Big Diet and Exercise Study Fails to Find Benefit

Persons with Type 2 diabetes have an increased risk of heart disease and stroke. They are usually overweight. A study of about 5000 persons with Type 2 diabetes who were overweight or worse asked if eating less and exercise — causing weight loss — would reduce the risk. of heart disease and stroke. The difficult treatment caused  a small amount of weight loss (5%), which was enough to reduce risk factors. The study ended earlier than planned because eating less and exercise didn’t help: “11 years after the study began, researchers concluded it was futile to continue — the two groups had nearly identical rates of heart attacks, strokes and cardiovascular deaths.”

Heart disease and stroke are major causes of death and disability. Failure of such an expensive study ($20 million?) to produce a clearly helpful result is an indication that mainstream health researchers don’t understand what causes heart disease and stroke. Another indication is that the treatment being studied (eating less and exercise) was popular in the 1950s. Mainstream thinking about weight control is stuck in the 1950s. It is entirely possible that greater weight loss — which mainstream thinking is unable to achieve — would have reduced heart disease and stroke. If you understand what causes heart disease and stroke, your understanding may lead you to lines of reasoning less obvious than people with diabetes are overweight –> weight loss treatments).

One of the study organizers —  Rena Wing, a Brown University professor who studies weight control — told a journalist “you do a study because you don’t know the answer.” She failed to add, I’m sure, that wise people do not give a super-expensive car to someone who can’t drive. You should learn to drive with a cheap car. Allowing ignorant researchers to do a super-expensive study was a mistake. To learn something, do the cheapest easiest study that will help. (As I have said many times.) You should not simply do “a study”. This principle was the most helpful thing I learned during my first ten years as a scientist. In this particular case, I doubt that a $20 million study was the cheapest easiest way to learn how to reduce heart disease and stroke.

I made to work that makes no progress on major health problems is another sign of the lack of understanding reflected in the failure of this study. I have never seen this lack of understanding — which has great everyday consequences — pointed out by  any science blogger or science columnist or science journalist, many of whom describe themselves as “skeptical” and complain about “bad science.”



34 Replies to “Big Diet and Exercise Study Fails to Find Benefit”

  1. Given the population — old and very fat — I have a feeling no amount of weight loss would make a difference in mortality.

    There is plenty of evidence that modest weight loss+exercise can prevent/delay the onset on diabetes, but as a treatment once you get there it isn’t going to help.

  2. hi charlie! i agree w u and seth: its hard to reverse something like diabetes, hypertension….now, we cant eliminate cancers, it would put mds out of business!!! but… if one person can find a cure….and they dont have a special interest in keeping an oncology position.,,. a drug rep at purdue said: ya we want a cure for cancer. that means MONEY!!!! wow! i just thought of another research project. us personal scientists have to be healthy to live longer… i am going to put a bunch of snobby mds out of work!!! yeah!!!

  3. Charlie and L:

    Both of you say that diabetes can’t be reversed, but then how do you explain all the claims that weight loss surgery can cure type 2 diabetes?

    I would never consider having weight loss surgery, but I’m fascinated by all the claims that some weight loss surgeries reverse or cure diabetes. I’m not sure whether the “cure” could be due to bypassing an intestinal section that produces some hormones, or whether the surgery alters the gut microbiota and thus changes something. I think these issues need to researched further.

    I think one of the sad stories of medical history is the timing of the discovery and commercial production of insulin in the early 1920s, for two reasons:
    1. The discovery of insulin put a sudden end to some very promising research being done by Doctor Frederick Madison Allen, who had been treating diabetic patients with an extremely low-calorie “starvation cure.” Allen’s dietary approach was briefly hailed as a major breakthrough, but insulin gave people an alternative that let them avoid dieting. Dieting was, and still is, the better choice, and the focus should be on how to make diets more successful,
    maybe with some combination of low carb, high fiber, as well as prebiotics and probiotiics.
    2. Th discovery of insulin gave a tremendous boost to the BigPharma industry and the development of all the highly profitable bizarre drugs that have led researchers away from natural Darwinian medicine approaches that are based on sound evolutionary science.

    Seth: I say the same thing about the discovery of antibiotics. The cost of the discovery is rarely noticed. One big cost of that discovery was less attention to how to improve immune function. Another, as you say, was promotion of a drug=cure mentality, when other non-drug solutions are much better in the long run. Diabetes is an obvious example.

  4. “Allowing ignorant researchers to do a super-expensive study was a mistake.” Right on, Seth! Unfortunately, this is the name of the game in the publish or perish, grants as academic currency world.

