Tuesday, June 19, 2012

Does Dieting Increase Diabetes Risk?



That's certainly the message that HAES practitioner Linda Bacon wanted her followers to believe. In fact her tweet suggests that "even short periods of calorie restriction" increase diabetes risk.

In case you're not familiar with Dr. Bacon her work challenges the assumptions made about obesity and she has been highly critical of studies linking obesity with morbidity and mortality.

In an interview she gave to Med Journal Watch she explains why she believes not everyone agrees with her conclusions,

"My experience from having worked closely with many obesity researchers who are more conventionally-minded than me is that they are so strongly mired in their assumptions, that they don't look at the evidence."
And now back to diabetes and dieting, the story of which in this case begins back in time during the Dutch famine of World War II which they not so affectionately call the Hongerwinter (hunger winter).

It was September 1944. The Germans blockaded Holland and cut off food and fuel shipments to punish the Dutch people who opposed the Nazi regime. Food stocks dwindled. By the end of November rations amounted to fewer than 1,000 calories a day, and by February, to 580. 4.5 million people suffered, and over 22,000 perished. At the famine's worst daily rations amounted to half of a medium sized potato and 2 slices of bread. To compound matters, fuel was nearly impossible to come by and despite frigid winter temperatures, gas, heat and electricity were turned off. The famine lasted until May 1945.

Can you imagine being a child in Holland during the famine? The suffering and the horror they must have felt are unfathomable and when coupled with the severe and prolonged under-nutrition they experienced perhaps it's no surprise that their cohort have seen increases in risk of a variety of medical conditions including type 2 diabetes.  It's their experiences that Dr. Bacon uses as the source for her diabetes related caution against dieting.

The link Dr. Bacon provided in her assertive tweet about dieting and type 2 diabetes risk led to a a paper entitled, "Famine Exposure in the Young and the Risk of Type 2 Diabetes in Adulthood". In it researchers studied 7,557 Dutch women who endured the Hongerwinter and who on average were 9 years old when it occurred. Subjects were stratified into 3 groups on the basis of their self-reported exposure to famine - none, moderate and severe. The researchers found a small and statistically significant increase in risk to those women who reported themselves as moderately or severely affected by famine and this risk, while slightly attenuated, persisted after controlling for age at start of famine, education, BMI, waist circumference and waist to hip ratio.

The authors also noted that their study was unable to distinguish whether or not this association was related to under-nutrition or to famine related stress and point readers to a Finnish study that found a similar increase in lifetime risk of type 2 diabetes associating with the results of a psychological stress test in childhood war evacuees.

So in the end it would seem that from reading the evidence enduring a moderate to severe famine at a young age increases the risk of developing type 2 diabetes perhaps by way of the impact of under-nutrition, or perhaps by way of the impact of psychological stress, or perhaps by another as yet not elucidated cause.

In no way shape or form does this data suggest that "dieting" increases the risk of type 2 diabetes and in no way shape or form is suffering through a famine where daily rations include 2 small slices of bread and half a potato fairly described as a "short period of calorie restriction".

For Dr. Bacon this seems to be a bit of a pattern - slam conventional researchers for being, "so strongly mired in their assumptions that they don't look at the evidence", and then be so strongly mired in her assumptions that either she herself doesn't look at the evidence, or if she does her confirmation bias is so powerful that she'll happily find a way to present it to fit her narrative (click here for more examples). When I questioned her about this particular example on Twitter, despite her battle cry on Huffington Post of, "Show me the data we demand, and you should, too", she blocked me.

A few days ago dietitian and HAES advocate Julie Rochefort asked me on Twitter what barriers I saw to mobilizing HAES into practice. The main one I see seems to be regularly reflected by Dr. Bacon - knee jerk anger and either the willful manipulation of evidence, or a lack of critical appraisal of data so long as it seems to fit the HAES storyline.

Dr. Bacon is certainly HAES' most visible champion and role model. Responding to criticism with anger and manipulating or simply not critically evaluating HAES friendly data undermines the credibility of HAES as a whole, makes HAES easier for detractors to dismiss, and sets an absolutely terrible example for HAES practitioners and supporters to follow.

