugar-free sweeteners like Stevia and simple sugars, such as those in sugar cane, sugar beets and honey. </p>
<p>But, like aspartame, many of these sweeteners have been implicated in developing cancer. This list includes <a href="https://doi.org/10.1371/journal.pmed.1003950">acesulfame potassium, or Ace-K</a> – a synthetic calorie-free sugar substitute – as well as <a href="https://www.upstate.edu/news/articles/2023/2023-03-25-perl.php">sugar alcohols</a> and even <a href="https://doi.org/10.3390%2Fcancers14246042">simple sugar</a>. </p>
<p>The availability of a wide variety of approved sweeteners seems like a good thing, but studying the many possible risks associated with sweeteners is challenging, since <a href="https://www.science.org/content/blog-post/sugar-substitutes-surprise">people have complex diets and lifestyles</a>. </p>
<h2>6. So what should consumers do?</h2>
<p>For now, as is the case with aspartame, these sweeteners remain approved for human use because there isn’t sufficient evidence to support an association with cancer. And, <a href="https://www.mayoclinic.org/healthy-lifestyle/nutrition-and-healthy-eating/in-depth/artificial-sweeteners/art-20046936">as noted by the Mayo Clinic</a>, artificial sweeteners may play a beneficial role for some people who are <a href="https://doi.org/10.1016/j.eprac.2021.06.013">seeking to manage their weight</a> or control their sugar intake. Studies show that sugar <a href="https://doi.org/10.1136/bjsports-2017-097971">may be addictive for some individuals</a>.</p>
<p>When making a decision about consumption of sweeteners, consumers should consider factors like taste preference, body weight and composition, diabetes status and risk, possible allergic responses and the evidence that may result from ongoing and future studies. In certain cases, such as with individuals who have or are at future risk of diabetes, people should talk with their physician or other health care provider to determine the best choice. </p>
<p>One thing is clear: Scientific studies on aspartame consumption will continue, and it will be important for both consumers and the research community to continue weighing potential risks.</p><img src="https://counter.theconversation.com/content/209957/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 organization that would benefit from this article, and have disclosed no relevant affiliations beyond their academic appointment.</span></em></p>An expert panel found a potential association with liver cancer, but too little research exists to assume a causal connection. For now, the WHO left current consumption guidelines unchanged.Paul D. Terry, Professor of Epidemiology, University of TennesseeJiangang Chen, Associate Professor of Public Health, University of TennesseeLing Zhao, Professor of Nutrition, University of TennesseeLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2088442023-07-14T01:24:43Z2023-07-14T01:24:43ZDoes artificial sweetener aspartame really cause cancer? What the WHO listing means for your diet soft drink habit<figure><img src="https://images.theconversation.com/files/536737/original/file-20230711-23-sl30n6.jpg?ixlib=rb-1.1.0&rect=4%2C0%2C3240%2C2155&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Shutterstock</span></span></figcaption></figure><p>The International Agency for Research on Cancer (IARC), which is the specialised cancer agency of the World Health Organization, has declared aspartame may be a <a href="https://www.who.int/news/item/14-07-2023-aspartame-hazard-and-risk-assessment-results-released">possible carcinogenic hazard to humans</a>. </p>
<p>Another branch of the WHO, the Joint WHO and Food and Agriculture Organization’s Expert Committee on Food Additives has assessed the risk and developed recommendations on how much aspartame is safe to consume. They have recommended the acceptable daily intake be 0 to 40mg per kilo of body weight, as we currently have <a href="https://www.foodstandards.gov.au/consumer/additives/aspartame/Pages/default.aspx">in Australia</a>.</p>
<p>A hazard is different to a risk. The hazard rating means it’s an agent that is capable of causing cancer; a risk measures the likelihood it could cause cancer.</p>
<p>So what does this hazard assessment mean for you?</p>
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<h2>Firstly, what is aspartame?</h2>
<p><a href="https://www.foodstandards.gov.au/consumer/additives/aspartame/Pages/default.aspx">Aspartame is an artificial sweetener</a> that is 200 times sweeter than sugar, but without any kilojoules. </p>
<p>It’s used in a <a href="https://www.foodstandards.gov.au/consumer/additives/aspartame/Pages/default.aspx">variety of products</a> including carbonated drinks such as Coke Zero, Diet Coke, Pepsi Max and some home brand offerings. You can identify aspartame in drinks and foods by looking for additive number 951. </p>
<p>Food products such as yogurt and confectionery may also contain aspartame, but it’s not stable at warm temperatures and thus not used in baked goods. </p>
<p>Commercial names of aspartame include Equal, Nutrasweet, Canderel and Sugar Twin. In Australia the acceptable daily intake is 40mg per kilo of body weight per day, which is about 60 sachets.</p>
<p><a href="https://www.fda.gov/food/food-additives-petitions/aspartame-and-other-sweeteners-food#:%7E:text=How%20many%20packets%20can%20a,based%20on%20its%20sweetness%20intensity%3F&text=Notes%20About%20the%20Chart%3A,50%20mg%2Fkg%20bw%2Fd">In America</a> the acceptable daily intake has been set at 75 sachets. </p>
<h2>What evidence have they used to come to this conclusion?</h2>
<p><a href="https://www.who.int/news/item/14-07-2023-aspartame-hazard-and-risk-assessment-results-released">IARC looked closely</a> at the <a href="https://cdn.who.int/media/docs/default-source/nutrition-and-food-safety/july-13-final-summary-of-findings-aspartame.pdf?sfvrsn=a531e2c1_5&download=true">evidence base</a> from around the world – using data from observational studies, experimental studies and animal studies. </p>
<p>They found there was some limited evidence in human studies linking aspartame and cancer (specifically liver cancer) and limited evidence from animal studies as well. </p>
<p>They also considered the biological mechanism studies which showed how cancer may develop from the consumption of aspartame. Usually these are lab-based studies which show exactly how exposure to the agent may lead to a cancer. In this case they found there was limited evidence for how aspartame might cause cancer.</p>
<p>There were only three human studies that looked at cancer and aspartame intake. These large observational studies used the intake of soft drinks as an indicator of aspartame intake. </p>
<p>All three found a positive association between artificially sweetened beverages and liver cancer in either all of the population they were studying or sub-groups within them. But these studies could not rule out other factors that may have been responsible for the findings. </p>
<p>A study <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6284800/">conducted in Europe</a> followed 475,000 people for 11 years and found that each additional serve of diet soft drink consumed per week was linked to a 6% increased risk of liver cancer. However the scientists did conclude that due to the rarity of liver cancer they still had small numbers of people in the study.</p>
<p><a href="https://pubmed.ncbi.nlm.nih.gov/35728406/">In a study from the US</a>, increased risk of liver cancer was seen in people with diabetes who drank more than two or more cans of a diet soda a week.</p>
<p>The <a href="https://aacrjournals.org/cebp/article/31/10/1907/709398/Sugar-and-Artificially-Sweetened-Beverages-and">third study</a>, also from the US, found an increase in liver cancer risk in men who never smoked and drank two or more artificially sweetened drinks a day. </p>
<p>From this they have decided to declare aspartame as a Group 2b “possible carcinogen”. But they have also said more and better research is needed to further understand the relationship between aspartame and cancer. </p>
<p>IARC has four categories (groupings) available for potential substances (or as they are referred to by IARC, “agents”) that may cause cancer.</p>
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<a href="https://images.theconversation.com/files/536738/original/file-20230711-26-ln4ks.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Cup of frothy soda" src="https://images.theconversation.com/files/536738/original/file-20230711-26-ln4ks.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/536738/original/file-20230711-26-ln4ks.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=401&fit=crop&dpr=1 600w, https://images.theconversation.com/files/536738/original/file-20230711-26-ln4ks.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=401&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/536738/original/file-20230711-26-ln4ks.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=401&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/536738/original/file-20230711-26-ln4ks.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/536738/original/file-20230711-26-ln4ks.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/536738/original/file-20230711-26-ln4ks.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">An Australian would have to consume unrealistic amounts of aspartame to reach the daily limit.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
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<h2>What does each grouping mean?</h2>
<p><strong>Group 1 Carcinogenic to humans:</strong> an agent in this group is carcinogenic, which means there is convincing evidence from human studies and we know precisely <em>how</em> it causes cancer. There are 126 agents in this group, including tobacco smoking, alcohol, processed meat, radiation and ionising radiation.</p>
<p><strong>Group 2a Probably carcinogenic to humans:</strong> there are positive associations between the agent and cancer in humans, but there may still be other explanations for the association which were not fully examined in the studies. There are 95 agents in this group, including red meat, DDT insecticide and night shift work.</p>
<p><strong>Group 2b Possibly carcinogenic in humans:</strong> this means limited evidence of causing cancer in humans, but sufficient evidence from animal studies, or the mechanism of how the agent may be carcinogenic is well understood. This basically means the current evidence indicates an agent may possibly be carcinogenic, but more scientific evidence from better conducted studies is needed. There are now <a href="https://monographs.iarc.who.int/agents-classified-by-the-iarc/">323</a> agents in this group, including aloe vera (whole leaf extract), ginkgo biloba and lead.</p>
<p><strong>Group 3 Not classifiable as a carcinogen:</strong> there’s not enough evidence from humans or animals, and there is limited mechanistic evidence of how it may be a carcinogen. There are 500 agents in this group.</p>
<h2>So do I have to give up my diet soft drink habit?</h2>
<p>For a 70kg person you would need to consume about 14 cans (over 5 litres) of soft drink sweetened with aspartame a day to reach the acceptable daily intake.</p>
<p>But we need to remember there may also be aspartame added in other foods consumed. So this is an unrealistic amount to consume, but not impossible. </p>
<p>We also need to consider all the evidence on aspartame together. The foods we typically see aspartame in are processed or ultra-processed, which have recently also been <a href="https://theconversation.com/ultra-processed-foods-are-trashing-our-health-and-the-planet-180115">shown to be detrimental to health</a>.</p>
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Read more:
<a href="https://theconversation.com/ultra-processed-foods-are-trashing-our-health-and-the-planet-180115">Ultra-processed foods are trashing our health – and the planet</a>
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<p>And artificial sweeteners (including aspartame) <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2892765/#!po=59.3750">can make people crave more sugar</a>, making them want to eat more food, potentially causing them to gain more weight.</p>
<p>All together, this indicates we should be more careful about the amount of artificial sweeteners we consume, since they <a href="https://theconversation.com/the-who-says-we-shouldnt-bother-with-artificial-sweeteners-for-weight-loss-or-health-is-sugar-better-205827">do not provide any health benefits</a>, and have possible adverse effects. </p>
<p>But overall, from this evidence, drinking the occasional or even daily can of a diet drink is safe and probably not a cancer risk.</p>
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<p><em>Correction: this article originally stated each serve of soft drink in a study was linked to a 6% increased risk of liver cancer, however it was each additional serve per week. This has been amended.</em></p><img src="https://counter.theconversation.com/content/208844/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Evangeline Mantzioris is affiliated with Alliance for Research in Nutrition, Exercise and Activity (ARENA) at the University of South Australia. Evangeline Mantzioris has received funding from the National Health and Medical Research Council, and has been appointed to the National Health and Medical Research Council Dietary Guideline Expert Committee.</span></em></p>IARC has listed the artificial sweetener aspartame as possibly cancer causing. Here’s how to digest the findings.Evangeline Mantzioris, Program Director of Nutrition and Food Sciences, Accredited Practising Dietitian, University of South AustraliaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2088952023-07-04T15:11:40Z2023-07-04T15:11:40ZAspartame: popular sweetener could be classified as a possible carcinogen by WHO – but there’s no cause for panic<figure><img src="https://images.theconversation.com/files/535489/original/file-20230704-16-qfev1h.jpg?ixlib=rb-1.1.0&rect=8%2C0%2C5646%2C3764&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/double-cool-ice-soft-drink-cola-647315608">MMD Creative/Shutterstock</a></span></figcaption></figure><p>According to <a href="https://www.reuters.com/business/healthcare-pharmaceuticals/whos-cancer-research-agency-say-aspartame-sweetener-possible-carcinogen-sources-2023-06-29/">reports</a>, the International Agency for Research on Cancer (IARC), part of the World Health Organization (WHO), is set to declare the artificial sweetener aspartame as “possibly carcinogenic to humans”. </p>
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<p><a href="https://pubmed.ncbi.nlm.nih.gov/26377607/">Aspartame</a> is about <a href="https://www.sciencedirect.com/science/article/abs/pii/0308814685901190">200 times sweeter</a> than sugar and is one of the most commonly used artificial sweeteners. It’s used particularly in “low calorie” or “diet” foods and beverages, but is contained in a wide variety of products including drinks, ice creams, chewing gums, confectionery, sauces and snacks.</p>
<p>We don’t have further information yet on what evidence the IARC will base this new classification on, but the WHO will publish the full data <a href="https://monographs.iarc.who.int/wp-content/uploads/2023/06/Meeting134-QA-June2023.pdf">on July 14</a>. </p>
<p>While reports like these can understandably be worrying, there’s no reason to panic at this stage.</p>
<p>Aspartame was first approved for use by the US Food and Drug Administration (FDA) <a href="https://efsa.onlinelibrary.wiley.com/doi/epdf/10.2903/j.efsa.2013.3496">in 1974</a>, and ever since then there have been claims made about its potential effects on health. </p>
