tag:theconversation.com,2011:/ca-fr/topics/obesity-wars-16403/articlesObesity wars – La Conversation2020-09-15T11:39:02Ztag:theconversation.com,2011:article/1460312020-09-15T11:39:02Z2020-09-15T11:39:02ZGovernments set the rules – so they shouldn’t blame us for not behaving better<figure><img src="https://images.theconversation.com/files/357669/original/file-20200911-20-1wtmtw6.jpg?ixlib=rb-1.1.0&rect=152%2C71%2C5748%2C3916&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Bad food: it's addictive and cheaper. </span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/assortment-unhealthy-products-thats-bad-figure-573417277">Ekaterina Markelova/Shutterstock</a></span></figcaption></figure><p>Under <a href="https://www.tai.org.au/sites/default/files/P894%20Grounded%20-%20Aviation%20Emissions%20during%20Covid-19%20%5BWEB%5D_0.pdf">some estimates</a>, airplane emissions could be down by almost 40% in 2020 because of COVID-19 lockdowns. </p>
<p>We’ve been told not to fly so much for years by campaigners, researchers, even governments – that it’s our responsibility to reduce carbon emissions. Until governments prevented us from travelling to stop the spread of the virus, we’ve tended to ignore all this advice. </p>
<p>At the same time, our governments have provided incentives to fly. International aviation fuel tax exemption is estimated at around <a href="https://www.greenaironline.com/news.php?viewStory=2070">US$65 billion a year</a>, keeping the cost of air travel down and inflating demand. This is one example of how government policies encourage us to do one thing, even as we’re being told it’s our responsibility to behave differently.</p>
<p>My recent book examines <a href="https://bristoluniversitypress.co.uk/its-the-government-stupid">how governments continually blame</a> citizens for social outcomes which are the result of their own policies. Governments use the cult of personal responsibility to blame each of us for the way society is, when they are the ones setting the incentives for our behaviour.</p>
<p>Of course, people must take responsibility for the choices they make from their menu of opportunities. However, that menu, and the reasonableness of different alternatives on it, is set by society – and government is the major agent in society. </p>
<h2>Gun crime</h2>
<p>Take gun deaths. In the US, the massive gun-related death toll is directly attributable to the nature of gun regulations. The issue is not whether or not to ban guns, but the type of regulations restricting their sale and use. Gun regulations vary across countries, but <a href="https://bristoluniversitypress.co.uk/its-the-government-stupid">my research highlights</a> how tighter gun rules reduce death and injury rates. </p>
<p>Those who defend the US’s current lax gun regulations on the basis of constitutional rights, must take responsibility for the consequences of that defence. They must admit that the gun-related murder toll of more than <a href="https://www.pewresearch.org/fact-tank/2019/08/16/what-the-data-says-about-gun-deaths-in-the-u-s/">14,500</a> in 2017 is an acceptable rate. If they want keep current regulations, they need to take responsibility for the consequences of doing so, even after tragic mass shootings.</p>
<h2>Hooked on bad food</h2>
<p>Obesity, a growing health problem across the world, is another example. The British prime minister, Boris Johnson, <a href="https://www.theguardian.com/society/2020/jul/11/no-10-plans-weight-loss-drive-to-ready-uk-for-expected-covid-19-second-wave">announced another government initiative</a> on the issue in July. Like previous initiatives, it will be directed at personal behaviour giving advice about healthy food and exercise. While the food industry has been given calorie-reduction guidelines, <a href="https://www.gov.uk/government/news/new-voluntary-calorie-guidelines-to-help-industry-tackle-obesity">they are voluntary</a>, and the government has not stepped into regulate food manufacturing. </p>
<p>Almost 30% of the British population is <a href="https://commonslibrary.parliament.uk/research-briefings/sn03336/">deemed obese</a> and another 35% overweight. Britons eat too many refined grains, fats and sugars, especially in the form of sugar-sweetened beverages. People eat these highly processed, highly calorific products because they are cheap and tasty. </p>
<p>Countries around the world are beginning to respond to reducing obesity. <a href="https://www.diabetes.co.uk/food/trans-fats.html">Trans fats are banned in several countries</a>, but not the UK. All the UK has done is urge food manufacturers not to use trans fats, but it’s unclear whether they have been reduced to any great extent in British food. </p>
<p>Sugar is <a href="https://www.fabresearch.org/viewItem.php?id=9685">highly addictive</a>. We cannot blame food manufacturers for providing addictive food products – they operate in a competitive business. But it’s government’s fault for allowing it. </p>