Annet van Abeelen, Sjoerd Elias, Patrick Bossuyt, Diederick Grobbee, Yvonne van der Schouw, Tessa Roseboom, & Cuno Uiterwaal (2012). Famine Exposure in the Young and the Risk of Type 2 Diabetes in Adulthood Diabetes DOI: 10.2337/db11-1559

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22 comments:

  1. Anonymous9:01 am

    I'm another dietitian who supports the concept of HAES but I'm finding more and more that in this world of obesity research there are 2 strongly opposing camps of people and both are strongly biased. There are few people out there in the middle saying reasonable things and actually evaluating the evidence well. Yoni, your opinions and critical appraisals are one of my more trusted sources of info and I thank you for that.

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  2. I absolutely believe in health at every size, I also believe in eating whole natural foods, processed as little as possible in the correct portions, and getting adequate exercise. I know that dieting contributed greatly in my becoming morbidly obese by slowing my metabolism but I also admit that it was not the ONLY factor.
    Obesity is not a one size fits all issue. There are to many contributing factors to place blame on any one cause. And the same holds true with diabetes.
    My issue with HAES proponets is they tend to forget the word "every" in the title... Every means every... but what may be a healthy weight for one may not be for another. At 400 plus pounds I was dieing. I opted to have bariatric surgery after much research and great thought. I lost 200 pounds in a little over a year. I am still considered obese. But I am healthier then I have been in 30 years, I am more active and happier. I I did not have the surgery to become thin, I did it to save my life, and to actually have a life that was worth living. Many HAES proponets would condemn me for the choice I made. And that is where my problem lies. It is Health at every size. Isn't the emphasis suppose to be on health?
    javascript:BLOG_CMT_subscription.toggle()

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  3. Anonymous9:51 am

    I am a dietitian who recently had the pleasure of spending the day with HAES experts and I must say I don't see that Yoni's perspective is all that different! Let's not fight and instead remember what HAES is all about:
    (a)accepting and respecting the natural diversity of body sizes and shapes;
    (b)eating in a flexible manner that values pleasure and honors internal cues of hunger, satiety and appetite; and
    (c)finding the joy in moving one’s body and becoming more physically vital.
    (From: http://www.lindabacon.org/haes.html)

    And I think if someone gets angry it is because they are passionate. We don't all have to be cold and emotionless, do we??

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  4. Great post Yoni!

    It seems that Linda also failed to consider additional attributes of famine sufferers that might set them apart from non-sufferers. It's my understanding that people who have gone through ordeals such as the Dutch famine often develop psychological issues related to food such as overeating and food hoarding that might also play a role in the development of diseases such as Type 2 Diabetes.

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  5. Rhodia10:59 am

    Diana, people who have dieted also develop psychological issues related to food. I certainly did. In fact, I developed binge eating disorder.

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  6. Yoni,
    I'm a proponent of HAES and I agree with your assessment, somewhat. I think the Dutch famine demonstrates what kind of damage can be done by extreme, sustained caloric restriction. It's a snapshot of severe circumstances and it's difficult to tease out the relationships between caloric restriction, chronic stress and metabolic disorders. And we already know that chronic stress contributes to metabolic disorders, which is why we fight against weight-based stigma and shame.

    In any case, I think the link between weight cycling and insulin resistance can still be made, even without citing the Dutch famine. Walter Willett's work on weight cycling and diabetes draws a distinct connection between weight cycling and long-term weight gain, but attempts to distance the relationship between WC and t2d. Willett's other work on weight cycling confirms the WC/BMI link as well.

    But if BMI is so important in the establishment of diabetes, then it seems that the effect of weight cycling on BMI should be seen as part of the increased risk of diabetes too, shouldn't it?

    But what may really be driving both weight gain and diabetes is the way that weight cycling generally affects our metabolic health. The best explanation I've read on why weight cycling causes harm comes from JP Montani's "Repeated Overshoot Theory," which states that while during the weight loss phase a person's metabolic indicators improve, the instant a person enters the refeeding phase, blood pressure, blood sugar and blood lipids skyrocket. So for each cycle there's a "healthy" phase and an "unhealthy" phase, and with each cycle, the "unhealthy" phase causes wear and tear on our metabolic systems.