<p>Over time, aspartame has not only been linked to cancer, but also to <a href="https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0116212">other conditions</a> such as multiple sclerosis, blindness, seizures, memory loss, depression, anxiety, birth defects and death. </p>
<p>However, frequent evaluations by regulatory agencies such as the <a href="https://apps.who.int/food-additives-contaminants-jecfa-database/Home/Chemical/62">WHO</a>, the FDA and the <a href="https://www.efsa.europa.eu/en/efsajournal/pub/3496">European Food Safety Authority</a> (EFSA) have found no evidence to support these assertions.</p>
<p>So far, the regulators have all agreed that it’s safe for a person to consume <a href="https://www.efsa.europa.eu/en/efsajournal/pub/3496">40mg of aspartame</a> per kilogram of their body weight per day. That’s about 2.8g for a 70kg adult – and is much more than most people consume. </p>
<h2>What does ‘possibly carcinogenic’ actually mean?</h2>
<p>The safety of food additives is <a href="https://www.efsa.europa.eu/en/topics/topic/food-additive-re-evaluations">regularly reevaluated</a>. This is important as new evidence can emerge, especially with the development of different methods to assess the health effects of additives.</p>
<p>This year, aspartame has been reevaluated by two WHO agencies: the International Agency for Research on Cancer (<a href="https://www.iarc.who.int/">IARC</a>) and the Joint FAO/WHO Expert Committee on Food Additives (<a href="https://www.who.int/groups/joint-fao-who-expert-committee-on-food-additives-(jecfa)">JECFA</a>). </p>
<p>The two agencies have <a href="https://monographs.iarc.who.int/wp-content/uploads/2023/06/Meeting134-QA-June2023.pdf">very different remits</a>. The IARC looks at hazard and JECFA at risk. This distinction is important. For example, sunshine is a hazard as it can cause skin cancer, but the risk depends on the time spent in the sun and whether one uses sunscreen.</p>
<p>The IARC’s job is to investigate possible causes of cancer and identify hazards. In its <a href="https://monographs.iarc.who.int/">reports</a> (called monographs), it reviews all available evidence and classifies hazards into one of <a href="https://www.iarc.who.int/wp-content/uploads/2023/06/IARC_MONO_classification_2023_updated.png">four categories</a>: </p>
<ul>
<li>Group 1: carcinogenic to humans (sufficient evidence for cancer in humans)</li>
<li>Group 2a: probably carcinogenic to humans (limited evidence in humans, sufficient evidence in animals)</li>
<li>Group 2b: possibly carcinogenic to humans (limited evidence in humans, insufficient evidence in animals) </li>
<li>Group 3: not classifiable (inadequate evidence in humans or animals).</li>
</ul>
<p>Aspartame will reportedly be classified into group 2b. It shares this category with aloe vera leaves, electromagnetic radiation, the heart drug <a href="https://bnf.nice.org.uk/drugs/digoxin/">digoxin</a> and engine exhaust fumes, among <a href="https://www.bbc.com/future/article/20230630-aspartame-what-else-is-possibly-cancerous">many other things</a>. For all of these hazards, there is some limited data that suggests they might cause cancer – but nothing convincing. </p>
<p>These categories can be confusing, because they refer only to the strength of the evidence that something can cause cancer, not the degree of risk. Group 1 for example includes smoking, alcohol, <a href="https://theconversation.com/not-all-processed-meats-carry-the-same-cancer-risk-64622">processed meat</a>, plutonium and sunlight. There’s convincing evidence each one can cause cancer. </p>
<p>But the actual risks are very different and depend on amount and exposure. For instance, plutonium and smoking are best avoided, but there’s no reason to avoid processed meat or alcohol completely.</p>
<figure class="align-center ">
<img alt="A hand holds a cigarette." src="https://images.theconversation.com/files/535511/original/file-20230704-29-7padyv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/535511/original/file-20230704-29-7padyv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/535511/original/file-20230704-29-7padyv.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/535511/original/file-20230704-29-7padyv.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/535511/original/file-20230704-29-7padyv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/535511/original/file-20230704-29-7padyv.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/535511/original/file-20230704-29-7padyv.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">Smoking is known to cause cancer.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/harmful-habit-hand-holding-cigarette-smoke-1885761310">Oakland Images/Shutterstock</a></span>
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<p>While the IARC assesses the hazard, it’s JECFA’s job to assess the risk and make a recommendation about the <a href="https://apps.who.int/iris/bitstream/handle/10665/37578/9241542705-eng.pdf">acceptable daily intake</a>. </p>
<p>Their assessment will also be published on July 14, but there hasn’t been an indication in the media reports what it will say. It’s possible the acceptable daily intake will remain at 40mg per kilogram of body weight, or it may be reduced. Without having access to the data, is impossible to predict. </p>
<h2>The evidence so far</h2>
<p>The last review of aspartame’s safety was <a href="https://www.efsa.europa.eu/en/press/news/131210">conducted by EFSA</a> in 2013. This review didn’t find any new evidence that aspartame causes cancer and confirmed previous reviews by other regulators.</p>
<p>One compound that was of particular interest was <a href="https://www.efsa.europa.eu/en/efsajournal/pub/3496">methanol</a>, which is formed in the gut when aspartame is broken down and converted into formaldehyde by the human body. Formaldehyde is a known carcinogen (group 1). However, the amount that can form after the consumption of aspartame is much lower than what the body produces naturally.</p>
<p>In the interim there has been some data from a French study, which asked participants to provide information about their diet and followed them up for several years afterwards. This research suggested high consumption of aspartame <a href="https://journals.plos.org/plosmedicine/article?id=10.1371/journal.pmed.1003950">increases cancer risk</a>.</p>
<p>However, the results are difficult to interpret as obesity is <a href="https://www.wcrf.org/diet-activity-and-cancer/risk-factors/obesity-weight-gain-and-cancer">an independent risk factor</a> for cancer and people who are obese often use sweeteners. It’s also difficult to estimate aspartame intake accurately <a href="https://theconversation.com/a-whole-new-way-of-doing-nutrition-research-148352">from diet data alone</a>.</p>
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Read more:
<a href="https://theconversation.com/artificial-sweeteners-linked-to-diabetes-and-obesity-95314">Artificial sweeteners linked to diabetes and obesity</a>
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<p>It’s likely that the upcoming assessments will include this data and therefore provide a better estimate of aspartame’s risk. Until then, there is no reason for concern. Aspartame has been scrutinised for a long time and the classification of “possibly carcinogenic” suggests it’s unlikely there will be any major change in assessment or implications for consumers.</p><img src="https://counter.theconversation.com/content/208895/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Gunter Kuhnle has received research funding from Mars, Inc.</span></em></p>Reports have indicated the artificial sweetener aspartame will be classified as ‘possibly carcinogenic to humans’ by the WHO. Here’s what that means – and doesn’t mean.Gunter Kuhnle, Professor of Nutrition and Food Science, University of ReadingLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2061752023-06-08T12:30:25Z2023-06-08T12:30:25ZWHO’s recommendation against the use of artificial sweeteners for weight loss leaves many questions unanswered<figure><img src="https://images.theconversation.com/files/530408/original/file-20230606-14983-a38265.jpg?ixlib=rb-1.1.0&rect=26%2C8%2C5798%2C3763&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Sugar alternatives go by many names including artificial sweeteners, low-calorie sweeteners and nonsugar sweeteners.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/food-service-tray-with-sugar-packets-salt-and-royalty-free-image/1000353706?phrase=artificial+sweeteners&adppopup=true">Marie LaFauci/Moment via Getty Images</a></span></figcaption></figure><p>Do low-calorie sweeteners help with weight management? And are they safe for long-term use?</p>
<p>This is among the most controversial topics in nutritional science. In early May 2023, the World Health Organization issued a statement that cautions <a href="https://www.who.int/publications/i/item/9789240073616">against the use of nonsugar sweeteners</a> for weight loss except for people who have preexisting diabetes. </p>
<p>The WHO based its new recommendation on a <a href="https://www.who.int/publications/i/item/9789240046429">2022 systematic review and meta-analysis of scientific studies</a> on nonsugar sweetener consumption in humans. This type of study reviews a large body of research to draw a broad conclusion.</p>
<p>Based on its interpretation of that large-scale review, the WHO recommended <a href="https://www.who.int/news/item/15-05-2023-who-advises-not-to-use-non-sugar-sweeteners-for-weight-control-in-newly-released-guideline">against using artificial sweeteners for weight control</a> and concluded that there may be health risks associated with habitual consumption of nonsugar sweeteners over the long term. However, the WHO also acknowledged that the existing evidence is not conclusive and that more research needs to be done.</p>
<p>As neuroscientists, we study how dietary factors such as sweeteners affect the brain’s ability to perform critical functions, including metabolism, <a href="https://www.schierlab.com/">appetite</a>, and <a href="https://kanoskilab.com/">learning and memory</a>. </p>
<p>We found the WHO’s advisory surprising based on the study’s equivocal results. Determining the answers to these questions is immensely challenging, and public health messaging around recommendations can send mixed messages.</p>
<h2>‘Healthy’ versus ‘unhealthy’ sugars</h2>
<p>Natural sugars like glucose and fructose, together with fiber and other nutrients, are found in many food sources that are considered healthy, such as fruit. However, these simple carbohydrates have been increasingly added into manufactured food products, especially beverages. Sugar-sweetened beverages are usually high in calories and offer little else in the way of nutrition.</p>
<p>In the early 20th century, food and beverage manufacturers began incorporating naturally and chemically derived substances that satisfy sweet cravings but contain significantly fewer calories than natural sugars – and, in some cases, zero calories. Sugar substitutes became particularly widespread in the 1950s with the increasing popularity of diet sodas. Since then, consumers have <a href="https://doi.org/10.1016/j.physbeh.2016.03.030">increasingly turned to these sugar substitutes</a> in their everyday lives. </p>
<p>Sugar substitutes go by many names, including high-intensity sweeteners, artificial sweeteners, nonnutritive sweeteners, low-calorie sweeteners and, as termed in the WHO report, nonsugar sweeteners.“ These include synthetic compounds like sucralose, acesulfame potassium and aspartame, and naturally derived ones, such as those from the plant <em>Stevia rebaudiana</em>, among many others. </p>
<p>Each nonsugar sweetener has a unique chemical structure, but they all activate sweet taste receptors at very low concentrations. This means that you need to add only a tiny amount of them to sweeten your coffee or tea, as opposed to heaping spoonfuls of natural sugar.</p>
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<iframe width="440" height="260" src="https://www.youtube.com/embed/hAJrLMfpZBw?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Nonsugar sweeteners are found in many soft drinks, sports drinks and energy bars.</span></figcaption>
</figure>
<h2>Sugar substitutes and the quest for weight loss</h2>
<p>Obesity and its associated metabolic conditions, <a href="https://theconversation.com/drugs-that-melt-away-pounds-still-present-more-questions-than-answers-but-ozempic-wegovy-and-mounjaro-could-be-key-tools-in-reducing-the-obesity-epidemic-205549">like diabetes</a> and cardiovascular disease, are now among the leading <a href="https://www.cdc.gov/obesity/data/adult.html">causes of preventable death</a> in the U.S. The <a href="https://www.worldobesity.org/resources/resource-library/world-obesity-atlas-2022">obesity epidemic</a> has been linked in part to an increase in added sugar consumption over the past century. </p>
<p>In order to help address it, in 2015 the <a href="https://www.who.int/publications/i/item/9789241549028">WHO issued specific recommendations</a> to reduce sugar intake and adopt healthier diets. </p>
<p>But <a href="https://theconversation.com/a-taste-for-sweet-an-anthropologist-explains-the-evolutionary-origins-of-why-youre-programmed-to-love-sugar-173197">humans are hard-wired</a> to find the <a href="https://doi.org/10.1016/s0278-2626(03)00014-9">sweet taste of sugars pleasurable</a>, and the tastiness of real sugar makes it difficult for most of us to remove it from our diets. </p>
<p>Sugar substitutes were designed to help. The math seems straightforward: Replacing your favorite 12-ounce sugar-sweetened beverage that contains 150 calories with an artificially sweetened beverage of the same volume that contains zero calories should allow you to reduce the number of calories you take in each day and reduce your body weight over time. </p>
<p>But the science is not so straightforward. Research from <a href="https://doi.org/10.1080/17470218.2011.552729">both animal models and humans</a> indicates that <a href="https://doi.org/10.1172/jci.insight.167266">habitual nonsugar sweetener consumption</a> can lead to <a href="https://doi.org/10.2337/dc19-0734">long-term negative metabolic outcomes</a> and <a href="https://doi.org/10.3390/nu11122928">body weight gain</a>.</p>
<p>However, there are conflicting studies from <a href="https://doi.org/10.1016/j.appet.2016.05.011">animal models</a> <a href="https://doi.org/10.1038/s41430-019-0461-6">and humans</a> that have not found significant body weight gain associated with nonsugar sweeteners consumption.</p>
<h2>Parsing the health impacts</h2>
<p>Regardless of any potential benefits nonsugar sweeteners may have for weight control, their use must also be considered in the context of overall health. </p>
<p>Agencies like the WHO and the U.S. Food and Drug Administration periodically review available evidence and assess the safety of various food additives, including nonsugar sweeteners, for use in foods and beverages within what is called an <a href="https://www.fda.gov/food/food-additives-petitions/high-intensity-sweeteners">acceptable daily intake</a> limit. In this context, the acceptable daily intake is based on the estimated amount of a specific nonsugar sweetener that can be safely consumed daily over one’s entire life without adverse effects on health.</p>