<p>The <a href="https://www.lshtm.ac.uk/research/research-action/features/uk-sugar-tax-will-it-work">UK has introduced a sugar tax,</a> but still allows many sugar-free drinks to contain artificial sweeteners, which also <a href="https://www.nhs.uk/news/food-and-diet/soft-drinks-including-sugar-free-versions-linked-earlier-death/">affect people’s health</a>. </p>
<p>By failing to act, the government is responsible for creating circumstances that make it difficult for many people to make choices that will <a href="https://www.bmj.com/content/346/bmj.e7492">benefit their health</a>.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/child-obesity-is-linked-to-deprivation-so-why-do-poor-parents-still-cop-the-blame-106954">Child obesity is linked to deprivation, so why do poor parents still cop the blame?</a>
</strong>
</em>
</p>
<hr>
<h2>Gambling and drugs</h2>
<p>Gambling and recreational drugs are rather different to food when it comes to responsibility. Governments around the world have become less paternalistic in gambling but more so in drug use over the past century. </p>
<p>Gambling regulations have been eased in most European countries, the UK and Australia over the past 30 years. The bulk of research and legislative effort goes into helping problem gamblers who are already addicted. These problems emerge, however, because governments allow the industry to hook people in, notably with electronic gambling machines, which create addiction by <a href="https://mitpress.mit.edu/books/midbrain-mutiny">disrupting the neural reward centres</a> of those most subject to addiction.</p>
<p>Many governments have decided, however, that people cannot take responsibility for recreational drugs. Many people take recreational drugs <a href="https://books.google.co.uk/books/about/Legalising_Drugs.html?id=5gBpDwAAQBAJ&source=kp_book_description&redir_esc=y">without forming life-destroying addictions</a> and in fact more people die from <a href="https://www.drugfreeworld.org/course/lesson/the-truth-about-prescription-drugs/abuse-international-statistics.html">misuing prescription drugs</a> that recreational ones. Legalisation that regulates recreational drug use – which has been introduced in recent years in countries such as <a href="https://www.bbc.co.uk/news/world-us-canada-45806255">Canada</a> and <a href="https://pubmed.ncbi.nlm.nih.gov/22212070/">Portugal</a> – could be a far more welfare-enhancing policy than outright bans.</p>
<p>Governments blame citizens for their own policy failures far too often. It’s time to stop blaming people for being homeless, not being able to find a job, for being overweight or for the failing environment. Instead, politicians must take responsibility for the social and environmental problems we face.</p>
<p>
<section class="inline-content">
<img src="https://images.theconversation.com/files/249586/original/file-20181210-76983-1azl8ax.png?h=128">
<div>
<header>Keith Dowding is the author of:</header>
<p><a href="https://bristoluniversitypress.co.uk/its-the-government-stupid">It’s the Government, Stupid: How Governments Blame Citizens for Their Own Policies.</a></p>
<footer>Bristol University Press provides funding as a content partner of The Conversation UK</footer>
</div>
</section>
</p><img src="https://counter.theconversation.com/content/146031/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Keith Dowding 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>Governments often blame citizens for social outcomes which are the result of their own policies.Keith Dowding, Distinguished Professor of Political Science and Political Philosophy, Australian National UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/945202018-04-06T11:45:32Z2018-04-06T11:45:32ZSugar tax: what you need to know<figure><img src="https://images.theconversation.com/files/213406/original/file-20180405-189830-1rlytgw.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/success?src=GG3uJv9gEpsmlHGEoz9sdA-1-8">shutterstock</a></span></figcaption></figure><p>If you like swigging sugary drinks, you might get a bit of a surprise next time you go to buy one, as a so-called <a href="http://www.bbc.co.uk/news/health-43414777">sugar tax</a> has now come into force in the UK. </p>
<p>From now on, drinks with a sugar content of more than 5g per 100ml will be taxed 18p per litre and 24p for drinks with 8g or more. It’s hoped the tax will help to reduce sugar intake, as scientists have shown that <a href="http://care.diabetesjournals.org/content/33/11/2477.long">sugary drinks lead to weight gain</a> and diabetes. <a href="https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/613532/obes-phys-acti-diet-eng-2017-rep.pdf">Figures show</a> that 58% of women, 68% of men and 34% of 10- to 11-year-olds in the UK are classed as overweight or obese. </p>
