On The Whole

New study provides another look at relationships between weight, disease & mortality

The scientists who brought you the good news two years ago that the 300,000- and/or 400,000-deaths-per-year -due-to-"obesity" statistic was erroneous and that being "overweight" was actually associated with decreased mortality have published a follow-up in today's issue of the Journal of the American Medical Association. Their conclusions may confuse (or perhaps irritate) those who bought into last week's food- and fat-nanny scare in which fatness and some foods were said to cause cancer and so-called "normal" weight was presented as a panacea.

Katherine M. Flegal, Ph.D. and colleagues Barry I. Graubard, Ph.D. , David F. Williamson, Ph.D. & Mitchell H. Gail, M.D., Ph.D. examined specific causes of death (such as cardiovascular disease and various types of cancers) and different weight categories. They reported finding significantly fewer deaths in the "overweight" (as compared to "underweight" and "obese") category.

As Gina Kolata writes in today's New York Times, Flegal et al. found that "overweight" people appear

less likely to die from a grab bag of diseases that includes Alzheimer's and Parkinson's, infections and lung disease....As a consequence, the group from the Centers for Disease Control and Prevention and the National Cancer Institute reports, there were more than 100,000 fewer deaths among the overweight in 2004, the most recent year for which data were available, than would have been expected if those people had been of normal weight....

Some who studied the relation between weight and health said the nation might want to reconsider what are ideal weights.

"If we use the criteria of mortality, then the term 'overweight' is a misnomer," said Daniel McGee, professor of statistics at Florida State University.

"I believe the data," said Dr. Elizabeth Barrett-Connor, a professor of family and preventive medicine at the University of California, San Diego. A body mass index of 25 to 30, the so-called overweight range, "may be optimal," she said.

The researchers found that "obese" people were NOT more likely to die of cancer than people in other weight categories, although they were slightly more likely than people of "normal weight"  to die of a few, specific cancers thought to be related to "obesity," including cancers of the colon, breast, esophagus, uterus, ovary, kidney and pancreas. "Obese" people were also LESS likely to die from OTHER cancers, such as lung cancer. "In the end," Kolata writes, "the increases and decreases in cancer risks balanced out." 

That's not surprising -- at least, not to those who are famliar with . In 1987 review of weight-related research, Paul Ernsberger, Ph.D. and Paul Haskew, Ph.D. found "obesity" to be associated with a lowered incidence of

• Premenopausal breast cancer
• Stomach cancer
• Lung cancer
• Colon cancer
• Meningioma
• Chronic Obstructive Pulmonary Disease (COPD)
• Chronic bronchitis
• Tuberculosis
• Urinary tract infection
• Osteoporosis
• Hip fracture
• Vertebral fracture
• Mitral Valve Prolapse
• Intermittent claudication
• Atherosclerotic rental artery stenosis
• Renovascular hyptertension due to fibromuscular hyperplasia
• Eclampsia
• Premature birth
• Vaginal laceration
• Hot flashes
• Premature menopause
• Anemia
• Diabetes Type 1
• Peptic ulcer
• Scoliosis
• Sucide

Ernsberger & Haskew also found "obesity" to be associated with a more favorable prognosis in

• Diabetes Type II
• Hyperlipidemia (excessive fats -- or lipids -- in the blood)
• Hypertension (high blood pressure)
• Rheumatoid arthritis

Ernsberger & Haskew pointed out that the fact that "obesity" is associated with many positive health conditions and outcomes indicates it is not a disease state.

When "obesity" is found to be associated with negative health conditions or outcomes, however,  we should keep in mind that many fat people (especially women) avoid health care because they have felt shamed and humiliated by encounters with medical professionals in which their health problems were ignored or appropriate tests or treatment refused until they lost weight. (See posts on this issue here and here.) In such cases it may be fat prejudice, rather than fatness itself, that results in poor health or mortality through stress, avoidance of health care, and poor quality health care.

Studies have documented health care professionals' negative opinion of fat people and reluctance to perform pelvic exams on very fat women. A 1998 Archives of Family Medicine study found that the higher a woman's weight, the less likely she was to have had a clinical breast exam, gynecologic exam, or Pap smear in the previous three years, even though she had had just as many -- or more -- doctor's visits as thinner women.

A 1994 Archives of Family Medicine article reported that 32% of female health care workers with a body mass index over 27 (considered "overweight") delayed or canceled physician appointments because they knew they would be weighed. What do you want to bet that the percentage of women considered "obese" who avoid health care appointments is even higher?

In The Forbidden Body, Shelley Bovey quotes an American woman in a therapy group:

Being fat is going to kill me, not because of the strain on my heart but because of the strain on my soul. I am going to have some warning signs and avoid seeking health care until it is too late, because I am sick and tired of the canned speeches from doctors and nurses blaming my weight for everything.