<p>Each agency sets its own daily allowance based on the best available data. But because these experiments cannot account for all possible conditions in which these substances are used in real life, it is critical that scientists continue to investigate the health effects of food additives. </p>
<p>The authors of the WHO report relied on three main types of published research studies to determine whether nonsugar sweetener consumption was linked to adverse health effects. The gold standard for assessing causation is what are called <a href="https://doi.org/10.1111%2F1471-0528.15199">randomized controlled trials</a>. </p>
<p>In these studies, people are randomly assigned to either an experimental group – which receives the experimental substance, such as a nonsugar sweetener – or a control group – which receives a placebo or different substance. Participants in both groups are then tracked for a period of time, typically weeks or months. The majority of studies involving randomized controlled trials on nonsugar sweeteners to date involve this type of comparison, with nonsugar sweeteners replacing consumption of natural sugar-sweetened beverages. </p>
<p>The analysis of almost <a href="https://www.who.int/publications/i/item/9789240046429">50 randomized controlled trials</a> on which the WHO based its recommendation found modest benefits of using nonsugar sweeteners for weight loss and determined that the habitual use of those nonsugar sweeteners did not lead to diabetes symptoms or indicators of cardiovascular disease. But it did find that the use of nonsugar sweeteners was associated with a higher ratio of total cholesterol to HDL, short for high-density lipoprotein, which is considered the "good cholesterol.”</p>
<p>That means that habitual consumers of artificial sweetener had more of the low-density lipoprotein, or LDL version, in their system. That form of “bad cholesterol” is a <a href="https://www.cdc.gov/cholesterol/ldl_hdl.htm">risk factor for heart disease</a>. </p>
<p>However, other potential adverse consequences of consuming nonsugar sweeteners may take more time to appear than can be identified in the limited time frame of a randomized controlled trial. </p>
<p>The authors also evaluated what are called prospective cohort studies. Those studies track participants’ self-reported use of sweeteners alongside health outcomes, oftentimes over many years. They also took into account case-control studies, which identify people with or without a certain health issue, such as cancer, and then use available health records and interviews to determine the extent of nonsugar sweetener use in their past. </p>
<p>Examination of the cohort and case-control studies found that regular consumption of nonsugar sweetener was associated with increased fat accumulation, higher body mass index and increased incidence of <a href="https://www.cdc.gov/diabetes/basics/type2.html">Type 2 diabetes</a>. Those findings differ from the outcomes of the randomized control studies. </p>
<p>Analysis of the cohort and case-control studies also concluded that a history of regular nonsugar sweetener use was linked to increased frequency of stroke, hypertension, other adverse cardiovascular events and, in pregnant people, an increased risk for premature birth. The frequency of cancer in nonsugar sweetener consumers was very low in general, though <a href="https://www.fda.gov/food/food-additives-petitions/aspartame-and-other-sweeteners-food#">saccharin, an FDA-approved sweetener</a> found in many food products, was associated with a bladder cancer. </p>
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<iframe width="440" height="260" src="https://www.youtube.com/embed/GxGhTve6gSA?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">The history of artificial sweeteners.</span></figcaption>
</figure>
<h2>Caveats and takeaways</h2>
<p>On the face of it, these results are alarming, but they need to be taken with a grain of salt. As the WHO report points out, these studies have significant limitations that need to be considered. </p>
<p>Take, for example, in the cohort and case-control studies, that higher <a href="https://www.nhlbi.nih.gov/health/educational/lose_wt/BMI/bmicalc.htm">body mass index, or BMI</a>, was associated with greater nonsugar sweetener intake and poorer health outcomes. One possibility is that people with obesity used nonsugar sweeteners to help cut calories more than others without obesity. This makes it difficult to determine whether the disease is caused by sustained artificial sweetener use or by the other underlying conditions associated with obesity. </p>
<p>Additionally, the way nonsugar sweeteners are consumed is not controlled in these types of studies. So negative health outcomes could be associated with other affiliated harmful behaviors, such as more sugar or fat in the diet. </p>
<p>The picture is very mixed on both the benefits of nonsugar sweeteners for weight loss and their ties to adverse health issues. The WHO’s recommendation seems to have weighed the cohort and case-control studies over the randomized controlled ones, a decision that we found puzzling in light of the limitations of these studies for assessing whether nonsugar sweeteners have a causal role in disease.</p>
<p>As with all health-related choices, the science is complex. In our view, grabbing a diet drink to offset the calories in a slice of chocolate cake every once in a while will likely not be harmful for your health or lead to a significant weight change.</p><img src="https://counter.theconversation.com/content/206175/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Lindsey Schier receives funding from the National Institutes of Health (NIDCD).</span></em></p><p class="fine-print"><em><span>Scott Kanoski receives funding from the National Institutes of Health. </span></em></p>The WHO report concluded that habitual use of nonsugar sweeteners is linked to a modest increase in diabetes, hypertension and stroke. But the research it’s based on has limitations.Lindsey Schier, Assistant Professor of Biological Sciences, USC Dornsife College of Letters, Arts and SciencesScott Kanoski, Associate Professor of Biological Science, USC Dornsife College of Letters, Arts and SciencesLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1797092022-03-24T18:13:26Z2022-03-24T18:13:26ZSweeteners may be linked to increased cancer risk – new research<figure><img src="https://images.theconversation.com/files/454089/original/file-20220324-17-1uexs5k.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C4867%2C3240&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">The sweetener aspartame is found is many common foods and drinks, such as diet sodas. </span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/thirsty-asian-young-woman-girl-holding-2105136650">Kmpzzz/ Shutterstock</a></span></figcaption></figure><p>Sweeteners have long been suggested to be bad for our health. Studies have linked consuming too many sweeteners with conditions such as <a href="https://link.springer.com/article/10.1007/s11894-017-0602-9">obesity</a>, <a href="https://www.sciencedirect.com/science/article/pii/S1043276013000878?casa_token=hmictGrhvYIAAAAA:iQc3yRiZOK5NKDKj9CbbG2p86xphcvXRkjjWTqWOgr4LTbjNaekoSDHft7kbo25Yudw8gSPBOg">type 2 diabetes and cardiovascular disease</a>. But links with cancer have been less certain.</p>
<p>An artificial sweetener, called cyclamate, that was sold in the US in the 1970s was shown to <a href="https://pubmed.ncbi.nlm.nih.gov/5432702/">increase bladder cancer</a> in rats. However, human physiology is very different from rats, and observational studies <a href="https://www.nejm.org/doi/full/10.1056/NEJM198003063021001">failed to find a link</a> between the sweetener and cancer risk in humans. Despite this, the media <a href="https://www.sciencedirect.com/science/article/pii/S0923753419510377">continued to report a link</a> between sweeteners and cancer.</p>
<p>But now, a <a href="http://journals.plos.org/plosmedicine/article?id=10.1371/journal.pmed.1003950">study published in PLOS Medicine</a> which looked at over 100,000 people, has shown that those who consume high levels of some sweeteners have a small increase in their risk of developing certain types of cancer.</p>
<p>To assess their intake of artificial sweeteners, the researchers asked the participants to keep a food diary. Around half of the participants were followed for more than eight years. </p>
<p>The study reported that aspartame and acesulfame K, in particular, were associated with increased cancer risk – especially breast and obesity-related cancers, such as colorectal, stomach and prostate cancers. This suggests that removing some types of sweeteners from your diet may reduce the risk of cancer. </p>
<h2>Cancer risk</h2>
<p>Many common foods <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4899993/">contain sweeteners</a>. These food additives <a href="https://link.springer.com/article/10.1007/s13197-011-0571-1">mimic the effect of sugar</a> on our taste receptors, providing intense sweetness with no or very few calories. Some sweeteners occur naturally (such as stevia or <a href="https://pubmed.ncbi.nlm.nih.gov/25692980/">yacon syrup</a>). Others, such as aspartame, are artificial. </p>
<p>Although they have few or no calories, sweeteners still have an effect on our health. For example, aspartame <a href="https://www.sciencedirect.com/science/article/abs/pii/S1044579X98900773">turns into formaldehyde</a> (<a href="https://www.cancer.gov/about-cancer/causes-prevention/risk/substances/formaldehyde/formaldehyde-fact-sheet#:%7E:text=The%20International%20Agency%20for%20Research,Report%20on%20Carcinogens%20(3).">a known carcinogen</a>) when the body digests it. This could potentially see it accumulate in cells and cause them to become cancerous.</p>
<p>Our cells are hard-wired to self-destruct when they become cancerous. But aspartame has been shown to “<a href="https://www.sciencedirect.com/science/article/pii/S1319562X15001345">switch off</a>” the genes that tell cancer cells to do this. Other sweeteners, including sucralose and saccharin, have also been shown to damage DNA, which can <a href="https://www.tandfonline.com/doi/abs/10.3109/01480545.2014.966381">lead to cancer</a>. But this has only been shown in cells in a dish rather than in a living organism.</p>
<figure class="align-center ">
<img alt="A person puts aspartame sweetener into their mug of tea." src="https://images.theconversation.com/files/454090/original/file-20220324-25-7y52d5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/454090/original/file-20220324-25-7y52d5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=399&fit=crop&dpr=1 600w, https://images.theconversation.com/files/454090/original/file-20220324-25-7y52d5.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=399&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/454090/original/file-20220324-25-7y52d5.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=399&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/454090/original/file-20220324-25-7y52d5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=501&fit=crop&dpr=1 754w, https://images.theconversation.com/files/454090/original/file-20220324-25-7y52d5.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=501&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/454090/original/file-20220324-25-7y52d5.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">Aspartame can affect our cells and gut microbiome.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/put-aspartame-cup-coffee-close-1433384099">RVillalon/ Shutterstock</a></span>
</figcaption>
</figure>
<p>Sweeteners can also have a profound effect on <a href="https://www.tandfonline.com/doi/full/10.1080/19490976.2015.1017700">the bacteria that live in our gut</a>. Changing the bacteria in the gut can <a href="https://www.sciencedirect.com/science/article/pii/S153561081830120X">impair the immune system</a>, which could mean they no longer identify and remove cancerous cells. </p>
<p>But it’s still unclear from these animal and cell-based experiments precisely how sweeteners initiate or support cancerous changes to cells. Many of these experiments would also be difficult to apply to humans because the amount of sweetener was given at much higher doses than a human would ever consume.</p>
<p>The results from previous research studies are limited, largely because most studies on this subject have only observed the effect of consuming sweeteners without comparing against a group that hasn’t consumed any sweeteners. A recent systematic review of <a href="https://onlinelibrary.wiley.com/doi/full/10.1111/ijcp.12703?casa_token=CZP_a8ydZbwAAAAA%3AFKfYJyy8EuFqO2MIKuOXojzfhRuiDaIyeSzVF_YLPkg53-pwQkMrKQ2XdM7fd_1zabfc_IEoGSKWZDQ">almost 600,000 participants</a> even concluded there was limited evidence to suggest heavy consumption of artificial sweeteners may increase the risk of certain cancers. A <a href="https://www.bmj.com/content/364/bmj.k4718">review in the BMJ</a> came to a similar conclusion.</p>
<p>Although the findings of this recent study certainly warrant further research, it’s important to acknowledge the study’s limitations. First, food diaries can be unreliable because people <a href="https://jech.bmj.com/content/54/8/611.abstract">aren’t always honest</a> about what they eat or they may forget what they have consumed. Although this study collected food diaries every six months, there’s still a risk people weren’t always accurately recording what they were eating and drinking. Though the researchers partially mitigated this risk by having participants take photos of the food they ate, people still might not have included all the foods they ate. </p>
<p>Based on current evidence, it’s generally agreed that using artificial sweeteners is <a href="https://www.scirp.org/html/13-8204292_84959.htm?pagespeed=noscript">associated with increased body weight</a> – though researchers aren’t quite certain whether sweeteners directly cause this to happen. Although this recent study took people’s body mass index into account, it’s possible that <a href="https://www.bmj.com/content/356/bmj.j477">changes in body fat</a> may have <a href="https://www.nature.com/articles/nrc3967">contributed to the development</a> of many of these <a href="https://acsjournals.onlinelibrary.wiley.com/doi/full/10.1002/cncr.29552">types of cancers</a> – not necessarily the sweeteners themselves. </p>
<p>Finally, the risk of developing cancer in those who consumed the highest levels of artificial sweeteners compared with those who consumed the lowest amounts was modest – with only at 13% higher relative risk of developing cancer in the study period. So although people who consumed the highest amounts of sweetener had an increased risk of developing cancer, this was still only slightly higher than those with the lowest intake.</p>
<p>While the link between sweetener use and diseases, including cancer, is still controversial, it’s important to note that not all sweeteners are equal. While sweeteners such as aspartame and saccharin may be associated with ill health, not all sweeteners are. Stevia, produced from the <em>Stevia rebaudiana</em> plant, has been reported to be useful in controlling <a href="https://academic.oup.com/jn/article/148/7/1186S/5049670?login=true">diabetes and body weight</a>, and may also <a href="https://www.tandfonline.com/doi/full/10.3109/09637480903193049?casa_token=lO5FkbXzMEAAAAAA%3AhDdqp3moaBVdiKVBwE3xovSFl63vwVHpP2prqAEJveyAeFglbn_Z23BPXAkuUMdS27xSXbEnvW5c">lower blood pressure</a>. The naturally occurring sugar alcohol, xylitol, may also support the <a href="https://link.springer.com/article/10.1007/s00253-020-10708-7">immune system and digestion</a>. Both <a href="http://www.scielo.org.ar/scielo.php?pid=S1852-48342012000200003&script=sci_arttext&tlng=en">stevia</a> and <a href="https://www.cochranelibrary.com/cdsr/doi/10.1002/14651858.CD010743.pub2/full">xylitol</a> have also been shown to protect from tooth decay, possibly because they kill bad oral bacteria.</p>