<p>Of course, a tax alone is not going to solve the obesity problem overnight. Sugary drinks may be a leading source of sugar in <a href="https://www.gov.uk/government/news/phe-publishes-latest-data-on-nations-diet">the UK diet</a>, but they are not the only contributor to obesity. So while we are not going to see obesity prevalence crashing down anytime soon, what taxes can do is contribute to change. </p>
<h2>How to reduce sugar</h2>
<p>The UK sugar tax aims to incentivise sugar reduction in drinks. Because it is imposed on drinks over a certain sugar threshold, manufacturers have the option of lowering sugar levels to avoid the tax. This way, the government is sending a clear message to the industry: get your act together and get sugar down. </p>
<p>On this measure of success, we don’t have to wait for the tax to be implemented to know that it has had an effect. According to the the UK Treasury, over 50% of soft drinks manufacturers (including retailer own-brands) <a href="https://www.gov.uk/government/news/soft-drinks-industry-levy-comes-into-effect">have already reduced sugar levels</a>, responding to the stick of legislation. So much so, in fact, that the Treasury has <a href="https://www.gov.uk/government/news/soft-drinks-industry-levy-comes-into-effect">downgraded its forecast</a> of how much money the levy will bring in – still standing at an impressive £240m. </p>
<p>The taxes will also make a contribution to the funding of programmes designed to reduce obesity. Such “earmarking” of taxes is relatively rare, but in the UK the tax was introduced in the <a href="https://www.gov.uk/government/publications/budget-2016-documents/budget-2016">March 2016 budget</a> with the explicit goal to “fund a doubling of the primary schools sports premium”.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/213408/original/file-20180405-189821-1pusfvs.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/213408/original/file-20180405-189821-1pusfvs.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=381&fit=crop&dpr=1 600w, https://images.theconversation.com/files/213408/original/file-20180405-189821-1pusfvs.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=381&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/213408/original/file-20180405-189821-1pusfvs.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=381&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/213408/original/file-20180405-189821-1pusfvs.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=479&fit=crop&dpr=1 754w, https://images.theconversation.com/files/213408/original/file-20180405-189821-1pusfvs.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=479&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/213408/original/file-20180405-189821-1pusfvs.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=479&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Theoretically, a 1.75 litre bottle of cola bought from a supermarket could increase in price by about 25%.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/download/success?src=GG3uJv9gEpsmlHGEoz9sdA-1-16">Shutterstock</a></span>
</figcaption>
</figure>
<p>We know this approach is workable. In 2015, Jamie Oliver voluntarily imposed a 10p extra <a href="http://jech.bmj.com/content/71/11/1107">charge on the sugary drinks</a> served in his restaurants, encouraging others to do the same. The proceeds were donated to The <a href="http://www.childrenshealthfund.org.uk/about/">Children’s Health Fund</a>. In the two and a half years since, the fund has given away £162,000 in grants to improve child health. And <a href="https://www.sustainweb.org/news/mar18_school_fountains/">according to Sustain</a> – the NGO that manages the fund – 146,000 children have benefited from improved access to drinking water, as a result of the extra charge.</p>
<h2>Will it change what people buy?</h2>
<p>The UK government has not made changing people’s dietary habits an explicit aim of the tax. But evidence from elsewhere does suggest people buy less when a tax comes into force. For example, <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5442881/">in Mexico</a> – which introduced a one peso per litre excise tax on sugary drinks in 2014 – purchases of taxed drinks fell by almost 8% in the following two years. Larger decreases were seen in households at the lowest socioeconomic level. And people also bought more of the untaxed drinks – notably water. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/what-the-world-can-learn-from-mexicos-tax-on-sugar-sweetened-drinks-56696">What the world can learn from Mexico's tax on sugar-sweetened drinks</a>
</strong>
</em>
</p>
<hr>
<p>In the Mexico case, however, we don’t actually know if people started buying fewer sugary drinks because of the price hike, or because of another reason. This is because <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5442881/">the data</a> simply measures the decline after the tax, not why the decline is happening. So while prices are likely to have a played a role, there could be <a href="https://www.sciencedirect.com/science/article/pii/S0306919217308837">another mechanism</a> at work. It could be, for example, that the tax started a conversation, raised awareness, got the industry talking about what it would do in response, and stimulated other actions to reduce consumption. </p>