    And since most diets are doomed to fail, this "repeated overshoot" of our metabolic health is an inevitable part of the weight loss process and, over time, severe weight cyclers develop the very symptoms that we blame on BMI alone.

    Of course, we need to study this relationship further, but given the evidence of the effects of weight cycling, it would be valuable to learn more.

    So, when I personally refer to the damage of caloric restriction as a means of losing weight, I begin with weight cycling, since long-term caloric restriction is nearly impossible for most people.

    And I agree completely with you that we need to follow the evidence and not be led by our desire to prove dieting wrong at every available moment. There's plenty of evidence to support HAES as it is.

    Peace,
    Shannon

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    Replies
    1. Hi Shannon,

      Thanks for the thoughtful response.

      You know I too believe that dieting, especially in the classic weight cycling yo-yo use of the term may increase risk of diabetes by overshoot.

      Whether the risk is due to a metabolic overshoot, or a straight weight relatable increase in insulin resistance, I'm not sure anyone truly knows, but either way it's not good news and is one of the reasons that I too am staunchly opposed to traumatic and restrictive dieting.

      Keep fighting the good fight!
      Yoni

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    2. Thank you, Dr. Freedhoff. I greatly appreciate your response.

      Peace,
      Shannon

      Delete
  7. Anonymous12:55 pm

    Picking fights with other people who do not share your view is getting tedious. FWIW, I share your point of view on most issues, but being shocked and appalled at what others believe is not the way to invite intelligent discourse. An argument based on ideas rather than personal attacks is much more compelling.

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  8. I also meant to comment on Linda's comment regarding conventional physicians. Dr. Freedhoff, there is a distinct difference in the obesity information coming out of Canada and that of the United States. Canada seems to be successfully de-emphasizing stigma and shame, and focusing on healthy behaviors regardless of body weight (with some exceptions).

    But the United States has only ramped up the rhetoric, in spite of the evidence to the contrary (see Weight of the Nation... Dr. Samuel Klein's work on the small amount of weight loss necessary for health, yet the focus is still largely on making obese people normal-weight people). It's very difficult to find a physician who doesn't look sideways at you when you say "I'm making healthy behavior changes regardless of where my weight ultimately settles." In the States, weight loss is still the primary prescription, and exercise and healthy foods are merely tools to that end. And when you question many of the conventional physicians, they do bristle at the idea that fat can be fit and they often dismiss or play down the evidence supporting that view.

    So, I think what Dr. Bacon says is accurate, but I don't think you need to apply it to yourself. It's a particular mentality that she is speaking to, and it's all too prevalent in our healthcare system. I completely share her frustration with this.

    Just my two cents on this issue.

    Peace,
    Shannon

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  9. So, I'm still stuck on your funny Friday video. Would you give a back massage to Linda Bacon? (By the way, Gary Taubes is a journalist, not a scientist. He pretends well, but is as unworthy of your back massage as Rhona Applebaum, whom I think is a scientist . . . with an employer issue.)

    You wonder why everyone can't get along. You crack me up. The chief arsonist wonders why there are so many fires happening these days. Not that I disagree with this fire. Linda Bacon is not the best spokesmodel for HAES. Your post is right in pointing out her contradictions.

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    1. I can see that.

      Perhaps your stickiness is the difference between disagreement/polite debate and reacting to disagreement as if someone is insulting your god.

      Regarding Dr. Bacon - would happily trade back rubs with her.

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  10. Anonymous2:36 pm

    My mother suffered famine during WWII as a pre-adolescent and now suffers from type 2 diabetes. It seems to me possible that her experiences of war and deprivation set up a lifelong disordered relationship with food (which I have had to deal with as well as a kind of echo effect) that might have been just as much a contributing factor as that early period of caloric deprivation.