<p>So the important choice may be not the amount of sweetener you eat but the type you use.</p><img src="https://counter.theconversation.com/content/179709/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>James Brown has previously received funding from the EU Horizon 2020 scheme to study personalised approaches to food choices.</span></em></p>A study of over 100,000 people found aspartame and acesulfame K in particular may increase risk of developing cancer somewhat.James Brown, Associate Professor in Biology and Biomedical Science, Aston UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1185712019-07-01T10:52:11Z2019-07-01T10:52:11ZSugar substitutes: Is one better or worse for diabetes? For weight loss? An expert explains<figure><img src="https://images.theconversation.com/files/280570/original/file-20190620-149814-17p8d8c.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Sugar and artificial sweeteners comes in many shapes and colors.</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/flat-lay-composition-different-types-sugar-1057731923?studio=1">New Africa/Shutterstock.com</a></span></figcaption></figure><p>Wandering through the grocery store, it is easy to be overwhelmed by the numerous brands and health claims on the dozens of sugar substitutes. It can be particularly confusing for those with diabetes or pre-diabetes who must keep their blood sugar in check and control their weight. </p>
<p>With the <a href="https://www.who.int/news-room/fact-sheets/detail/diabetes">growing diabetes and obesity epidemic</a>, there has been increasing awareness around the use of added sugars in foods. The most recent edition of the <a href="https://health.gov/dietaryguidelines/2015/">U.S. Dietary Guidelines for Americans</a> recommends that added sugars should be kept to less than 10% of the calories consumed, which turns out to be roughly 270 calories per day. </p>
<p>This is because “added sugars” add sweetness or flavor but add very little nutritional value. Because of this trend, the food industry has embarked on a quest to find or develop the perfect substitute to replace sugar – with the same taste and none of the calories that lead to weight gain. </p>
<p>As a pharmacist who is also board certified in advanced diabetes management, I talk to patients every day about blood sugars and ways to help them take control of their diabetes. They often ask me whether the perfect substitute to sugar has been found. The short answer is no. Here is the long answer.</p>
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<img alt="" src="https://images.theconversation.com/files/281801/original/file-20190628-94716-tinmxq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/281801/original/file-20190628-94716-tinmxq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/281801/original/file-20190628-94716-tinmxq.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/281801/original/file-20190628-94716-tinmxq.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/281801/original/file-20190628-94716-tinmxq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/281801/original/file-20190628-94716-tinmxq.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/281801/original/file-20190628-94716-tinmxq.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">
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<span class="caption">Many artificial sweeteners are available at the grocery store.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/subang-jaya-malaysia-23rd-december-2017-781850755?studio=1">Zety Akhzar/Shutterstock.com</a></span>
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<h2>Sugar alcohols</h2>
<p>Sugar substitutes can be categorized into two main groups: sugar alcohols and high intensity sweeteners. The sugar alcohols include sorbitol, xylitol, lactitol, mannitol, erythritol and maltitol. <a href="https://www.fda.gov/food/food-additives-petitions/high-intensity-sweeteners">High-intensity sweeteners</a> include saccharin, aspartame, acesulfame potassium (Ace-K), sucralose, neotame, advantame, stevia, and Siraitia grosvenorii Swingle fruit extract (SGFE).</p>
<p><a href="http://www.diabetes.org/food-and-fitness/food/what-can-i-eat/understanding-carbohydrates/sugar-alcohols.html">Sugar alcohols</a> are often found in toothpaste, chewing gum, and some “sugar-free” foods. They are carbohydrates with a chemical structure that resembles sugar, but also the components that make them an alcohol. They are about 25-100% sweeter than sugar and have <a href="https://doi.org/10.1016/j.foodres.2019.03.019">a similar taste</a>. But here is the catch: They are not calorie free. Most have <a href="http://doi.org/10.1016/j.jand.2012.03.009">between 1.5 and two calories per gram</a>. Now compare the calorie count to sugar, also known as sucrose, which has four calories per gram – twice as much. </p>
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<a href="https://images.theconversation.com/files/281805/original/file-20190628-94708-lua3oo.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/281805/original/file-20190628-94708-lua3oo.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/281805/original/file-20190628-94708-lua3oo.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=847&fit=crop&dpr=1 600w, https://images.theconversation.com/files/281805/original/file-20190628-94708-lua3oo.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=847&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/281805/original/file-20190628-94708-lua3oo.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=847&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/281805/original/file-20190628-94708-lua3oo.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1064&fit=crop&dpr=1 754w, https://images.theconversation.com/files/281805/original/file-20190628-94708-lua3oo.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1064&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/281805/original/file-20190628-94708-lua3oo.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1064&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">Which foods have a low glycemic index and are better choices for those trying to control their blood sugar.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-vector/chart-infographics-vector-drawn-glycemic-index-390100423?src=lLctBPmzaHfK2TKO97-FXw-1-5&studio=1">Irina Izograf</a></span>
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<p>Although sugar alcohols contain fewer calories, they will still increase a patient’s blood sugar, especially when eaten in excess. When compared to sugar, the effect is less dramatic though. This is because of how these molecules are processed in the body. We measure this using the glycemic index. </p>
<p>The glycemic index is a reference to how quickly a food is broken down and absorbed. The higher the number, the more quickly the food breaks down and the faster the sugar goes into the blood. Sucrose has a <a href="https://www.glycemicindex.com/">glycemic index</a> of 65; whereas sugar alcohols, like xylitol, have a glycemic index of around seven. This means that sugar alcohols are harder to digest, and cause a slower and lower increase in post-meal blood sugars – which is typically better for people with diabetes. Because sugar alcohols are harder for the body to break down though, some of them remain in the gut, and if a person consumes too much they may experience <a href="http://doi.org/10.1016/j.jand.2012.03.009">digestive complaints like</a> gas, cramping and diarrhea.</p>
<p>Here is the other downside to foods containing sugar alcohols: They often have <a href="http://www.diabetes.org/food-and-fitness/food/what-can-i-eat/understanding-carbohydrates/sugar-alcohols.html">higher quantities of fat or salt</a> to make up for the lower sugar content.</p>
<h2>Artificial sweeteners</h2>
<p>High-intensity sweeteners, are zero- or low-calorie alternatives to sugar. They are made from a variety of sources, and are 100 to 20,000 times as sweet as sugar. Some leave a bitter or metallic taste behind. Two newer substitutes – stevia and SGFE – come from plants and are at times referred to as “natural” substitutes. </p>
<p>According to the <a href="https://care.diabetesjournals.org/content/42/Supplement_1">American Diabetes Association 2019 guidelines</a>, the use of high-intensity sweeteners may decrease calorie and carbohydrate intake. However, you cannot replace these “free” calories with calories from other food sources, you will lose or the benefits on blood sugar control and weight loss. </p>
<p>Researchers have seen this in some of the studies on high-intensity sweeteners. Some of the trials show <a href="http://doi.org/10.1503/cmaj.161390">no difference or even a possible increase in weight</a>. But in other studies where intake of food is better regulated and patients don’t replace these free calories with other high-caloric foods, <a href="http://doi.org/10.3945/ajcn.113.082826">the weight loss is maintained</a>. </p>
<h2>The takeaway</h2>
<p>All sugar substitutes are labeled as food additives and are under the regulation of the U.S. Food and Drug Administration. The latest trend has been labeling some of the sugar substitutes as “derived from plants” or “natural.” That does not necessarily mean that these are safer or more effective in blood sugar control or weight loss. If it is used in excess, side effects such as bloating or diarrhea may still result. </p>
<p>Several concerns by researchers have been raised about high-intensity sweeteners – saccharin and aspartame – and cancer. To date, the National Cancer Institute has concluded that there is no clear evidence that any of the high-intensity sweeteners is <a href="https://www.cancer.gov/about-cancer/causes-prevention/risk/diet/artificial-sweeteners-fact-sheet">associated with an increased risk of cancer</a>. </p>
<p>As a pharmacist specializing in advanced diabetes, I talk to patients every day about how to control their blood sugar level and their diabetes. There are three main ways to do that: medication, increased activity and diet. The last two are probably more important in the long run. </p>
<p>If diet and activity level never change, it is really hard to help patients bring their blood sugars down. Medication after medication will likely have to be added. With this comes the potential for side effects. So if I can persuade patients to make changes to their diet, like switching to a beverage with a sugar substitute, it makes a huge difference in helping to control blood sugars and the dose of medications.</p>
<p>The overall focus for diabetes management should be on reducing the consumption of sugar-sweetened beverages and foods. If you can switch one of these sugar-sweetened products to a food that has a high-intensity sugar substitute, that is better. But best of all is consuming <a href="https://care.diabetesjournals.org/content/42/Supplement_1">food and drinks that are not highly processed</a> and do not have added sugars.</p><img src="https://counter.theconversation.com/content/118571/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Jamie Pitlick 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>There is a huge variety of sugar substitutes available. What’s the difference? Is one better for controlling blood sugar levels for diabetes? Is one better for individuals trying to lose weight?Jamie Pitlick, Associate Professor of Pharmacy Practice , Drake UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/961812018-05-17T10:42:12Z2018-05-17T10:42:12ZDiet soda may be hurting your diet<figure><img src="https://images.theconversation.com/files/218510/original/file-20180510-34027-134a0es.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Coca-Cola is the world's most popular carbonated soft drink. The original is made with sugar, but the others contain artificial sweeteners that are now linked to a rise in obesity and diabetes.</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/download/confirm/230138068?src=NUy_997g4GskZiRl7oIRGQ-1-80&size=huge_jpg">By Chones/shutterstock.com</a></span></figcaption></figure><p>Artificial sweeteners are everywhere, but the jury is still out on whether these chemicals are harmless. Also called non-nutritive sweeteners, these can be synthetic – such as saccharin and aspartame – or naturally derived, such as steviol, which comes from the Stevia plant. To date, the U.S. Food and Drug Administration has approved <a href="https://www.fda.gov/Food/IngredientsPackagingLabeling/FoodAdditivesIngredients/ucm397725.htm">six types of artificial and two types of natural non-nutritive sweeteners</a> for use in food. </p>
<p>That’s been great news for those working hard to curb their sugar consumption. <a href="https://doi.org/10.3945/ajcn.111.030833">Aspartame</a>, for example, is found in more than 6,000 foods worldwide, and about 5,000-5,500 tons are consumed every year in the United States alone. </p>
<p>The American Diabetes Association – the most well-respected professional group focusing on diabetes – <a href="http://www.diabetes.org/food-and-fitness/food/what-can-i-eat/making-healthy-food-choices/what-can-i-drink.html">officially recommends diet soda as an alternative</a> to sugar-sweetened beverages. To date, seven U.S. municipalities have imposed a sugary beverage tax to discourage consumption.</p>
<p>However, recent medical studies suggest that policymakers eager to implement a soda tax may also want to include diet drinks because these sweeteners may be contributing to chronic diabetes and cardiovascular diseases as well.</p>
<h2>Why are these sweeteners calorie-free?</h2>
<p>The key to these virtually calorie-free sweeteners is that they are not broken down during digestion into natural sugars like glucose, fructose and galactose, which are then either used for energy or converted into fat. </p>
<p>Non-nutritive sweeteners have different byproducts that are not converted into calories. Aspartame, for example, undergoes a different metabolic process that doesn’t yield simple sugars. Others such as saccharin and sucralose are not broken down at all, but instead are absorbed directly into the bloodstream and excreted in the urine. </p>
<p>Theoretically, these sweeteners should be a “better” choice than sugar for diabetics. Glucose stimulates release of insulin, a hormone that regulates blood sugar levels. Type 2 diabetes occurs when the body no longer responds as well to insulin as it should, leading to higher levels of glucose in the blood that damages the nerves, kidneys, blood vessels and heart. Since non-nutritive sweeteners aren’t actually sugar, they should sidestep this problem.</p>
<h2>Artificial sweeteners, your brain and your microbiome</h2>
<p>However, there is growing evidence over the last decade that these sweeteners can alter healthy metabolic processes in other ways, specifically in the gut. </p>
<p>Long-term use of these sweeteners has <a href="https://doi.org/10.2337/dc08-1799">been associated with a higher risk of Type 2 diabetes</a>. Sweeteners, such as saccharin, have been shown to <a href="http://doi.org/10.1038/nature13793">change the type and function of the gut microbiome</a>, the community of microorganisms that live in the intestine. Aspartame <a href="https://doi.org/10.1139/apnm-2016-0346">decreases the activity of a gut enzyme</a> that is normally protective against Type 2 diabetes. Furthermore, this response may be exacerbated by the “mismatch” between the body perceiving something as tasting sweet and the expected associated calories. The greater the discrepancy between the sweetness and actual caloric content, the <a href="http://doi.org/10.1016/j.cub.2017.07.018">greater the metabolic dysregulation</a>.</p>