<h2>The lasting measure of success</h2>
<p>Getting people talking, even arguing, about the tax is also an important part in all of this. Is it fair, as it affects people who are poor more than the rich? Why do we need what is essentially a punitive measure to get industry to act? If we are against the idea, then what else would work better and can we prove it?</p>
<p>These questions are important because it’s when these conversations percolate through society, that norms can change. Less so-called nanny statism and more people working it out for themselves. Working out, perhaps, that producing and consuming a lot of sugary drinks is not normal at all, but something weird that should be relegated to the past. </p>
<p>An important measure of the success of the <a href="https://www.gov.uk/guidance/check-if-your-drink-is-liable-for-the-soft-drinks-industry-levy">Soft Drinks Industry Levy</a>, then, will be if it contributes to changing these norms – in industry and society. And if it does, it will help to contribute towards a healthier society and healthier people.</p><img src="https://counter.theconversation.com/content/94520/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Corinna Hawkes receives funding from the UK Department of Health as co-investigator on the Obesity Policy Research Unit.
She is on the Future of Food Advisory panel convened by Dave Lewis, CEO of Tesco.</span></em></p>Why you might soon be paying more for your favourite sugary drink.Corinna Hawkes, Professor of Food Policy, City, University of LondonLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/737762017-04-18T15:19:52Z2017-04-18T15:19:52ZSouth Africa needs more than a sugar tax to get to the bottom of obesity<figure><img src="https://images.theconversation.com/files/164297/original/image-20170406-16660-1apadzq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">People are leading more sedentary lifestyles and eating calorie dense foods fuelling obesity.</span> <span class="attribution"><span class="source">Shutterstock</span></span></figcaption></figure><p>South Africa has been wrapped up in public and parliamentary debates on the value of South Africa’s proposed sugar tax. These highlight that the growing obesity epidemic has been fuelled by people consuming high levels of sugar. </p>
<p>Obesity shortens a person’s lifespan and affects their quality of life. It leads to lifestyle diseases that result in among others strokes, blindness, amputations and kidney failure.</p>
<p>Obesity has become a global epidemic with more than <a href="http://www.who.int/mediacentre/factsheets/fs311/en/">600 million adults</a> worldwide classified as obese. The US leads the pack with a 34% obesity prevalence, followed by Mexico (30%) and New Zealand (about 26%). </p>
<p>In Africa, the World Health Organisation reports that South Africa has the highest obesity levels with 26.8% of people classified as obese. Seychelles has a 26.3% obese population while Botswana follows closely with 22.4%.</p>
<p>In South Africa obesity related lifestyle diseases rival HIV/AIDS and TB in terms of their impact. Research shows that chronic diseases result in one death every hour. About 40% of women and 11% of men suffer from obesity in the country. And 25% of teenage girls in rural South Africa are overweight or obese.</p>
<p>But blaming sugar for obesity neglects the many factors that are at play in this complex health issue.</p>
<p>Global studies show there are several other factors responsible for someone developing obesity. These include <a href="http://www.obesity.ulaval.ca/obesity/generalities/genetic.php">genetic links</a>, <a href="http://obesity.ygoy.com/environment-causes-obesity/">lifestyle changes</a>, <a href="http://healthyeating.sfgate.com/caloriedense-vs-nutrientdense-food-5391.html">calorie-dense diets</a>, <a href="https://www.hsph.harvard.edu/nutritionsource/sleep/">sleep deprivation</a> and <a href="https://www.theatlantic.com/health/archive/2015/12/sexual-abuse-victims-obesity/420186/">psychological problems</a>. </p>
<p>South Africa would need to investigate these links as part of its plan to tackle skyrocketing obesity rates. </p>
<h2>Genetic factors</h2>
<p>Scientists have established a genetic basis for obesity but defining the genetic contribution is still a challenge. Bio-medical research has made some headway.</p>
<p>Global <a href="https://academic.oup.com/epirev/article/29/1/49/437222/Genetic-Epidemiology-of-Obesity">research</a> has shown that some populations have a <a href="http://www.nature.com/nrg/journal/v10/n7/full/nrg2594.html">genetic predisposition</a> to obesity. For example, studies show that in the US and Europe, some populations are genetically prone to <a href="https://ghr.nlm.nih.gov/condition/bardet-biedl-syndrome#statistics">Bardet-Biedl syndrome</a>.