  5. I have heard speculation that the reason why they cut the study short was not simply that it was obvious that the intervention group wasn’t successful. Instead they stopped early because they were seeing worse outcomes in the intervention group and they didn’t want to the last 2 years to highlight the trend.

    By stopping early, they can say “the outcomes between the intervention and control were the same” instead of finishing the trial and being forced to report that the intervention group (following the standard medical advice) did worse.

    Any thoughts on if there is any truth that rumor?

  6. The sad thing is: we know how to cure or dramatically improve outcomes in diabetes through changes in diet and exercise. We’ve known how for a few decades. It’s really easy.

    And to Seth’s point, the fellow who figured it out was a self-experimenter who had diabetes himself, figured out that the standard protocol (which hasn’t changed) didn’t work, and used a simple tool (now cheap and readily available) to solve the problem.

    But the diet is 100% the reverse of the American Diabetes Association plan, so it’s ignored.

    One is forced to come to the conclusion that the perceived status of the medical profession is more important than patients’ lives. They’d be forced to say: we blew it, we made millions of sick people sicker.

    This generation won’t do it. Neither did the one before.

    The fellow in the case above was an engineer. He discovered that doctors wouldn’t listen to someone who wasn’t a doctor. So he went to medical school and became a doctor. They still wouldn’t listen to him.

    His book, btw, is “The Diabetes Solution”.

    Seth: “They still wouldn’t listen to him.” That’s an overstatement. Richard Bernstein, the engineer you refer to, pioneered home glucose measurement, which is now a billion-dollar/year industry. The idea spread from Bernstein to med school professors to standard of care. Bernstein’s particular solution to high blood sugar, however — a very low carb diet — did not spread. I think with good reason: it is not a good idea. I found that walking one hour per day vastly improved my blood sugar. Eating a very low carb diet did not. When it came to the solution, I think Bernstein got it wrong.

  7. @jimPurdy; I think the reversal of diabetes with bariatric surgery is in the 5% range. It happens, but it is rare.

    Again, once you’re a full blown diabetic you’re going to be on drugs. Sorry.

  8. @charlie: or you could google it, and find out.

    “The clinical and laboratory manifestations of type 2 diabetes are resolved or improved in the greater majority of patients after bariatric surgery; these responses are more pronounced in procedures associated with a greater percentage of excess body weight loss and is maintained for 2 years or more. ”

    Bariatric surgery simulates a low-carb diet, essentially. That’s also often what is followed after the surgery. If you don’t you gain a lot if not all the weight back.

    Leads one to think it’s the diet, not the surgery, but clearly cutting part of your intestinal tract out is going to have some effect…

  9. Actually, Seth, it’s worse than that:

    Peter at hyperlipid suggests that the Look Ahead study was NOT halted early because of a supposed *lack* of difference in mortality between the study’s arms, but rather because It was well on its way of proving that the ADA diet killed MORE people (all cause mortality In the intervention arm was HIGHER than the other arm — and significance was rising — when they cut off the study.)

    In other words, it’s very likely that halting the study is a massive cover-up that will permit the standard of care from being corrected, resulting in the continued pointless deaths of thousands of people.

    They will do anything to keep from proving the unsurprising conclusion that feeding diabetics huge amounts of carbohydrate (the ADA diet) for years kills them.

    Seth: Peter at Hyperlipid says nothing to support his view that it is “very likely” that more people died in the intervention arm than in the control arm. Or if he does, I didn’t understand it.

  10. charlie’s “old and very fat” comment got me looking at the study’s participant metrics. I wouldn’t call them old – the average age was 59 (look ahead’s eligibility requirements were age 45-74).

    But yes they were very fat. The study specified a starting baseline BMI of at least 25, but the actual average BMI was 36! That bothers me more than the study’s cost. Their stated goal was to study “a diverse sample of overweight participants”; the sample they ended up with had way too many morbidly obese individuals.

    Seth: I think the study designers believed that these people were going to be more easily helped than people who were less fat. It’s a reasonable assumption. Which makes the failure to help them all the more damning.