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<p>Sweeteners have also been shown to change brain activity associated with eating sweet foods. A functional MRI exam, which studies brain activity by measuring blood flow, has shown that sucralose, compared to regular sugar, <a href="https://doi.org/10.1016/j.appet.2011.12.001">decreases activity in the amygdala</a>, a part of the brain involved with taste perception and the experience of eating. </p>
<p>Another study revealed that longer-term and higher diet soda consumption are linked to <a href="https://doi.org/10.1016/j.physbeh.2012.05.006">lower activity in the brain’s “caudate head,”</a> a region that mediates the reward pathway and is necessary for generating a feeling of satisfaction. Researchers have hypothesized that this decreased activity could lead a diet soda drinker to compensate for the lack of pleasure they now derive from the food by increasing their consumption of all foods, not just soda. </p>
<p>Together these cellular and brain studies may explain why people who consume sweeteners still have a <a href="https://doi.org/10.1371/journal.pone.0167241">higher risk of obesity</a> than individuals who don’t consume these products. </p>
<p><a href="https://doi.org/10.1503/cmaj.161390">As this debate on the pros and cons of these sugar substitutes rages on</a>, we must view these behavioral studies with a grain of salt (or sugar) because many diet soda drinkers – or any health-conscious individual who consumes zero-calorie sweeteners – already has the risk factors for obesity, diabetes, hypertension or heart disease. Those who are already overweight or obese may turn toward low-calorie drinks, making it look as though the diet sodas are causing their weight gain.</p>
<p>This same group may also be less likely to moderate their consumption. For example, those people may think that having a diet soda multiple times a week is much healthier than drinking one case of soda with sugar.</p>
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<p>These findings signal that consumers and health practitioners all need to check our assumptions about the health benefits of these products. Sweeteners are everywhere, from beverages to salad dressing, from cookies to yogurt, and we must recognize that there is no guarantee that these chemicals won’t increase the burden of metabolic diseases in the future. </p>
<p>As a physician of internal medicine specializing in general prevention and public health, I would like to be able to tell my patients what the true risks and benefits are if they drink diet soda instead of water. </p>
<p>Legislators considering soda taxes to encourage better dietary habits perhaps should think about including foods with non-nutritive sweeteners. Of course, there is an argument to be made for being realistic and pursuing the lesser of two evils. But even if the negative consequences of sugar substitutes doesn’t sway our tax policy – for now – at least the medical community should be honest with the public about what they stand to lose or gain, consuming these foods. </p>
<p><a href="https://theconversation.com/las-bebidas-light-pueden-perjudicar-tu-dieta-98534"><em>Leer en español</em></a>.</p><img src="https://counter.theconversation.com/content/96181/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Eunice Zhang 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>Mounting evidence suggests that artificial sweeteners are linked to chronic health problems like obesity and diabetes. Should there be a tax on these foods?Eunice Zhang, Clinical Instructor, University of California, Los AngelesLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/953142018-04-23T11:54:45Z2018-04-23T11:54:45ZArtificial sweeteners linked to diabetes and obesity<figure><img src="https://images.theconversation.com/files/215908/original/file-20180423-133876-1y79zs6.jpg?ixlib=rb-1.1.0&rect=0%2C38%2C998%2C624&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/download/confirm/97352366?src=Xz2aWr1ZNrer_09w80dfcA-1-57&size=medium_jpg">MSPhotographic/Shutterstock.com</a></span></figcaption></figure><p>Many countries have introduced a <a href="https://www.beveragedaily.com/Article/2017/12/20/Sugar-taxes-The-global-picture-in-2017">sugar tax</a> in order to improve the health of their citizens.
As a result, food and drink companies are changing their products to include low and zero-calorie sweeteners instead of sugar. However, there is <a href="https://theconversation.com/artificial-sweeteners-may-make-you-fat-93452">growing evidence</a> that sweeteners may have health consequences of their own. </p>
<p>New <a href="https://plan.core-apps.com/eb2018/abstract/382e0c7eb95d6e76976fbc663612d58a">research</a> from the US, presented at the annual Experimental Biology conference in San Diego, found a link with consuming artificial sweeteners and changes in blood markers linked with an increased risk of obesity and type 2 diabetes in rats. Does this mean we need to ditch sweeteners as well as sugar?</p>
<p>Sweeteners are generally “non-nutritive” substances meaning we can’t use them for energy. Some of these compounds are entirely synthetic chemicals, produced to mimic the taste of sugar. These include saccharin, sucralose and aspartame. Others sweeteners are refined from chemicals found in plants, such as stevia and xylitol. Collectively, sweeteners are being <a href="https://www.sciencedaily.com/releases/2017/01/170110101625.htm">consumed in increasing amounts</a> with most diet or low-calorie food and drink containing some form of non-nutritive sweetener.</p>
<h2>Combating or fuelling the obesity crisis?</h2>
<p>Artificially sweetened foods and drinks have become popular largely due to the <a href="http://www.who.int/mediacentre/factsheets/fs311/en/">growing worldwide obesity crisis</a>. As sugar contains four calories per gram, sweet foods and drinks are normally highly calorific. In principle, by removing these calories we reduce energy intake and this helps to prevent weight gain. </p>
<p>Increasingly, however, evidence suggests that consuming artificially sweetened products might be associated with an <a href="https://www.karger.com/Article/FullText/484566">increased risk of being overweight or obese</a>, although this is controversial. If true, it suggests that using sweeteners is <a href="https://onlinelibrary.wiley.com/doi/full/10.1038/oby.2008.284">fuelling, not fighting obesity</a>. Research has suggested that consuming lots of artificial sweeteners scrambles the bacteria in our gut, causing them to make our bodies <a href="https://www.nature.com/articles/nature13793">less tolerant to glucose</a>, the main building-block of sugar. </p>
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<a href="https://theconversation.com/artificial-sweeteners-may-make-you-fat-93452">Artificial sweeteners may make you fat</a>
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<p>The new research, from the Medical College of Wisconsin and Marquette University, looked at some biological effects of sweeteners in rats and in cell cultures. They wanted to know if artificial sweeteners affect how food is used and stored. These are called metabolic changes and the research combined many different aspects of metabolism to build an overall picture. </p>
<p>The team also looked at the impact of sweeteners on blood vessel health by studying how these substances affect the cells that form the inner lining of blood vessels. </p>
<p>The scientists gave rats food that was high in either sugar (glucose or fructose) or calorie-free artificial sweeteners (aspartame or acesulfame potassium). After three weeks they saw significant negative changes in both groups of rats. These changes included the concentrations of blood lipids (fats). </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/215920/original/file-20180423-133853-1930vzy.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/215920/original/file-20180423-133853-1930vzy.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=369&fit=crop&dpr=1 600w, https://images.theconversation.com/files/215920/original/file-20180423-133853-1930vzy.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=369&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/215920/original/file-20180423-133853-1930vzy.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=369&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/215920/original/file-20180423-133853-1930vzy.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=464&fit=crop&dpr=1 754w, https://images.theconversation.com/files/215920/original/file-20180423-133853-1930vzy.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=464&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/215920/original/file-20180423-133853-1930vzy.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=464&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Artificial sweeteners change how the body processes fat.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/download/confirm/114601549?src=Stb7G29glJyT2KCiyw3f1g-1-11&size=huge_jpg">ADA_photo/Shutterstock.com</a></span>
</figcaption>
</figure>
<p>They also found that acesulfame potassium, in particular, accumulated in the blood and harmed the cells that line blood vessels. The study authors state that these changes are “linked to obesity and diabetes”. These results suggest that consuming sweeteners change how the body processes fat and gets its energy at a cellular level.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/more-evidence-that-low-calorie-sweeteners-are-bad-for-your-health-81037">More evidence that low-calorie sweeteners are bad for your health</a>
</strong>
</em>
</p>
<hr>
<h2>Limit your intake</h2>
<p>What does this mean for the average consumer of artificial sweeteners? As the study was performed in animals and not humans it would be wrong to draw firm conclusions about what might happen in people. The findings of the study do, however, add to the growing body of research that suggests that sweeteners are not benign alternatives to sugar. </p>
<p>The European Food Safety Authority suggests <a href="https://www.efsa.europa.eu/en/topics/topic/sweeteners">a daily limit to most artificial sweeteners</a> of around five milligrams per kilogram of body weight, per day. With so many foods including artificial sweeteners now, it is relatively easy to reach this limit. </p>
<p>It is important to note that not all sweeteners are equal. This recent study focused on artificial sweeteners, like most of the research that has identified negative effects. Some sweeteners are associated with health benefits. </p>
<p>Stevia, for example, has been shown to <a href="https://www.ncbi.nlm.nih.gov/pubmed/20370653">improve blood pressure and glucose tolerance</a> while xylitol has been shown to help <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5320817/">prevent tooth decay</a>. This means that choosing the type of sweetener that you use may be more important than choosing a sweetener over sugar.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/coke-life-lands-a-blow-against-sugar-but-its-worthy-credentials-could-still-be-trouble-31208">Coke Life lands a blow against sugar, but its worthy credentials could still be trouble</a>
</strong>
</em>
</p>
<hr>
<p>It is likely that the best advice is the blandest: everything in moderation. There is no such thing as good or bad food, only good or bad amounts. Maybe avoid consuming too much of either sugar or sweetener, especially in drinks.</p><img src="https://counter.theconversation.com/content/95314/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>James Brown previously received funding from an independent food manufacturer to consult on their use of non-nutritive sweeteners</span></em></p><p class="fine-print"><em><span>Alex Conner 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>A new study in rats adds to the evidence that artificial sweeteners may be bad for your health.James Brown, Senior Lecturer in Biology and Biomedical Science, Aston UniversityAlex Conner, Senior Lecturer in Biomedical Sciences, University of BirminghamLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/810372017-07-18T10:57:13Z2017-07-18T10:57:13ZMore evidence that low-calorie sweeteners are bad for your health<figure><img src="https://images.theconversation.com/files/178471/original/file-20170717-6091-1cfa5s1.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/download/confirm/175095215?src=Ko8dmtm34FSZfzB6VKDZLw-1-2&size=medium_jpg">Monika Wisniewska/Shutterstock</a></span></figcaption></figure><p>Drinking beverages containing low-calorie sweeteners may not help you lose weight and may even be bad for your health, according to new research published in the <a href="http://www.cmaj.ca/content/189/28/E929">Canadian Medical Association Journal</a>. The researchers, who reviewed a number of studies, found that people who regularly consume low-calorie sweeteners (such as aspartame, sucralose and stevioside) tend have a higher risk of long-term weight gain, obesity, type 2 diabetes, hypertension and heart disease than those who don’t.</p>
<p>Obesity is a <a href="http://www.who.int/mediacentre/factsheets/fs311/en/">growing, global problem</a>, and <a href="http://www.bmj.com/content/346/bmj.e7492">excess sugar consumption</a> is suspected of being a major factor in this grim trajectory. In an effort to avoid the health consequences of consuming too much sugar, people have been switching to low-calorie sweeteners. Consumption of these sweeteners has increased significantly in recent years, and the trend is <a href="https://www.ncbi.nlm.nih.gov/pubmed/?term=Trends+in+the+consumption+of+low-calorie+sweeteners.+Physiol+Behav">expected to continue</a>. </p>
<p>However, a number of recent studies – including <a href="https://www.ncbi.nlm.nih.gov/pubmed/27129676">animal studies</a> – have suggested that low-calorie sweeteners may not be that good for your health. For example, there is some evidence that they may negatively affect <a href="https://www.ncbi.nlm.nih.gov/pubmed/23850261">glucose metabolism</a>, <a href="https://www.ncbi.nlm.nih.gov/pubmed/27090230">gut microbes</a> and <a href="https://www.ncbi.nlm.nih.gov/pubmed/23850261">appetite control</a>. But small, individual studies don’t always give a complete picture. In order to get a better idea of what low-calorie sweeteners are doing to our health, the researchers in this latest study conducted a systematic review with a meta-analysis. This means they pooled data from the best studies they could find and re-analysed the combined data in order to generate more reliable statistics.</p>
<p>For their review, the researchers analysed data from seven randomised controlled trials (the “gold standard” for clinical studies) and 30 observational studies. In all, the studies included 400,000 participants.</p>
<p>The trials, which included 1,003 participants who were followed for an average of six months, showed no consistent evidence that low-calorie sweeteners helped people manage their weight. The observational studies, which followed people for an average of ten years, found that people who regularly drank low-calorie sweetened drinks (one or more drinks a day) had an increased risk of moderate weight gain, hypertension, metabolic syndrome, type 2 diabetes and heart disease (including stroke).</p>