People who have this condition have <a href="http://www.webmd.com/children/bardet-biedl-syndrome">disproportionately distributed</a> fat on their abdomens and chests rather than their arms and legs. </p>
<p>Similarly <a href="https://ghr.nlm.nih.gov/condition/prader-willi-syndrome">Prader-Willi syndrome</a> – a complex genetic condition where people develop an insatiable appetite, which leads to chronic overeating and obesity – affects an estimated 1 in 10,000 to 30,000 people worldwide.</p>
<p>But studies into specific conditions in Africa are rare. And more generally, there have been limited genome-wide association studies on African populations. </p>
<h2>Technology and lifestyle changes</h2>
<p>As the world moves toward an information based economy, adults and children have increased the amount of time they spend on mobile phones, watching TV and on computers or tablets – taking sedentary lifestyles to a new level.</p>
<p>For children this shift means they have little time for unstructured play or physical activity – and it directly links to an increase in chronic, non-communicable diseases.</p>
<p>According to a <a href="http://www.milkeninstitute.org/publications/view/531">study</a> by the Milken Institute in the US, every 10% investment in information and communication technology results in a one percent increase in obesity. </p>
<p>In the US, for example, according to research, children spend between <a href="http://www.sciencedirect.com/science/article/pii/S1555415516305050">five and 10 and a half hours daily</a> sedentary watching TV, playing video games and engaging with their iPods, tablets, smartphones and social media. As a result, 17% of the paediatric population in the US are obese. </p>
<h2>Calorie-dense diets</h2>
<p>In addition to technology, <a href="http://ajcn.nutrition.org/content/82/1/265S.full">people’s daily diets</a> have seen massive changes in the past few decades. Energy dense foods have more calories than nutrients. A high intake of empty calorie foods may cause people to gain weight, especially if they take in more calories than they burn. </p>
<p>Many working parents have to make long commutes to work and rely on convenience foods packed with salt, sugar and fat instead of home cooked meals made from fresh ingredients. Many of these products also contain high levels of gluten.</p>
<p>A growing body of research links gluten – a protein found in grains such as wheat – with potentially harmful effects on gut health, inflammation, fat regulation, metabolism and fat storage. </p>
<p>In a <a href="http://www.naturalnews.com/038699_gluten_weight_gain_wheat_belly.html">Brazilian study</a> researchers link gluten to obesity. Researchers <a href="http://www.huffingtonpost.com/dr-mark-hyman/wheat-gluten_b_1274872.html">argue</a> the modern way wheat products are processed means they contain amylopectin and gluten additives that are fattening, inflammatory and addictive. These drive obesity, diabetes, heart disease, cancer and dementia.</p>
<h2>Sleep deprivation</h2>
<p>The prevalence of obesity in the last several decades has been paralleled by a trend of reduced sleep in adults and children. </p>
<p>Worldwide, <a href="http://blogs.webmd.com/sleep-disorders/2010/10/sleep-deprivation-around-the-world.html">85%</a> of people suffer from insomnia. Too little sleep disrupts the normal functioning of our bodies. This includes the hormones that regulate hunger and satiety -– which can result in overeating.</p>
<p>Chronic, even partial sleep loss, <a href="https://www.purelyb.com/be-mindful/get-informed?view=entry&id=297">affects hormones</a> including those which regulate hunger and satiety-related hormones such as ghrelin and leptin. </p>
<p>There’s a close link between how much people sleep and how much they weigh. A group of researchers <a href="http://onlinelibrary.wiley.com/doi/10.1038/oby.2007.118/full">studied</a> about 60,000 women for 16 years, asking them about their weight, sleep habits, diet, and other aspects of their lifestyle. </p>
<p>At the start of the study, none of the women were obese. After 16 years, those who slept five hours or less each night had a 15% higher risk of becoming obese compared to women who slept seven hours each night. </p>
<p><a href="https://www.hsph.harvard.edu/obesity-prevention-source/obesity-causes/sleep-and-obesity/">Studies</a> spanning five continents have looked at the link between sleep duration and obesity in children. Most of these studies have found a <a href="http://pediatrics.aappublications.org/content/pediatrics/133/6/1013.full.pdf">convincing association</a> between too little sleep and increased weight.</p>