In Kolata's article Mitchell Gail, the physician-scientist co-author of the Flegal et.al study, gives "his personal opinon as a physician and researcher:

If you are in the pink and feeling well and getting a good amount of exercise and if your doctor is very happy with your lab values and other test results, then I am not sure there is any urgency to change your weight.

In a Washington Post article on the study, Steven N. Blair (professor of exercise science, epidemiology and biostatistics at the University of South Carolina), says "What this tells us is the hazards have been very much exaggerated. It's just not as big a problem as people have said."

"The take-home message is that the relationship between fat and mortality is more complicated than we tend to think," Flegal says in the Washington Post article. "It's not a cookie-cutter, one-size-fits-all situation, where excess weight just increases your mortality risk for any and all causes of death."

Although the study did not examine why being overweight might guard against dying from some diseases, Flegal said other research has suggested that extra heft might supply the body with vital reserves to draw upon to fight illness and aid recovery.

"You may not just have more fat. You may also have more lean mass -- more bone and muscle," Flegal said. "If you are in an adverse situation, that could be good for you."

Gina Kolata on Good Calories, Bad Calories

Gina Kolata. New York Times science reporter (and author of Rethinking Thin: The New Science of Weight Loss and the Myths and Realities of Dieting) has weighed in on "carbophobia" with a review of Gary Taubes's Good Calories, Bad Calories: Challenging the Conventional Wisdom on Diet, Weight Control, and Disease.

Taubes's book (which, as I posted earlier, John Tierney also recently wrote about in the Times) reports the poor science behind low-fat dietary religion and proposes instead that carbohydrates are evil -- err, contribute to "obesity" and disease.

Kolata acknowledges that

much of what Taubes relates will be eye-opening to those who have not closely followed the science, or lack of science, in this area....For example, he tells the amazing story of how the idea of a connection between dietary fat, cholesterol and heart disease got going and took on a life of its own, despite the minimal connection between dietary cholesterol and blood cholesterol for most people. He does not mince words. 'From the inception of the diet-heart hypothesis in the early 1950s, those who argued that dietary fat caused heart disease accumulated the evidential equivalent of a mythology to support their belief. These myths are still passed on faithfully to the present day.' The story is similar for salt and high blood pressure, and for dietary fiber and cancer.

In fact, Taubes convincingly shows that much of what is believed about nutrition and health is based on the flimsiest science. To cite one minor example, there's the notion that a tiny extra bit of food, 50 or 100 calories a day -- a few bites of a hamburger, say -- can gradually make you fat, and that eating a tiny bit less each day, or doing something as simple as walking a mile, can make the weight slowly disappear. This idea is based on a hypothesis put forth in a single scientific paper, published in 2003. And even then it was qualified, Taubes reports, by the statement that it was 'theoretical and involved several assumptions' and that is 'remains to be empircally tested.' Nonetheless, it has now become the basis for an official federal recommendation for obesity prevention.

Yet, Kolata points out, in his zeal to convince readers that carbohydrates make people fat by driving up insulin levels, which encourages the storage of fat,

...Taubes ignores what diabetes researchers say is a body of published papers documenting a complex system of metabolic controls that, in the end, assure that a calorie is a calorie is a calorie. He also ignores definitive studies done in the 1950s and '60s by Jules Hirsch of Rockefeller University and Rudolph Leibel of Columbia, which tested whether calories from different sources have different effects. The investigators hospitalized their subjects and gave them controlled diets in which the carbohydrate content varied from zero to 85 percent, and the fat content varied inversely from 85 percent to zero. Protein was held steady at 15 percent. They asked how many calories of what kind were needed to maintain the subjects' weight. As it turned out, the composition of the diet made no difference.

Kolata doesn't buy Taubes's premise.

If low-carbohydrate diets are so wonderful, why is anyone fat? Most people who struggle with their weight have tried these diets and nearly all have regained everything they lost, as they do with other diets.

Taubes claims that carbohydrates are "addictive," she reports. And, apparently, that permanent weight loss is possible if the addiction is "'overcome with sufficient time, effort and motivation.'" Kolata isn't convinced.

And neither am I.

Granted, I haven't read Taubes's book, but I've had plenty of exposure to the belief (I don't really want to dignify it by calling it a theory or hypothesis) that carbohydrates are addictive. I've seen many fat women who were "diagnosed" as "food addicts" in a misguided attempt to apply the 12-step program of Alcoholics Anonymous to weight, and told they need to "abstain" from "addictive" foods like wheat and sugar.