<p>Randomised controlled trials can prove that one thing causes another, but observational studies can only show an association between things. So we need to treat the findings from observational studies with more caution, as there may be other factors (known as “confounders”) that explain the associations. For example, it is possible that heavier people consume drinks with low-calorie sweeteners to try and lose weight, rather than that the consumption of these drinks <em>cause</em> an increase in weight. </p>
<p>The review also only looked at beverages that contained low-calorie sweeteners, not at the intake of these sweeteners in other foods. Nowadays, low-calorie sweeteners are found in a <a href="http://uk.businessinsider.com/surprising-foods-that-artificial-sweeteners-are-hiding-in-2016-1/?r=US&IR=T/#okay-there-cant-be-an-artificial-sweetener-in-ketchup-right-reduced-sugar-just-means-its-not-as-sweet-as-regular-ketchup-right-21">range of foods</a>, including yogurts, sauces, baked goods and “health bars”. Many brands of toothpaste also contain them. It’s possible that the people in the observational studies who declared that they never drank beverages containing low-calorie sweeteners consumed these sweeteners in other foods.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/178476/original/file-20170717-6046-58md3e.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/178476/original/file-20170717-6046-58md3e.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/178476/original/file-20170717-6046-58md3e.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/178476/original/file-20170717-6046-58md3e.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/178476/original/file-20170717-6046-58md3e.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/178476/original/file-20170717-6046-58md3e.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/178476/original/file-20170717-6046-58md3e.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">Yogurts often contain low-calorie sweeteners.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/download/confirm/314117519?src=P128PSfoYKp0GeT3t8J7Hg-1-10&size=medium_jpg">meaofoto/Shutterstock</a></span>
</figcaption>
</figure>
<h2>How does it compare with sugar?</h2>
<p>Unfortunately, none of the studies in the review compared consuming low-calorie sweetened drinks with sugary drinks. What is clear from earlier studies is that there is a close parallel between the rise in sugar consumption and <a href="http://ajcn.nutrition.org/content/84/2/274.full.pdf+html%20and%20type%202%20diabetes">increases in global obesity</a>. And other studies have found that consuming sugar-sweetened beverages is associated with an increased risk of <a href="http://journals.lww.com/co-cardiology/Abstract/publishahead/Sugar_sweetened_beverages_and_cardiometabolic.99270.aspx">type 2 diabetes and coronary heart disease</a>, independent of weight. </p>
<p>It has become increasingly clear: sugar is <a href="https://www.theatlantic.com/magazine/archive/2017/01/the-sugar-wars/508751/">very bad</a> for your health. So it seems logical to assume that if high calorie sugar is replaced with low-calorie sweetener then we reduce the risk of weight gain, type 2 diabetes and heart disease. What this latest study suggests is that this may not be the case. </p>
<p>The evidence against low-calorie sweeteners may not be watertight, but, if the latest review is correct, it might be best if we avoided them. Maybe we’ll just have to wean ourselves off sweet-tasting foods altogether, regardless of what they’re sweetened with.</p><img src="https://counter.theconversation.com/content/81037/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Rachel Adams 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>The evidence against low-calorie sweeteners is mounting. But that doesn’t mean natural sugar is better.Rachel Adams, Senior Lecturer in Biomedical Science, Cardiff Metropolitan UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/758912017-04-18T06:08:46Z2017-04-18T06:08:46ZArtificial sweeteners are said to be ‘lite’ but they leave a heavy burden on your health<figure><img src="https://images.theconversation.com/files/165313/original/image-20170413-25886-1ucpien.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Diet drinks are even worse for our health than regular sugary sodas.</span> <span class="attribution"><a class="source" href="https://www.flickr.com/photos/tomhilton/29187714266">tomhilton/flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span></figcaption></figure><p>Diet soda drinkers, beware. Recent epidemiological <a href="https://www.ncbi.nlm.nih.gov/pubmed/27044603">studies</a> have confirmed that the sweeteners used in diet sodas and other lite drinks increase the risk of type 2 diabetes.</p>
<p>Often asymptomatic, type 2 diabetes is <a href="http://ceed-diabete.org/en/diabetes/diabetes-and-complications/type-2-diabetes/">the most common form of diabetes</a>, and is most often found among people who are overweight and sedentary. </p>
<p><a href="https://www.ncbi.nlm.nih.gov/pubmed/28214853">Just published research results out of France</a> show that people who “always or almost always” add sweeteners to their drinks – in sachet or tablet form – had an 83% higher risk of developing diabetes than those who use them “never or rarely”. </p>
<p><a href="https://www.cancer.org/cancer/cancer-causes/aspartame.html">Aspartame</a>, the most commonly used sweetener, and, more recently, <a href="https://authoritynutrition.com/sucralose-good-or-bad/">sucralose</a> (aka Splenda), have been used to replace <a href="https://theconversation.com/fact-or-fiction-is-sugar-addictive-73340">sugar</a> in so-called “diet” sodas for over 30 years. </p>
<figure class="align-left ">
<img alt="" src="https://images.theconversation.com/files/165494/original/image-20170417-25898-91ysdr.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/165494/original/image-20170417-25898-91ysdr.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=388&fit=crop&dpr=1 600w, https://images.theconversation.com/files/165494/original/image-20170417-25898-91ysdr.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=388&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/165494/original/image-20170417-25898-91ysdr.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=388&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/165494/original/image-20170417-25898-91ysdr.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=487&fit=crop&dpr=1 754w, https://images.theconversation.com/files/165494/original/image-20170417-25898-91ysdr.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=487&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/165494/original/image-20170417-25898-91ysdr.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=487&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Not so pretty in pink.</span>
<span class="attribution"><a class="source" href="https://flic.kr/p/bjLFrW">Fort Greene Focus/flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>Even though the quantity of artificial sweeteners in our <a href="https://theconversation.com/fr/topics/alimentation-21911">diet</a> has increased massively in recent years as industrial manufacturers add them with growing abandon to not just drinks but also cereals, biscuits, cakes, low-calorie yogurts and even certain medicines, reliable and precise data on their health impacts are rare. </p>
<p>Such products are marketed as low-calorie alternatives that are therefore healthy. This perception encourages consumers to overuse sweeteners to avoid putting on weight. But, even in moderation, these additives can have negative effects on health. </p>
<p>Today, sweeteners are increasingly controversial, and suspected of contributing to weight gain and being carcinogenic. </p>
<p>This has <a href="https://www.ncbi.nlm.nih.gov/pubmed/26199070">independent researchers</a> across the world seeking to measure their real effects on health, particularly their impact on metabolic diseases. </p>
<h2>Increase risk of diabetes and cancer</h2>
<p>Our team at France’s <a href="http://cesp.inserm.fr/">Centre for Research in Epidemiology and Population Health</a> at Inserm, has been contributing to this growing body of health knowledge since 2012 through a research program on the risk factors for <a href="http://www.ameli-sante.fr/diabete-de-type-2.html">type 2 diabetes</a>.</p>
<p>The program’s findings suggest that sugar substitutes should be treated with the utmost caution. In February, <a href="https://www.ncbi.nlm.nih.gov/pubmed/28214853">we published a study</a> showing that the risk of diabetes increases with the consumption of artificial sweeteners. We had already shown that <a href="https://www.ncbi.nlm.nih.gov/pubmed/?term=Consumption+of+artificially+and+sugar-sweetened+beverages+and+incident+type+2+diabetes+in+the+E3N-EPIC+Cohort.+The+American+journal+of+clinical+nutrition">this risk was higher with so-called “diet” drinks</a> than with regular sodas.</p>
<p><a href="https://www.ncbi.nlm.nih.gov/pubmed/28214853">Our research</a> is based on data from a cohort of nearly 100,000 French women in the Epidemiological Study of Women in National Education or <a href="http://www.e3n.fr">E3N</a>, one of the world’s few cohorts of this size.</p>
<p>This prospective cohort study has been monitoring the health of women who belong to the mutual health insurance company for French national education staff for the past 27 years. <a href="https://www.youtube.com/watch?v=qnofZ6efkOo">Initiated by epidemiologist Françoise Clavel-Chapelon</a>, the study aims to improve understanding of women’s health and their risks of developing chronic conditions, such as cancer or type 2 diabetes.</p>
<p>Participants have completed <a href="http://www.e3n.fr/images/Questionnaires_pdf/Questionnaire_8_alimentaire.pdf">detailed questionnaires</a> on their diets since 1993, giving full details of each food intake, including snacks and appetisers prior to the three main meals and evening snacks. This gives researchers precise <a href="http://www.e3n.fr/images/Questionnaires_pdf/Questionnaire_3_cahier_photos_BD.pdf">information, including pictures</a>, of both the foods and drinks consumed and the average nutritional intake for each woman. The study ended in 2007.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/165496/original/image-20170417-25865-1ayqmjn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/165496/original/image-20170417-25865-1ayqmjn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=335&fit=crop&dpr=1 600w, https://images.theconversation.com/files/165496/original/image-20170417-25865-1ayqmjn.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=335&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/165496/original/image-20170417-25865-1ayqmjn.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=335&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/165496/original/image-20170417-25865-1ayqmjn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=421&fit=crop&dpr=1 754w, https://images.theconversation.com/files/165496/original/image-20170417-25865-1ayqmjn.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=421&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/165496/original/image-20170417-25865-1ayqmjn.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=421&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Standard glasses used to estimate the quantities of sugary, sweetened and artificially sweetened beverages consumed.</span>
<span class="attribution"><a class="source" href="http://www.e3n.fr/images/Questionnaires_pdf/Questionnaire_3_cahier_photos_BD.pdf">G.Fagherazzi</a>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<h2>Want a soda? Avoid diet</h2>
<p>Studying this data in 2013, our team was able to demonstrate for the first time a higher risk of diabetes associated with diet drinks rather than with regular sodas.</p>
<p>Of the 66,118 women followed during this project, 1,369 were diagnosed with type 2 diabetes. Our team modelled the risk of developing the disease depending on consumption of three types of drinks: regular sodas, artificially sweetened sodas and 100% pure fruit juice. We took into account other factors such as physical activity, body mass index and family history.</p>
<p><a href="https://www.ncbi.nlm.nih.gov/pubmed/27044603">Other studies</a> had already shown an increased risk of diabetes associated with high consumption of soda in general. </p>
<p>This time, we managed to distinguish between them. For example, at 1.5 litres per week (the equivalent of a large bottle), the risk of diabetes was 60% higher with diet drinks than with regular sugary drinks. These results are all the more striking considering that people then drank less sugar-free sodas than we do today. The average back then was about 328 ml of sugary drinks each week (about a can), and 568 ml of “diet” drinks.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/165495/original/image-20170417-25875-1r46avu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/165495/original/image-20170417-25875-1r46avu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=310&fit=crop&dpr=1 600w, https://images.theconversation.com/files/165495/original/image-20170417-25875-1r46avu.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=310&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/165495/original/image-20170417-25875-1r46avu.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=310&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/165495/original/image-20170417-25875-1r46avu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=390&fit=crop&dpr=1 754w, https://images.theconversation.com/files/165495/original/image-20170417-25875-1r46avu.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=390&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/165495/original/image-20170417-25875-1r46avu.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=390&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">The solid line indicates type 2 diabetes risk according to the quantity consumed of: sugary drinks (left), sweetened drinks (centre), and fruit juice (right).</span>
<span class="attribution"><a class="source" href="http://ajcn.nutrition.org/content/97/3/517/F1.expansion.html">Guy Fagherazzi</a></span>
</figcaption>
</figure>
<p>Significantly, there was no increase in the risk of diabetes with 100% pure fruit juices, which are naturally sweetened products.</p>
<h2>Artificial sugar makes you feel hungry</h2>
<p>Recently, our team used the E3N study to look at women’s consumption of sweeteners in sachet or tablet form. <a href="https://www.ncbi.nlm.nih.gov/pubmed/28214853">In our latest study</a> we show that those who use them “always or almost always” had an 83% higher risk of developing diabetes than those who use them “never or rarely.” </p>
<p>Participants who used them regularly for more than ten years had a 110% higher risk than those who never or rarely used them, suggesting a cumulative effect over time.</p>
<p>The increase in risk persists when <a href="http://www.inserm.fr/dossiers-d-information/indice-de-masse-corporelle">body mass index</a> is taken into account, although it is slightly lower. It therefore appears that sweeteners have a direct effect on the risk of diabetes, even if being overweight is also a risk factor.</p>
<p>From a physiological point of view, the mechanism behind these results is still far from clear. One hypothesis is that people who consume a lot of sweeteners have a greater appetite for sugar, coupled with a tendency to overeat in general. </p>