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  11. Anonymous2:51 pm

    I think you hit the nail on the head when you say that what happens when you starve an on average normal weight population (back then presumably including a lot less overweight people) may not be very relevant for overweight people on a sensible, (merely) calorie restricted diet. It may have validity though for normal or underweight people who diet for whatever reason (modeling, sport, obsession, eating disorder)

    As a historical aside: On 29 April 1945 a temporary truce was negotiated and the British bombers, many flown by Canadian crews, started dropping food in designated air corridors. My country still owes a debt of gratitude for that to yours.

    The operation was aptly called ´Manna´. The American air force joined in a couple of days later. As if to highlight cultural differences they called their operation ´Chowhound´.

    Here's some footage of food being dropped at tabletop height.
    http://www.youtube.com/watch?v=c6r66DCvp9I
    http://www.haagsefilmbank.nl/archives/1483

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  12. Annabelle4:38 pm

    The HAES people regularly hand bullets to the firing squad. They have a really good scientific idea, that they then do everything they can to undermine.

    Linda Bacon and her colleagues would be taken much more seriously if they weren't so (a) defensive and (b) ready to tweet and Facebook every pseudo-scientific idea that apparently supports their position.

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  13. Okay, this may be a small quibble but nowhere in your post do you define what HAES stands for. I finally gleaned from one of the comments that it possibly stands for Healthy At Every Size. It's one of my pet peeves that people use acronyms without defining them in the beginning. I'm a relatively new reader of your blog or possibly I would know like all the other commenters seem to. Please keep in mind that people may not be as conversant with the jargon as you are.

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    1. It's actually Health, not Healthy at every size. I've seen "Healthy" At Every Size used to denigrate it -- implying its proponents believe that 60 or 600 pounds is equally as healthy as 160.

      I'm a fan of Linda Bacon, but I can see where she might have overstretched here. I don't go as far as many to say that dieting is always contraindicated. What I do believe, though, is that it's overprescribed without any real discussion of its drawbacks or whether it's even appropriate for people who are perfectly metabolically healthy at larger sizes. One ill-advised tweet does not mean that all of HAES is invalid.

      Delete
  14. Roman8:07 am

    I went thru 18 mos of famine in 1944-45 at ages 5 - 6 during WW2 and have diabetes type 2 now. Don't know if there is a link. There is no history of diabetes in my family and I have no eating disorders. Very unexciting history.

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  15. My mother is a dutch Jewish Molecular biologist who at age 90 still has all her faculties and understands hunger. She has a disordered relationship with food but [hoarding etc]as a survivor of world war 2 and the Marshall Plan initiatives wonders why in the obesity debate the impact of DDT and the mass sprayings by the US military throughout Europe and the Pacific in particular Samoa [Samoa appears to have some of the highest obesity figures in the world]are not factored into the obesity debate.DDT is mutagenic and may have tampered with 3rd generation ghrelin.She has researched this all her life among Pacific people.Please give it some thought.

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  16. I think there's a lot of oversimplification going on here, and some pretty adversarial stances. I'm sad to see them but not surprised.

    I don't see Linda Bacon's tweet as "angry" at all, and have no idea where you get that from. And I think you know as well as I do that tweeting a link to an interesting study is a common practice that offers food for thought to followers. Frankly, none of us including the researchers in this case fully understand the connection between early malnutrition and later diabetes. No one is saying they know. But it's an interesting correlation and one worth pointing out on Twitter.

    For someone who says he's a proponent of HAES, you take every opportunity to hate on one of its voices. I wonder why you'd do that, and so publicly, rather than have a quiet dialogue with Dr. Bacon on substantive issues.

    --Harriet Brown

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  17. Anonymous5:01 pm

    I have a real problem with the way that you treated this tweet as through it were a fully formed scientific treatise, when it is limited to 140 characters. It is intellectually dishonest to criticize a short message for what it leaves out. With a bit more respect I believe we can work together and make a positive difference in this world.

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  18. Anonymous5:15 pm

    You know what's so ironic about the last two comments? That Dr. Freedhoff is suggesting HAES proponents tend to fail to critically appraise what they're reading and rely on their guts instead. Wonder if either of the last two commenters bothered to click on the link Dr. Freedhoff provided that clearly establishes this as a pattern for Dr. Bacon?

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