tag:blogger.com,1999:blog-1812431336777691886.post6821375640074875997..comments2024-02-29T03:57:00.088-05:00Comments on The Mermaid's Tale: The WHO and recommendations on sugar consumption: an ill-posed problemAnne Buchananhttp://www.blogger.com/profile/09212151396672651221noreply@blogger.comBlogger12125tag:blogger.com,1999:blog-1812431336777691886.post-77725030598766552202014-03-10T21:30:13.911-04:002014-03-10T21:30:13.911-04:00True, they haven't specified the public health...True, they haven't specified the public health interventions they have in mind -- recommending a tax on high-fructose corn syrup, as you suggest, or the removal of soda from schools or the like -- and you're right that that is different from recommending that individuals cut down their sugar intake. <br /><br />But both types of recommendations would be based on the same evidence, and the same epidemiological methods that are really good at identifying strong point-cause risk factors, and not so good when the effect is weak, long-term, confounded, contextually dependent, and so on. Anne Buchananhttps://www.blogger.com/profile/09212151396672651221noreply@blogger.comtag:blogger.com,1999:blog-1812431336777691886.post-81336969834761262752014-03-10T21:08:58.530-04:002014-03-10T21:08:58.530-04:00I think we can blame the media for a lot of the co...I think we can blame the media for a lot of the confusion. <br /><br />Here's part of the text from the WHO webpages: "When finalized, the recommendations in this guideline can be used by programme managers and policy planners to assess current intake of free sugars relative to a benchmark and develop measures to decrease intake of free sugars, where necessary, through public health interventions."<br /><br />And here's the lead on the CNN story: "The World Health Organization wants you to stop eating so much sugar. Seriously."Geoff Doughertyhttp://www.geoffdougherty.comnoreply@blogger.comtag:blogger.com,1999:blog-1812431336777691886.post-49643562164178497852014-03-10T19:13:32.423-04:002014-03-10T19:13:32.423-04:00You bring up a very important point about the WHO&...You bring up a very important point about the WHO's goal being to shift population level obesity and non-communicable disease rates. And, by the way, they are still taking comments on their recommendation, as far as I know, so it is not yet writ in stone. <br /><br />But as I read it, they aren't recommending population level action -- they are recommending that individuals reduce their sugar consumption. Our sugar consumption. Based on studies that are less than convincing. Indicting a single nutrient is always suspect, to my mind, because of confounding and because of heterogeneity. <br /><br />You are doing a much better job making their case than they have done! It is good that NCDs are getting the attention of the WHO. But we don't know what makes us fat. Today it's antibiotics! I think if sugar was the major contributor, epidemiological methods would be able to determine it because they are best at finding risk factors with large effects. <br /><br />The other side of Rose's point is the ecological fallacy, of course. Pity epidemiology. Anne Buchananhttps://www.blogger.com/profile/09212151396672651221noreply@blogger.comtag:blogger.com,1999:blog-1812431336777691886.post-77919859589595327632014-03-10T18:07:18.490-04:002014-03-10T18:07:18.490-04:00The WHO's actions would look more sensible if ...The WHO's actions would look more sensible if they did a better job of communicating the context in which they're developed. The WHO isn't making a clinical recommendation with the hope that the most obese individuals will eat less sugar. It's making a policy recommendation that member nations can use to develop population-level health interventions that will shift the entire distribution of BMI to the left, regardless of its variance. Ideally those interventions (like, say, a tax on high-fructose corn syrup) would work regardless of whether individuals can stick with a low-sugar diet for several months. <br /><br />There's a classic article on the difference between clinical and population health interventions here: http://ije.oxfordjournals.org/content/14/1/32.abstract<br /><br />Right now, many developing nations are undergoing an epidemiologic shift. In the past, their mortality was determined largely by infectious disease, and in the future it will be determined mostly by chronic disease. Without intervention, they will undoubtably develop the same kinds of norms and policies that led obesity, diabetes and cardiovascular disease to be huge problems in the U.S. <br /><br />So the impetus to act, even in the absence of perfect science, is strong. Although honestly I think the science on sugar is on par with the science on many other potential determinants of health. It would be great if it were better. Some authors should have used intention-to-treat study designs and didn't. The effect sizes are on the small side, and not all of the studies point in the same direction. <br /><br />But taken together, they do seem to suggest that sugar makes you fat. And although observational studies, especially poorly designed ones, may be confounded, they have a pretty good track record of getting the direction of effect right, even if they overstate the effect size. Geoff Doughertyhttp://www.geoffdougherty.comnoreply@blogger.comtag:blogger.com,1999:blog-1812431336777691886.post-60353827989445642692014-03-10T15:01:04.285-04:002014-03-10T15:01:04.285-04:00Perhaps, if the people in your circles won't t...Perhaps, if the people in your circles won't take this argument seriously because it comes from Anne Buchanan, they need to open their minds a bit bit?Jim Woodnoreply@blogger.comtag:blogger.com,1999:blog-1812431336777691886.post-57229317108420858252014-03-10T12:55:46.966-04:002014-03-10T12:55:46.966-04:00Thanks