<p>Sweeteners <a href="https://www.ncbi.nlm.nih.gov/pubmed/27085864">are thought to increase the feeling of hunger</a> or to activate the T1R2/T1R3 receptors, which detect a wide variety of chemically and structurally diverse sweet-tasting molecules, along the digestive tract. If that’s the case, obviously sweeteners will not produce the desired effect, namely staying slim.</p>
<p>Another hypothesis is that those who consume large amounts of sweeteners also produce less of the GLP-1 (Glucagon-Like Peptide-1) hormone, <a href="https://www.ncbi.nlm.nih.gov/pubmed/25828597">which promotes pancreatic insulin secretion</a>, and suffer more frequent deregulation of their glucose metabolism.</p>
<h2>Sweeteners can alter our gut microbiota</h2>
<p>Lastly, research on animals at the Weizmann Institute of Science in Israel <a href="http://www.jpost.com/Israel-News/Health/Artificial-sweeteners-could-actually-lead-to-diabetes-say-scientists-at-Weizmann-Institute-375668">has shown</a> that high consumption of certain sweeteners causes <a href="https://www.ncbi.nlm.nih.gov/pubmed/25231862">changes in the intestinal microbiota</a>. </p>
<p>We now know these microorganisms, which regulate digestive, metabolic, immune and neurological functions in the human body, to be important for health. Altering them is thought to lead to glucose intolerance and insulin resistance, a trigger for type 2 diabetes.</p>
<p>Whether people are trying to lose weight or avoid sugars, it’s time to convey a more accurate message about the benefits – or rather, the risks – of so-called “lite” foods.</p><img src="https://counter.theconversation.com/content/75891/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Dr Guy Fagherazzi 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>Artificial sweeteners used in diet sodas and other low-calorie foods can actually contribute to weight gain and type 2 diabetes. The more you use, the higher the risk.Dr Guy Fagherazzi, Chercheur en épidémiologie du diabète, UMR 1018, Inserm, Université Paris-SaclayLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/570032016-04-01T11:47:35Z2016-04-01T11:47:35ZWhy finding a real alternative to sugar is so difficult<figure><img src="https://images.theconversation.com/files/116777/original/image-20160330-28455-1j1phef.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Sweets for my sweets ...</span> <span class="attribution"><a class="source" href="http://www.shutterstock.com/cat.mhtml?lang=en&language=en&ref_site=photo&search_source=search_form&version=llv1&anyorall=all&safesearch=1&use_local_boost=1&autocomplete_id=&searchterm=spoonful%20of%20sugar&show_color_wheel=1&orient=&commercial_ok=&media_type=images&search_cat=&searchtermx=&photographer_name=&people_gender=&people_age=&people_ethnicity=&people_number=&color=&page=1&inline=237309733">Kozlenko</a></span></figcaption></figure><p>So much for the decades in which fats and oils were public enemy number one on our dinner plates. There is <a href="http://www.actiononsugar.org/index.html">more and more evidence</a> that sugar – or more precisely, carbohydrate – is behind our increasing rates of <a href="http://www.healthdata.org/news-release/nearly-one-third-world%E2%80%99s-population-obese-or-overweight-new-data-show">obesity</a> and <a href="https://www.sciencedaily.com/releases/2015/04/150402101410.htm">heart disease</a>. Even if the mechanisms by which this occurs are still not well defined, there are endless <a href="http://www.who.int/mediacentre/news/releases/2015/sugar-guideline/en/">calls for</a> reducing its quantities in the foods we eat. Most recently in the UK this led to the chancellor, George Osborne, <a href="https://theconversation.com/sorry-jamie-oliver-id-be-surprised-if-sugar-tax-helped-cut-obesity-56471">announcing</a> a tax on sugary soft drinks. </p>
<p>Had we ever come up with a proper substitute for sugar, of course, we wouldn’t need to have this debate. In <a href="https://theconversation.com/heres-what-happens-to-your-brain-when-you-give-up-sugar-for-lent-37745">our sweetness-addicted era</a>, it is one of science’s greatest challenges. So why has it eluded us for so long, and are we any closer to a solution?</p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/116984/original/image-20160331-31093-1gmtfqu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/116984/original/image-20160331-31093-1gmtfqu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/116984/original/image-20160331-31093-1gmtfqu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=587&fit=crop&dpr=1 600w, https://images.theconversation.com/files/116984/original/image-20160331-31093-1gmtfqu.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=587&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/116984/original/image-20160331-31093-1gmtfqu.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=587&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/116984/original/image-20160331-31093-1gmtfqu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=738&fit=crop&dpr=1 754w, https://images.theconversation.com/files/116984/original/image-20160331-31093-1gmtfqu.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=738&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/116984/original/image-20160331-31093-1gmtfqu.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=738&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Saccharine on sale.</span>
<span class="attribution"><a class="source" href="http://www.shutterstock.com/cat.mhtml?lang=en&language=en&ref_site=photo&search_source=search_form&version=llv1&anyorall=all&safesearch=1&use_local_boost=1&autocomplete_id=&searchterm=saccharine&show_color_wheel=1&orient=&commercial_ok=&media_type=images&search_cat=&searchtermx=&photographer_name=&people_gender=&people_age=&people_ethnicity=&people_number=&color=&page=1&inline=240640765">Lunasee Studios</a></span>
</figcaption>
</figure>
<p>Replacing the sweetness of sugar in foods is actually relatively straightforward. The first synthetic sweetener, saccharine, was <a href="http://www.todayifoundout.com/index.php/2014/05/saccharin-discovered-accident/">discovered accidentally</a> by a young Russian chemist named Constantin Fahlberg in 1879 while studying coal-tar derivatives, when he unknowingly got it on his hands and licked his fingers. Saccharine became widely used around World War I, when natural sugar was in short supply. In the 1960s scientists discovered several more artificial sweeteners in similarly serendipitous ways, including aspartame and acesulfame K.</p>
<p>As well as these discoveries, there are naturally occurring sweeteners that we have actually known about for much longer (see table below). The <a href="http://linguistics.byu.edu/classes/ling450ch/reports/Guarani1.html">Guarani</a> peoples of modern-day Brazil and Paraguay have been using the leaves of the <a href="https://theconversation.com/a-rose-by-any-other-name-the-low-down-on-healthy-coke-33552">stevia</a> plant as a sweetener for about 1,500 years. And the seeds of the West African katemfe fruit, which contain a sweet chemical called thaumatin, have been on our radar since the 19th century. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/116771/original/image-20160330-9712-1frvkxu.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/116771/original/image-20160330-9712-1frvkxu.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=185&fit=crop&dpr=1 600w, https://images.theconversation.com/files/116771/original/image-20160330-9712-1frvkxu.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=185&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/116771/original/image-20160330-9712-1frvkxu.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=185&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/116771/original/image-20160330-9712-1frvkxu.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=233&fit=crop&dpr=1 754w, https://images.theconversation.com/files/116771/original/image-20160330-9712-1frvkxu.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=233&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/116771/original/image-20160330-9712-1frvkxu.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=233&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">‘Sweetness’ is relative to sugar – stevia is 275 times as sweet.</span>
</figcaption>
</figure>
<h2>Sweet but sour</h2>
<p>Yet while we have plenty of options for sweetness, there are several difficulties associated with using non-sugar sweeteners in foods. There have been various cancer scares over the years, which have affected <a href="http://drrichswier.com/2015/05/25/fda-generated-stevia-myth/">stevia</a>, <a href="http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1637197/">saccharine</a> and <a href="http://www.mercola.com/article/aspartame/hidden_dangers.htm">aspartame</a>, among others. Some artificial sweeteners have <a href="http://www.nhs.uk/news/2014/09September/Pages/Do-artificial-sweeteners-raise-diabetes-risk.aspx">also been</a> linked to type 2 diabetes. </p>
<p>To compound this, governments class all non-sugar sweeteners as additives, which means they are assigned an E-number – even stevia and thaumatin. In an era where consumers have become increasingly wary of these numbers even when there aren’t specific health risks, manufacturers have been moving towards so-called “clean-label” products that are free of them. This puts these sweeteners at a disadvantage. </p>
<p>Aside from health and labelling, sugars have chemical functions in foods that make them difficult to replace. Sugar solutions freeze at a lower temperature than pure water, for instance. In products like ice cream, this is critical to maintaining a soft texture at freezer temperatures. </p>
<p>Sugars play an important role in giving products like bread, cakes and even wine their darker colour, through what chemists call <a href="http://www.scienceofcooking.com/browning_of_foods.htm">non-enzymatic browning reactions</a>. Artificial
sweeteners are not good at reproducing either of these. </p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/116781/original/image-20160330-28472-616nos.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/116781/original/image-20160330-28472-616nos.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/116781/original/image-20160330-28472-616nos.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=900&fit=crop&dpr=1 600w, https://images.theconversation.com/files/116781/original/image-20160330-28472-616nos.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=900&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/116781/original/image-20160330-28472-616nos.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=900&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/116781/original/image-20160330-28472-616nos.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1130&fit=crop&dpr=1 754w, https://images.theconversation.com/files/116781/original/image-20160330-28472-616nos.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1130&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/116781/original/image-20160330-28472-616nos.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1130&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">‘Mmmm aspartame.’</span>
<span class="attribution"><a class="source" href="http://www.shutterstock.com/pic-12164185/stock-photo-man-checking-food-labelling-on-supermarket-products.html?src=csl_recent_image-1">Monkey Business Images</a></span>
</figcaption>
</figure>
<p>Then there is aftertaste. This arises from the mechanism by which sweetness is detected in the taste buds. One problem is that the structural features of any sweet molecule that allow them to bind to the sweetness receptors on the tongue are <a href="http://www.sciencedirect.com/science/article/pii/S0092867403000710">similar to</a> the ones that bind to our bitterness receptors. This is why some sweeteners leave a bitter aftertaste, which is of course undesirable to some consumers. </p>
<p>But looking at the previous table again, for sweeteners that don’t have a bitter aftertaste there is another issue. Artificial sweeteners bind more strongly to the sweetness receptors and have a different and longer-lasting taste profile to sugar, and so are perceived as tasting different by consumers. </p>
<p>All in all, although non-sugar sweeteners are a multi-billion-pound industry, these drawbacks help to explain why they are nowhere near eclipsing sugar. In 2014 sugar (sucrose) <a href="http://www.preparedfoods.com/articles/114720-alternative-sweeteners-gain-12-share-of-734-billion-market">accounted for</a> 78% of all sweetener sales. Artificial sweeteners made up 8%, with acesulfame k the market leader. Natural alternatives like stevia, which was <a href="https://www.acefitness.org/certifiednewsarticle/1644/the-truth-about-stevia-the-so-called-quot-healthy/">banned</a> in the US and EU until fairly recently, made up 1%. (The rest of the market comprises everything from glucose to syrups). </p>
<h2>Where sweeteners go from here</h2>
<p>The cancer evidence against non-sugar sweeteners has turned out to be thinner than feared. <a href="http://www.cancerresearchuk.org/about-cancer/causes-of-cancer/diet-and-cancer/food-controversies#food_controversies1">Cancer Research UK</a> and the US <a href="http://www.cancer.gov/about-cancer/causes-prevention/risk/diet/artificial-sweeteners-fact-sheet">National Cancer Institute</a> both say there is no increased risk regarding artificial sweeteners. Stevia’s years in the wilderness were the result of an anonymous complaint about the cancer risks to the US authorities <a href="https://health.thefuntimesguide.com/2014/08/what-is-stevia.php">commonly thought</a> to have come from artificial-sweetener producers, but it has since been rehabilitated. As for type 2 diabetes, the <a href="http://www.nature.com/nature/journal/v514/n7521/full/nature13793.html">evidence linking it</a> to artificial sweeteners is <a href="http://nutritionreviews.oxfordjournals.org/content/71/7/433">inconclusive</a> and we need more research – so far it has all been done on animals. </p>
<p>On the physical issues, food scientists have had to think creatively. When it comes to texture, for instance, manufacturers add protein texturisers instead – <a href="http://www.clextral.com/food-feed-2/food/extured-protein/">soy</a>, for example. Or you can turn to other substances that have a similar effect as sugar on the freezing properties of water – the sugar alcohol erythritol is one option. </p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/116779/original/image-20160330-28443-133low5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/116779/original/image-20160330-28443-133low5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/116779/original/image-20160330-28443-133low5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=792&fit=crop&dpr=1 600w, https://images.theconversation.com/files/116779/original/image-20160330-28443-133low5.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=792&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/116779/original/image-20160330-28443-133low5.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=792&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/116779/original/image-20160330-28443-133low5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=995&fit=crop&dpr=1 754w, https://images.theconversation.com/files/116779/original/image-20160330-28443-133low5.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=995&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/116779/original/image-20160330-28443-133low5.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=995&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Stevia wonder?</span>