  11. I covered the Look Ahead study for my publication, and there’s some misunderstanding here about the termination and what that means. The study did not fail. It was brought to an end by an independent data monitoring committee because upon analysis of the data, there was no chance of showing a difference in mortality between groups the test and control group. The study did not fail, it finished, and the data is valid and publishable and usable, and can be built upon for future studies. Although no benefit in terms of cardiovascular events was found for people with Type II diabetes, the study did confirm the benefits of the 5% weight loss in preventing Type II diabetes and for some other health outcomes. There’s been a huge gap between showing benefits for various surrogate health markers like blood pressure and actually proving that interventions can actually prevent heart attacks, which would be the ultimate holy grail of weight loss intervention. There is no data in the study showing that people in the weight loss group had higher mortality. The two groups were the same with no statistical difference. It’s a tough problem, and one of the problems, you are correct, is that much of the conventional wisdom is wrong–for example on the value of a low fat diet. I would disagree, Seth, that the $20 million was unjustified. There are countless small, retrospective studies on weight loss and diabetes interventions. What is needed is large, prospective studies to put many competing hypotheses to the ultimate test to see if they really have value. This was $20 million well spent because it tells us in no uncertain terms that weight loss alone is not a cure for Type II diabetes.

    Jim Purdy, you are confusing Type I and Type II diabetes. The starvation cure was only temporary. It delayed death in diabetic children, but did not prevent it. No one can survive without a functioning pancreas, and diet can not cure a condition that is caused by the failure of a major organ. Insulin was a life-saving revolution and continues to be a valuable, life-saving, life-prolonging drug for people with Type II diabetes. Diet can be used to reduce insulin consumption in Type I diabetes, but can never eliminate it. Diet interventions absolutely can reverse or cure Type II diabetes, however, and progress on that is not hindered by the availability of insulin because insulin is an intervention of last resort for that group, anyway.

    Seth: I think the $20 million would have been better spent on numerous small studies trying to understand what causes heart disease. Rather than on a test of a common-sense cure (weight loss). You mention “competing hypotheses” — that’s exactly it, there weren’t any competing hypotheses. There was just one idea, so simple-minded that to call it a “hypothesis” might be overstatement. There was no theory of heart disease that predicted that the intervention would not work — at least, the study organizers have not mentioned what that theory is.

  12. Institute of Medicine’s standard ‘recommended’ diet for non diabetics is 225 to 325 grams of carbs a day.

    I went to the ADA site, and couldn’t find a specific carb count, so I looked up a ‘meal plan’ ( and the particular one, featuring “Asian Flavors” had 192g of carbs. Barely less than that recommended by the standard American Diet.

    This is the current guidelines:

    This stood out:

    •For weight loss, either low-carbohydrate or low-fat calorie-restricted diets may be effective in the short term (up to 1 year). (A)

    I wonder why the low-carb version isn’t recommended more?

  13. “The primary objective of Look AHEAD is to examine, in overweight volunteers with type 2 diabetes the long-term effects of an intensive lifestyle intervention program designed to achieve and maintain weight loss by decreased caloric intake and increased physical activity. This program is compared to a control condition involving a program of diabetes support and education. The primary basis for the comparison is the incidence of serious cardiovascular events. Other outcomes, including cardiovascular disease risk factors, diabetes related metabolic factors and complications, and the cost-effectiveness of the intensive intervention are also studied.”

    It failed because it was testing a hypothesis, and it demonstrated that that hypothesis was not correct. Losing weight and exercising did not affect the end point.

    The fact that it failed doesn’t mean that nothing was learned…

    I agree with Peter @ Hyperlipid’s hypothesis: they cut it short because it was demonstrating that the intervention wing had a worse outcome, like the ACCORD trial.

  14. Catherine,

    The press releases said there was no difference in cardiovascular events, they did not, specifically, say “all cause mortality”.

    We’ll have to wait for the final report, and hopefully the raw data set, to see what really happened.

    BUT, the central hypothesis of the trial was that the diet and fitness intervention, in obese diabetics, would reduce CV events – but, after 11 years, it didn’t.

    Even “improvement” in other health markers – weight, treadmill fitness, blood pressure, HDL cholesterol, made absolutely no difference to CV events.
    so will they conclude that the diet does not work, and that many of the markers are not good indicators for CV health?

    If it means this paradigm is finally discarded, then the $20m was well spent, it the results are buried, and the ADA diet remains unchanged, then we have a real problem.

  15. Catherine,

    Here are two things that you might want to keep in mind when covering future studies:
    1) the word “data” is plural (e.g., “the data [are] valid and publishable”);
    2) The sentence “The two groups were the same with no statistical difference” is utterly wrong. It is statistically impossible to show that two groups are the same… “no statistical difference” really only means insufficient evidence to reject the null hypothesis, it provides absolutely NO support for the null hypothesis of no difference.