for these comments. Perhaps a more relevan...Thanks for these comments. Perhaps a more relevant point about the 2 lb weight loss is that the studies were only 10 weeks to 8 months in duration, so it's possible that given more time, people who reduce sugar consumption would lose more weight. But the problem is that we don't know that from the studies that the WHO based their recommendations on. And, we certainly don't know that people can maintain low sugar diets or weight loss long term. <br /><br />And then there's the confounded difference between statistically significant and biologically significant findings, as well. <br /><br />I am not arguing that sugar is harmless. I don't think we know that one way or the other; I certainly don't. I am arguing that the studies that the WHO based its recommendation on are, to my mind, not sufficient evidence. Anne Buchananhttps://www.blogger.com/profile/09212151396672651221noreply@blogger.comtag:blogger.com,1999:blog-1812431336777691886.post-41402763055429641002014-03-10T12:52:42.787-04:002014-03-10T12:52:42.787-04:00These are good points, but the 2-pound issue depen...These are good points, but the 2-pound issue depends on the variance not just the mean. It is possible that it's just a typical common response level (very small). It is also possible that some people are way more sensitive and raise the average; if this were the case, then they are the ones who should be identified for health-care reasons.<br /><br />The correlation of causes in your last sentence is a huge problem for any sort of public health research; it would mean that it is not, in fact, the sugar but something one might call the 'eating habit'. That to me seems far more likely than that sugar, per se, is the villain in this particular story.Ken Weisshttps://www.blogger.com/profile/02049713123559138421noreply@blogger.comtag:blogger.com,1999:blog-1812431336777691886.post-25029384590725398112014-03-10T12:28:50.027-04:002014-03-10T12:28:50.027-04:00One thing to consider is that, while a two-pound w...One thing to consider is that, while a two-pound weight loss may not seem like much on an individual level, small changes multiplied across a large number of people actually yield big gains in population health, especially when the health issue is as prevalent as obesity. <br /><br />Another: While it would be great if we could design experiments that looked at replacing sugar with some other food, and then measure weight loss, there is some evidence that the relationship between sugar and weight is complicated by the fact that eating sugar encourages one to eat more of everything else, too. Isoenergetic studies don't really capture this dynamic, which means that they may underestimate the effect of sugar. Geoff Doughertyhttp://www.geoffdougherty.comnoreply@blogger.comtag:blogger.com,1999:blog-1812431336777691886.post-32600336047265585352014-03-09T12:53:56.074-04:002014-03-09T12:53:56.074-04:00Wow, have you been reading my stuff?
(My posts on...Wow, have you been reading my stuff?<br /><br />(<a href="http://jaymans.wordpress.com/category/health-and-medicine/" rel="nofollow">My posts on Health and Medicine</a>)<br /><br />This was brilliantly written! Please don't take this the wrong way, but I wish it didn't come from you. This is because the people in my circles will be apt to not take this seriously. But I think you're quite correct. The evidence that sugar (or for that matter, most dietary components) is harmful or leads to weight gain is lacking. Indeed, I made much the same point, even down to questioning tooth decay. I think in the zeitgeist to blame health outcomes on lifestyle, people have sacrificed sound scientific practice. Indeed, whole disciplines in this space are effectively compromised, because slipshod research methods are held up to be good practice, which is sad.<br /><br />Thanks a lot for this post.JayManhttp://jaymans.wordpress.com/noreply@blogger.comtag:blogger.com,1999:blog-1812431336777691886.post-72482132441469397312014-03-09T12:13:11.567-04:002014-03-09T12:13:11.567-04:00We are 'fed' similar kinds of stories by t...We are 'fed' similar kinds of stories by the media and (sadly) the journals every day. The flurry of definitively stated but easy to critique and conflicting claims means we have no scientific way to determine what to do. But we know that moderation works, at least as well as anything else in most of these situations.Ken Weisshttps://www.blogger.com/profile/02049713123559138421noreply@blogger.comtag:blogger.com,1999:blog-1812431336777691886.post-23563393517180747702014-03-09T11:51:53.336-04:002014-03-09T11:51:53.336-04:00There are risks to this kind of nonsense. I watche...There are risks to this kind of nonsense. I watched as a well educated, extremely health conscious mother transitioned her 9 month-old son from a diet of 100% breast milk (which has a lot of sugar) to an essentially sugar-free diet rich in fiber, vegetables and little meat. He dropped from the 60th percentile in weight to the 4th, and began to accrue language and social developmental delays. He was rescued by a scandalous intervention - ad libitum access 2 days each week to unlimited popsicles, ice cream and fruit juices. He's now back at the 55th percentile, and his delays have reversed.Kirk Maxeyhttps://www.blogger.com/profile/11864529687578909475noreply@blogger.comtag:blogger.com,1999:blog-1812431336777691886.post-43130677568883742272014-03-09T10:30:14.607-04:002014-03-09T10:30:14.607-04:00This attack on sugar reminds me of the other kind ...This attack on sugar reminds me of the other kind of attacking that our world leaders like to do with little evidence. Holly Dunsworthhttps://www.blogger.com/profile/05260104967932801186noreply@blogger.com