<span class="attribution"><a class="source" href="http://www.shutterstock.com/cat.mhtml?lang=en&language=en&ref_site=photo&search_source=search_form&version=llv1&anyorall=all&safesearch=1&use_local_boost=1&autocomplete_id=&searchterm=stevia&show_color_wheel=1&orient=&commercial_ok=&media_type=images&search_cat=&searchtermx=&photographer_name=&people_gender=&people_age=&people_ethnicity=&people_number=&color=&page=1&inline=99968267">Olivier le Moal</a></span>
</figcaption>
</figure>
<p>Manufacturers seek to overcome the aftertaste issue by mixing sweeteners. We perceive the aftertaste of different sweeteners over differing timescales, so one sweetener can be used to mask the aftertaste of a second. It is common to use stevia in combination with acesulfame K, for instance. </p>
<p>Another increasingly common ploy is to mix sugar and other sweeteners together. This helps explain why the use of non-sugar sweeteners in new product launches <a href="http://www.mintel.com/press-centre/food-and-drink/stevia-set-to-steal-intense-sweetener-market-share-by-2017-reports-mintel-and-leatherhead-food-research">rose from</a> 3.5% in 2009 to 5.5% in 2012. It also explains why stevia is rocketing. Food analysts Mintel and Leatherhead forecast it will have become the most widely used non-sugar sweetener by as early as next year. </p>
<p>In the absence of a Holy Grail for sugar replacement, this could be as good as it gets any time soon. No wonder the authorities are beginning to intervene to save us from our sweet tooth instead.</p><img src="https://counter.theconversation.com/content/57003/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Stephen Euston has received research funding from BBSRC, EPSRC, Innovate UK and EC Horizon2020, though the views in this piece are entirely his own. He is also a committee member of the Agri-Food group of the Society of Chemical Industry. </span></em></p>If only it were as simple as sweetness.Stephen Euston, Professor, Heriot-Watt UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/271802014-06-18T20:42:14Z2014-06-18T20:42:14ZWhy artificial sweetener can be dangerous<figure><img src="https://images.theconversation.com/files/51509/original/qvmq4989-1403070628.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">An excess of the one of the two amino acids in the artificial sweetener aspartame is a significant concern for people with phenylketonuria.</span> <span class="attribution"><a class="source" href="https://www.flickr.com/photos/wetterberg/3263493189">Hugo Wetterberg/Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by-nc/4.0/">CC BY-NC</a></span></figcaption></figure><p>When you buy a diet coke, or any other consumables containing the artificial sweetener aspartame, you’ll see a warning against consuming the product if you have phenylketonuria, an inherited metabolic disorder. </p>
<p>“Artificial” sweeteners, such as NutraSweet and Equal, are not saccharides – the simple carbohydrates we call sugars. Instead, the sweetener aspartame is a <a href="http://upload.wikimedia.org/wikipedia/commons/thumb/d/df/Methylcarboxylate_General_Structure.png/200px-Methylcarboxylate_General_Structure.png">methyl ester</a> comprising two joined amino acids: aspartic acid and phenylalanine (Phe) – this is important for later so keep it in mind. </p>
<p>The safety of aspartame for general consumption has attracted attention since its discovery in 1965, but there’s <a href="http://theconversation.com/sweet-news-no-evidence-that-artificial-sweetener-aspartames-bad-for-you-12608">no evidence</a> of association with adverse effects. The warning on products containing aspartame is specifically for those with the severe disorder known as phenylketonuria.</p>
<h2>Genetic basis</h2>
<p>For someone to have phenylketonuria, they have to inherit an incorrect copy of a gene involved in Phe breakdown from each parent. Typically, the parents of an affected person (known as carriers) each have one correct and one incorrect copy of the gene, so are unaffected themselves. </p>
<p>The main feature of the condition is the body’s inability to break down excess Phe (recall that this one of the two amino acids in aspartame). Now, this part gets complicated but stay with me.</p>
<p><a href="http://www.nlm.nih.gov/medlineplus/ency/article/002222.htm">Amino acids</a> can join linearly and fold into three dimensional shapes to construct functional proteins that perform a wide range of roles in our bodies. We produce some amino acids ourselves, but others, including Phe, must be obtained directly from our diet. </p>
<p>Amino acids can’t be stored by the body if we consume them in excess (unlike fats, for instance, and carbohydrates), so we need a constant supply. They also can’t be directly eliminated from the body, which means when excess amino acids are ingested, each type has to be broken down in a specific sequence of steps before excretion.</p>
<p>The first step in the degradation of Phe is its conversion to tyrosine, an amino acid important in neurotransmission (when signalling molecules from one neuron bind to and activate another). </p>
<p>This reaction requires an enzyme as well as the assistance of a sidekick (enzyme co-factor). The enzyme is produced through expression of its corresponding gene, and a problem arises when there are mutations in this gene. </p>
<p>There are <a href="http://theconversation.com/variomics-seeks-to-understand-what-makes-us-unique-12957">548 separate mutations</a> recorded for this gene that lead to the production of a differing enzyme, which means the body may not be able to break Phe down. </p>
<p>This differing enzyme has a reduced ability of perform the initial step in the breakdown of Phe, so the level of the amino acid in the body rises. And this has a toxic effect on neurons. Early detection of high Phe levels and intervention is vital to avoid severe mental disability. </p>
<h2>Diagnosis and treatment</h2>
<p>Phenylketonuria was first identified by Asbjorn Folling, a biochemist and physician, who noticed an unusual odour in the urine of some individuals with developmental delays. This smell was due to a molecule produced by the body when Phe accumulates.</p>
<p>A diagnostic test that worked reliably from around eight weeks of age (a drop of ferric copper added to a wet nappy would turn green in a positive test) was developed in the late 1950s. The problem was that, by this age, untreated babies had often already suffered brain damage. </p>
<p>Only a few years later, a new, more sensitive method permitted detection from three days after birth. The Guthrie or heel-prick test requires only a drop of blood from an infant. This blood is spotted on a paper disk and placed on growth media featuring bacteria unable to synthesise Phe. </p>
<p>Growing bacteria – because the Phe present in the blood spot supplements what they are unable to produce themselves – represents a positive result.</p>
<p>The <a href="http://en.wikipedia.org/wiki/Neonatal_heel_prick">heel-prick test</a> is widely performed as part of neonatal screening programs. But the diagnostic test now uses a technique called tandem <a href="http://en.wikipedia.org/wiki/Mass_spectrometry">mass spectrometry</a> and screening includes a wide range of conditions.</p>
<p>In the 1950s, a low-Phe diet was introduced for people with this severe metabolic disorder and it continues to be the predominant treatment. Since Phe is found in most food sources, the diet involves getting most energy intake from a formula instead of meals, supplemented by a small amount of foods low in protein (such as fruit and vegetables). </p>
<p>The restrictive nature of this diet means researchers are still looking for better treatments avenues. A <a href="http://www.sciencedirect.com/science/article/pii/S1096719212001473">synthetic form of the enzyme co-factor</a> is one option, as it an <a href="http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3205297/">enzyme able to break down Phe</a> and <a href="http://theconversation.com/explainer-what-is-gene-therapy-19883">gene therapy</a>.</p>
<p>But the reason why people with phenylketonuria can’t have aspartame-sweetened food is because, during digestion, it can separate into its component amino acids (aspartic acid and Phe). And this is bad news for people with the disorder.</p><img src="https://counter.theconversation.com/content/27180/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Rebecca LeBard 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>When you buy a diet coke, or any other consumables containing the artificial sweetener aspartame, you’ll see a warning against consuming the product if you have phenylketonuria, an inherited metabolic…Rebecca LeBard, Associate Lecturer, UNSW SydneyLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/126082013-04-10T20:42:30Z2013-04-10T20:42:30ZSweet news: No evidence that artificial sweetener aspartame’s bad for you<figure><img src="https://images.theconversation.com/files/22217/original/24f38dnp-1365479189.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Aspartame contains virtually no kilojoules in the minute quantity needed to sweeten a beverage or solid food.</span> <span class="attribution"><span class="source">Pascal/Flickr</span></span></figcaption></figure><p>Everyone who works in a chemistry laboratory knows that you don’t use your taste receptors to check if an unknown chemical is safe or deadly poisonous (or if you do, you may do it only once). But if this hadn’t inadvertently happened in one lab, the most commonly used artificial sweetener today may never have been discovered. </p>
<p>In 1965, a chemist working with amino acids (the building blocks of protein) created a new chemical by combining the amino acids aspartic acid and phenylalanine. He didn’t realise that some of this novel substance had spilled onto a piece of paper lying on the laboratory bench. The chemist licked his finger to pick up the paper and inadvertently transferred some of the chemical into his mouth.</p>
<p>Luckily, he lived to tell the tale. What he had to tell was extraordinary and completely unexpected. By combining two of the building blocks of protein (which has no sweetness), he had created a substance that was about 200 times as sweet as sugar!</p>
<p>Dubbed “aspartame”, the newly-created chemical was found to provide virtually no kilojoules in the minute quantity needed to sweeten a beverage or solid food.</p>
<p>After extensive safety testing, aspartame was approved for use in Europe and the United States in the 1980s. Its use as a sweetener in a range of foods at specified levels is <a href="http://www.foodstandards.gov.au/consumerinformation/aspartame.cfm">also permitted</a> in Australia and New Zealand.</p>
<p>Indeed, it is now the most widely used artificial sweetener in the world, and is sold in Australia most commonly under the brand names NutraSweet and Equal.</p>
<p><a href="http://tinyurl.com/bbnhc">Hoax claims</a> about aspartame have been circulating on the internet for many years. They suggest it was first developed as an ant poison, and that it is broken down in the body to release formaldehyde, leading to health problems such as severe seizures, brain damage, lupus and birth defects. No credible scientific evidence has ever been found for any of these claims.</p>
<p>Of more substance is the claim that artificial sweeteners, including aspartame, may be a cause of cancer. Rat studies have shown an association between the consumption of these sweeteners and cancer incidence.</p>
<p>But, as the <a href="http://www.wcrf.org/">World Cancer Research Fund</a> (WCRF) <a href="http://www.dietandcancerreport.org/cancer_resource_center/pr_full_report_english.php">pointed out in 2007</a>, the rat studies involved intakes “far greater than humans could consume in foods and drinks”. The WCRF concluded that “The evidence … does not suggest that chemical sweeteners have a detectable effect on the risk of any cancer.”</p>
<p>Another <a href="http://informahealthcare.com/doi/abs/10.1080/10408440701516184">comprehensive review</a> of the safety of aspartame, also published in 2007, came to a similar conclusion: “The weight of existing evidence is that aspartame is safe at current levels of consumption as a non‑nutritive sweetener.”</p>
<p>In 2010, two studies reported possible associations between aspartame and a slight increase in adverse health outcomes. After carefully reviewing these studies the <a href="http://www.efsa.europa.eu/">European Food Standards Agency</a> (EFSA) <a href="http://www.efsa.europa.eu/en/press/news/ans110228.htm">concluded that these studies</a> “do not give reason to reconsider previous safety assessments of aspartame …”</p>
<p>But taking an appropriately cautious approach, the report also stated that “… the EFSA will continue monitoring the scientific literature in order to identify new scientific evidence for sweeteners that may indicate a possible risk for human health or which may otherwise affect the safety assessment of these food additives.”</p>
<p>The <a href="http://www.efsa.europa.eu/en/supporting/pub/399e.htm">most recent (March 2013) review</a> of the literature by the EFSA concludes that “There is no consistent evidence that aspartame has adverse effects, either in healthy individuals or in potentially susceptible groups …”</p>
<p>The <a href="http://www.andjrnl.org/article/S2212-2672(12)00325-5/">2012 position paper</a> of the US <a href="http://www.eatright.org/public/default.aspx">Academy of Nutrition and Dietetics</a> also endorses the safety of aspartame by stating that “… consumers can safely enjoy a range of nutritive sweeteners and non-nutritive sweeteners (NNS).” Aspartame is included in the seven non-nutritive sweeteners that are approved for use.</p>
<p>The position paper also points out that the estimated safe level of daily intake of aspartame over a lifetime is 50 milligrams per kilogram of body weight. With typical intakes estimated to be in the range 0.2 to 4.1 mg/kg, the rate of consumption of aspartame by virtually everyone is likely to be less than 10% of the maximum recommended level.</p>
<p>But there is one potential adverse health effect associated with the use of aspartame – a metabolic genetic condition called phenylketonuria (a mutation that makes an enzyme non-functional) affects about one person in 10,000. People with phenylketonuria cannot metabolise phenylalanine (which, you will recall, is one of the two protein building blocks that make up aspartame), so those people need to minimise intake of all sources of phenylalanine, including aspartame.</p>
<p>So, can I put my hand on my heart and swear that aspartame is safe for everyone other than people with phenylketonuria?</p>
<p>No, I can’t. Still, based on the evidence currently available, if I wanted to reduce my sugar intake but still enjoy sweetened tea or coffee, I would have no hesitation in using aspartame (or any of the other approved non-nutritive sweeteners).</p><img src="https://counter.theconversation.com/content/12608/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Chris Forbes-Ewan received funding from the National Health and Medical Research Council in 2006 for his contribution to the development of Nutrient Reference Values for Australia and New Zealand. His contribution was in the area of estimated energy requirements.
</span></em></p>Everyone who works in a chemistry laboratory knows that you don’t use your taste receptors to check if an unknown chemical is safe or deadly poisonous (or if you do, you may do it only once). But if this…Chris Forbes-Ewan, Senior Nutritionist, Defence Science and Technology OrganisationLicensed as Creative Commons – attribution, no derivatives.