They've often lost weight, yes -- and then eventually started bingeing in response to the semi-starvation, with their weight soon returning to pre-diet setpoint levels or higher. These women had plenty of motivation, if only due to the fat-shaming environment they grew up and lived in. It didn't make any difference.

Taubes's book may do a service in alerting many to the poor science behind low-fat diet orthodoxy, and how scientific consensus can cascade into erroneous and even harmful beliefs and practices. But if he's proposing a low-carb diet as a health (and weight) panacea, he may be contributing to another false informational cascade.

Informational cascades, diet and fat

In today's New York Times review of Gary Taubes's new book Good Calories, Bad Calories: Challenging the Conventional Wisdom on Diet, Weight Control, and Disease,  John Tierney makes some good points about the folly of consensus in science and how that has manifested in dietary recommendations.

Tierney starts out by recounting former surgeon general C. Everett Koop's ludicrous 1988 claim that high-fat foods like ice cream are as dangerous to health as cigarettes.

The notional that fatty foods shorten your life began as a hypothesis based on dubious assumptions and data; when scientists tried to confirm it they failed repeatedly. The evidence against Haagen-Dazs was nothing like the evidence against Marlboros.

It may seem bizarre that a surgeon general could go so wrong. After all, wasn't it his job to express the scientific consensus? But that was the problem. Dr. Koop was expressing the consensus....He was caught in what social scientists call a cascade.

We like to think that people improve their judgment by putting their minds together, and sometimes they do. The studio audience at "Who Wants to Be a Millionaire" usually votes for the right answer. But suppose, instead of the audience members voting silently in unison, they voted out loud one after another. And suppose the first person gets it wrong.

If the second person isn't sure of the answer, he's liable to go along with the first person's guess. By then, even if the third person suspects another answer is right, she's more liable to go along just because she assumes the first two together know more than she does. Thus begins an "informational cascade" as one person after another assumes that the rest can't all be wrong.

Tierney points out that cascades

are especially common in medicine as doctors take their cues from others, leading them to overdiagnose some faddish ailments (called bandwagon diseases) and overprescrive certain treatments (like the tonsillectomies once popular for children). Unable to keep up with the volume of research, doctors look for guidance from an expert -- or at least someone who sounds confident.

[And I'll bet often those confidence-inspiring "experts" are pharmaceutical company/drug sales reps, or doctors who are funded by industries manufacturing and selling drugs and surgical supplies. See Kathleen Slattery-Moschkau's comedic film Side Effects, based on her experiences as a pharmaceutical sales rep.]

Tierney's article goes on to describe how the fat-is-bad theory and low-fat diet recommendations became popular despite many scientists' cautions.

The scientists, despite their impressive credentials, were accused of bias because some of them had done research financed by the food industry. And so the informational cascade morphed into what the economist Timur Kuran calls a reputational cascade, in which it becomes a career risk for dissidents to question the popular wisdom.

With skeptical scientists ostracized, the public debate and research agenda became dominated by the fat-is-bad school....But when the theories were tested in clinical trials, the evidence kept turning up negative. As Mr. Taubes notes, the most rigorous meta-analysis of the clinical trials of low-fat diets, published in 2001 by the Cochrane Collaboration, concluded that they had no significant effect on mortality.

Taubes claims that low-fat diet recommendations led Americans to switch to high-carbohydrate diets that led to "obesity" and disease. [That's true in my experience -- I recall when a popular Vanderbilt University-affiliated diet guru in Nashville began promoting high carb/low fat diets in the early 1980s, and I began making an effort to eat more complex carbohydrates thinking that was better for weight control. Yeah, I was still dieting back then.]

But, Tierney notes, Taubes acknowledges that the hypothesis that carbohydrates contribute to "obesity" and disease is unproven, and "the low-carb diet fad could turn out to be another mistaken cascade." (Emphasis mine.)

Read the full article here. Get more on the "low-fat, low-fact cascade" on Tierney's blog here.

Paul Campos on the "Harvardistas"

Paul Campos (author of The Obesity Myth) expands upon the subject of his recent Rocky Mountain News column in an article in The New Republic.

The gist? That faculty in the Harvard School of Public Health have been "pushing a phony claim" that being "overweight" has a major impact on health and mortality -- and the authority of the elite institution with which they are affiliated contributed to their pronouncements and research being uncritically accepted by physicians.

Of course, one reason the Harvard claims are treated with such respect is that they tell people what they want to hear. Their claims dovetail perfectly with social prejudices that declare one can never be too rich or too thin, and with the widespread desire to believe that sickness and death can be avoided if one follows the rules laid down by the appropriate authority figures.

Read the entire article here.