  16. CarbSane Asylum is doing some posts about this study:

    In the first link she discusses the possibility that poor compliance to the diet probably had a significant impact on the results:

    “Does anyone out there truly believe that if your average 250 lb person complied with a diet of 1500 cal/day for a decade would still weigh nearly as much? It sounds like this study included a diet phase early on (6 months perhaps?) during which the participants lost weight, and then maintained the losses. Did they continue the exercise? These are details I’d like to see when this study is eventually published up. How many are even following the “rigorous program” to any degree?”

  17. Carbsane goes on the warpath whenever there’s any threat to her beloved carbohydrates. She has so much hatred for Gary Taubes that you’d think he gave her a wedgie in junior high or something.

  18. Mark wrote, “the word ‘data’ is plural ”

    “It’s time to admit that data has joined agenda, erotica, insignia, opera, and other technically plural Latin and Greek words that have become thoroughly Anglicized as singular nouns, taking singular verbs. No plural form is necessary, and the old singular form, datum, can be left to the Romans.”

    From, Woe Is I: The Grammarphobe’s Guide to Better English in Plain English by Patricia T. O’Conner.

    Seth: I found 4 times as many Google results for “data is” than “data are”, supporting what you say. Here is a discussion:

  19. Seth, the hard thing is that insomnia happens frequently, but CV events are rare. I’m not sure how self-experimentation could address them unless you had a really good surrogate measure.

  20. “To learn something, do the cheapest easiest study that will help. ”

    In the technology space, this is akin to building what we call a Minimum Viable Product.

  21. “When it came to the solution, I think Bernstein got it wrong.”

    Bernstein’s a 70-something year-old Type 1 diabetic, who has no diabetic side effects (they all went away) and is in apparently perfect health. That’s not too bad for “wrong”.

    I work with a fellow who’s teenage son is also a type 1 diabetic. After going through the usual BS, they went to see Bernstein. Now, when they go see their local doctor, the nurses call everyone over because “You never see a Type 1 diabetic with perfect blood sugar control!”

    No, you don’t, unless you follow a VLC diet.

    My wife and I also reversed our pre-diabetes by going VLC: in my case, after failing with walking, running, mountain biking, going to the gym. At one point I was working out 12-16 hours a week. Never lost a pound, stayed prediabetic.

    I think Bernstein got the solution perfectly right.

    And you’re right that they listened to him about measuring glucose, but they missed the point of the measurement.

    Seth: Bernstein’s work was a huge advance, for which he deserves a Nobel Prize. Has Bernstein suffered any bad effects from extreme carb restriction? I am less sure than you that he is in perfect health. In your case, you tried walking one hour per day, and that failed?

  22. @mr tuck: thank u!! im glad one can reverse it! i never knew it was possible because i always thought a diabetic had to take insulin. wow!!

  23. Slightly OT – I’m surprised you haven’t spoken about and linked to – – as even the NYT has mentioned the results of this meta-analysis (albeit hidden in a small paragraph in Tuesday’s science section, whereas it should have been on page one). The Cochrane Collaboration is the group that has shown that hormone-replacement therapy was a bad idea, that mammography causes more harm than good, etc., etc.

  24. Bernstein says he’s in excellent health, with no ill effects from a long-term low-carb diet. In fact, all of his “progressive” diabetic complications regressed after going VLC.

    Jimmy Moore videoed Bernstein speaking a few years ago, where he discusses his symptoms and life:

    “Dr. Richard Bernstein (Part 1)–Nutrition & Metabolism Society Meeting–May 8, 2010”


    “Type 1 Diabetes No Match for Primal Lifestyle!”

    This fellow is effectively following Bernstein’s protocol, including the basal/bolus insulin scheme.

    Agreed about the Nobel. Unfortunately, until the medical profession can admit that there approach for treating diabetes is an utter failure, he’ll never get it.

  25. One observation about the “skeptics” community I share with your sentiment:

    They have very good instincts in going after the scientific “easy” target: all the alt-med, “integrative” and CAM quacks peddling their unscientific woo (though what the skeptics do is IMHO not very effective in combatting the obvious quack medicine).

    But when it comes to the scientific mainstream producing bad (or costly and useless) science (or rather non-science), they are completely lost. They decry the the profits that the alt-med cancer quacks pocket with their useless, dangerous and costly treatments (and the skeptics are right to decry this fraud by the alt-med quacks), but how many billions have been spend on the war on cancer in the last decades, and with what results?

    The hole state of affairs of the medical science is depressing, especially considering the gap between potential for research and progress we have in our modern societies, and the results the medical science has produced in the last decades.

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