<h2>The psychology around obesity</h2>
<p>A <a href="https://www.sciencedaily.com/releases/2014/09/140902092947.htm">meta-analysis</a> carried out on previous childhood sexual trauma studies, which included a total of 112,000 participants has shown that being subjected to abuse during childhood entails a markedly increased risk of developing obesity as an adult.</p>
<p>Such <a href="http://onlinelibrary.wiley.com/doi/10.1111/obr.12216/full">studies</a> have shown that victims of childhood sexual abuse are far more likely to become obese adults.</p>
<p>And <a href="http://www.iowaaces360.org/ace-study.html">new research</a> shows that early trauma is so damaging that it can disrupt a person’s entire psychology and metabolism. This also links to stigma. For example, local researchers found that the stigma attached to HIV/AIDS and weight loss or “thinness” could be fuelling the obesity epidemic among some women. <a href="https://www.hindawi.com/journals/jtm/2009/145891/">Studies in Sub-Saharan Africa</a> have shown that being thin is associated with being HIV positive. </p>
<p>What this adds up to is that if the South African government goes ahead with its plans to implement the sugar tax, it also has a responsibility to fund research into obesity patterns in the country as well as educate consumers and create supportive community environments to assist people to make healthier lifestyle choices.</p><img src="https://counter.theconversation.com/content/73776/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Nellie Myburgh receives funding from the Bill and Melinda Gates Foundation. </span></em></p>South Africa has the highest obesity levels in Africa but blaming sugar neglects the many factors at play in this complex health issue.Nellie Myburgh, Senior researcher at the Wits Health Consortium, University of the WitwatersrandLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/408222015-04-27T19:48:43Z2015-04-27T19:48:43ZObesity wars revisited: is it the meat or the motion?<figure><img src="https://images.theconversation.com/files/79409/original/image-20150427-23954-f4yt7n.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Researchers appear to be stuck in a tug-of-war over the causes of the current levels of obesity.</span> <span class="attribution"><a class="source" href="https://www.flickr.com/photos/flintman45/7991164985">lee roberts/Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span></figcaption></figure><p>Obesity researchers have been in a tug-of-war for decades now — is obesity really that bad for us, or isn’t it? Is it getting worse or better? Is it a matter for individual choice or collective action? And in the past week, there’s been a new offensive in the obesity wars.</p>
<p>The authors of a <a href="http://bjsm.bmj.com/content/early/2015/04/21/bjsports-2015-094911.full.pdf+html">rather incendiary editorial</a> published in the British Journal of Sports Medicine started this round with the claim that the main cause of obesity was overeating, particularly eating too much refined carbohydrate. And, they added, physical activity plays little, if any role. </p>
<p>“You can’t outrun a bad diet,” they write, specifically attacking Coca-Cola for its line “all calories count”, which they say suggests “it is ok to consume their drinks as long as you exercise.” </p>
<p>What silence followed didn’t prevail for long. <a href="https://gebn.org/news/home/item/26-physical-activity-is-not-a-myth">In a typically blistering response</a>, Dr Steven Blair, writing on behalf of the Global Energy Balance Network which is partly funded by Coca-Cola, attacked the authors for flawed research and failure to disclose commercial interests.</p>
<p>The debate has put a spark to the tinder of a debate that’s been smoking for several years. Blair exchanged fire with other research luminaries <a href="http://ije.oxfordjournals.org/content/42/6/1836.extract">in a 2013 skirmish</a> when two US researchers claimed that public policy around obesity should have just one focus: controlling the food environment.</p>
<p>This debate is the obesity world’s equivalent of the Game of Thrones. It has everything: it pits armies of dietitians against physical activity researchers; it’s rich with aggressive accusations of pandering to base commercial interests; and it launches bombshells of academic delinquency if not outright fraud.</p>
<h2>But first…</h2>
<p>So where does the truth lie? Well, I shall reveal all. But first, let’s get one thing out of the way, because I can already hear the thunder of ad hominem attacks on the horizon. </p>
<p>I received direct funding, albeit quite modest, from Coca-Cola in 2014 to present at a conference in Dubai on physical activity. They also once sent me a very nice basket of fruit for a talk I gave to their executives. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/79412/original/image-20150427-23932-bsltdq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/79412/original/image-20150427-23932-bsltdq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=435&fit=crop&dpr=1 600w, https://images.theconversation.com/files/79412/original/image-20150427-23932-bsltdq.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=435&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/79412/original/image-20150427-23932-bsltdq.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=435&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/79412/original/image-20150427-23932-bsltdq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=546&fit=crop&dpr=1 754w, https://images.theconversation.com/files/79412/original/image-20150427-23932-bsltdq.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=546&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/79412/original/image-20150427-23932-bsltdq.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=546&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">We know that physical activity promotes weight loss but it’s nowhere near as effective as diet.</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/pagedooley/4663395686">Kevin Dooley</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<p>And I’ve been involved in international projects led by groups that receive funding from the Coca-Cola company, but for which neither I nor my institution have received direct funding. </p>
<p>I have also received funding from the National Health and Medical Research Council, the Australian Research Council, Beyond Blue, the Department of Defence, the National Heart Foundation and Healthway, among many other government bodies and non-government organisations supporting research. And I receive royalty payments from UNSW Press, bless them.</p>
<h2>The two sides</h2>
<p>Fire from the opposed camps — diet versus exercise — has been focused on two key strategic points: whether physical activity promotes weight loss; and whether the obesity epidemic is almost entirely due to increases in energy intake rather than decreases in energy expenditure. </p>
<p>Let’s take these one at a time.</p>
<p>Does physical activity promote weight loss? The short answer is that it can, but you need to do an awful lot of physical activity. And it’s nowhere near as effective as diet. It appears to be easier to diet ourselves thin than to exercise ourselves thin. </p>
<p>The <a href="http://europepmc.org/abstract/med/19127177">American College of Sports Medicine</a> recommends a minimum of 250 minutes a week of exercise for long-term weight loss. And 150 to 250 minutes a week to prevent weight gain. But diet consistently outperforms exercise for weight loss, while diet plus exercise outperforms both. </p>
<p><a href="http://www.indiana.edu/%7Ek562/articles/obesity/review%20Miller%201997.pdf">A meta-analysis that looked at the previous 25 years of research</a> found dietary interventions in obese participants resulted in a loss of five-and-a-half kilograms of fat, exercise in just over two kilograms, and diet plus exercise in almost eight kilograms. It seems it’s a little easier to overcome our gluttony than our sloth.</p>
<p>But this doesn’t mean that exercise is a waste of time for weight loss: <a href="http://bmjopen.bmj.com/content/4/12/e005927.full">cross-sectional studies</a> consistently show that physically active people are leaner, and several <a href="http://jama.jamanetwork.com/article.aspx?articleid=187071">longitudinal studies</a> have shown that people who remain active have a lower risk of gaining fat.</p>
<p>So, is the obesity epidemic due to people eating more or exercising less? People don’t seem to be exercising more or less than they used to. <a href="http://europepmc.org/abstract/med/17019292">Studies show little historical change</a> in leisure time physical activity. But there have been big declines in occupational physical activity as workplaces have become automated and the service economy replaces manufacturing and farming. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/79413/original/image-20150427-23945-ukvmrg.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/79413/original/image-20150427-23945-ukvmrg.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/79413/original/image-20150427-23945-ukvmrg.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/79413/original/image-20150427-23945-ukvmrg.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/79413/original/image-20150427-23945-ukvmrg.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/79413/original/image-20150427-23945-ukvmrg.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/79413/original/image-20150427-23945-ukvmrg.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">Surprisingly, there’s not much evidence that people are eating more.</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/donhomer/7130049599">Michael Bentley/Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<p>A <a href="http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0019657">study looking at work-related physical activity</a> over five decades showed declines of about 500 kilojoules a day in energy expended on the job by US workers. Another spanning 45 years suggests the time women spent on <a href="http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0056620">domestic chores</a> required about 1,000 kilojoules less each day in 2010 than they did in 1965. </p>
<p>Declines in energy expenditure of this magnitude are more than enough to account for historical increases in fatness.</p>
<h2>And the meat</h2>
<p>At the same time, and more surprisingly, while there are more calories around, there’s not much evidence that <a href="http://www.ncbi.nlm.nih.gov/pubmed/23426032">adults</a> or <a href="http://www.cdc.gov/nchs/data/databriefs/db113.pdf">children</a> are eating more, at least since the turn of the century. </p>
<p>In 2008, one of my graduate students, Jo Stevenson, systematically reviewed studies reporting the energy intake of children. She found 2,148 reports dating back to 1856, covering 425,905 mainly European, North American and Australian children. </p>
<p>There was a consistent decline in energy intake of school-aged kids from 1920 onwards, at the rate of about 2% to 3% per decade, flattening out in the late 1990s. By 2000, kids were eating about 20% less than they did in 1920. Even conservatively allowing for under-reporting by fatter kids and methodological differences, the decline was still of the order of 1% to 2% per decade. Unfortunately, this research wasn’t published so I can’t link it here.</p>
<p>The evidence that adults are eating more may also be very suspect. Data from the periodic <a href="http://www.cdc.gov/nchs/nhanes.htm">National Health and Nutrition Examination Surveys</a> (NHANES) in the United States are often used to indicate upward trends in energy intake. But <a href="http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0076632">Blair’s team</a> has previously convincingly argued – in a peer-reviewed article published in a well-respected journal – that these trends are likely to be artefacts resulting from changes in research methodology, and that dietary data are inherently unreliable anyway.</p>
<p>So historically, the evidence is that <a href="https://www.youtube.com/watch?v=hvrupRQD44I">it ain’t the meat it’s the motion</a>. But in practical terms, if you’re overweight, diet plus exercise is your best bet. And there’s something in that to satisfy both camps. </p>
<p>Even so, I suspect that many disinterested purveyors of truth are likely to end up as collateral damage in the crossfire of the obesity wars. And I, for one, am ducking for cover.</p><img src="https://counter.theconversation.com/content/40822/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Tim Olds receives or has received funding from the National Health and Medical Research Council, the Australian Research Council, Beyond Blue, the Natiional Stroke Foundation, the Physiotheraopy Research Foundation, the Commonwealth Department of Health and Ageing, the Australian Food and Grocery Council, SA Health, the Australian Defence Force and the Defence Science and Technology Organisation. He has received conference sponsorship from Coca-Cola, and receives royalities from UNSW Press.</span></em></p>Obesity researchers have been in a tug of war about obesity for decades now. So what does the evidence show about the latest offensive in the obesity wars?Tim Olds, Professor of Health Sciences, University of South AustraliaLicensed as Creative Commons – attribution, no derivatives.