Jon Robison on the "Social Contagion of Obesity" study

Over at Techcentralstation Jon Robison (author of The Spirit & Science of Holistic Health) writes about the wacky New England Journal of Medicine article in which researchers claimed to show "the spread of obesity" through a social network.

You know the study I'm talking about -- it was widely reported in the media as "obesity is contagious" and "your friends can make you fat." See my post here for my take on the research -- and a comment from one of the study's co-authors.

Robison points out some of the basic problems with the study, especially the researchers' claims to have inferred direct causal relationships from observational/correlational data.

The upshot? Robison writes:

As absurd as the conclusions and proposed explanations for the findings of this research are, the lack of connection to reality of the proposed implications for public health certainly take the cake....The suggestions that follow can only be described kindly as out of touch with reality, not to mention a bit frightening -- less kindly as science in "la-la land." The authors suggest that we should try "treating people in groups," because people who are close to someone who loses weight are "more likely to get thinner." Seems to me there have been...um...decades of research, perhaps thousands of articles on this subject all coming to the same conclusion -- it doesn't work that way....one has to wonder upon what planet these researchers are looking down from their ivory towers.

I couldn't find a direct link to Robison's article, so to read it yourself you'll have to go to www.techcentralstation.com and search for "Junk Science is Contagious" after the article is moved from its current placement on the website's home page.

Canadian researchers report diabetes breakthrough....a possible cure?

Scientists at a Toronto hospital have reported discovering proof that the body's nervous system helps trigger diabetes, and that injecting diabetic mice with a substance to counteract malfunctioning pain neurons in the pancreas rendered them "healthy virtually overnight."

The findings were reported in the Dec. 14, 2006 issue of the journal Cell. Any treatment resulting from the line of research conducted by scientists at the Hospital for Sick Children is probably years away, however. Results from studies on human subjects are expected within a year or two.

"I've never seen anything like it," said Dr. Hans Michael Dosch, an immunologist at the hospital and a leader of the studies. "In my career, this is unique."

Their conclusions upset conventional wisdom that Type 1 diabetes, the most serious form of the illness that typically first appears in childhood, was solely caused by auto-immune responses -- the body's immune system turning on itself.

They also conclude that there are far more similarities than previously thought between Type 1 and Type 2 diabetes, and that nerves likely play a role in other chronic inflammatory conditions, such as asthma and Crohn's disease.

Dosch was interested in the presence of a large number of pain neurons "primarily used to signal the brain that tissue has been damaged" around the insulin-producing islets in the pancreas. He and his colleague injected capsaicin --

the active ingredient in hot chili peppers -- to kill the pancreatic sensory nerves in mice that had an equivalent of Type 1 diabetes.

"Then we had the biggest shock of our lives," Dr. Dosch said. Almost immediately, the islets began producing insulin normally. "It was a shock literally out of left field, because nothing in the literature was saying anything about this."

Read the rest of the Canadian National Post article here.

This finding further illustrates the interconnection between mind and body....which already was apparent in the fact that stress alone will raise blood sugar levels in people with diabetes.

The research seems to be directed toward pharmaceutical solutions to diabetes, but I think the findings also reinforce how behavioral/non-drug approaches might help.

We already know that exercise helps control diabetes -- people with Type 2 diabetes have been able to control their condition with diet and exercise alone, without medication, or have been able to get off medication, even without losing weight. (Which itself illustrates that weight -- or "obesity" -- itself is not the operative factor, or best element, to target in diabetes treatment.) What if something like massage therapy, which positively affects the nervous system by helping people relax as well as decrease pain, might also help people with diabetes? Might be worth exploring.

I do wonder, though, about the economic ramifications of a cure for diabetes. Not that these researchers are necessarily saying their findings will result in an outright cure....but still, the possibility got me thinking. Would pharmaceutical companies be interested in developing a drug that cures a chronic condition?

Think of all the OTHER drugs -- and medical equipment and supplies and clinics and research programs and organizations -- directly tied to diabetes that would soon have no target patient population if there was a cure. I've recently read (unfortunately, I can't remember where, so take this with a grain of salt) that when the discovery of antibiotics made tuberculosis curable, the industry built upon tuberculosis (sanitoriums, for instance) foundered and many businesses went bankrupt. A small price to pay to save lives, of course. But how motivated would pharmaceutical companies be to find  drugs that actually cure diabetes -- or any other chronic condition/disease?

Who knows? Still, it's good news, IMO. And until the results are in on how this works with human beings....perhaps it wouldn't hurt to get regular massages and apply hot sauce liberally at dinner.

Award-winning obesity researcher convicted of scientific fraud

A Sunday, Oct. 22  New York Times article provides a disturbing look at the world of scientific research.

A few months ago, former University of Vermont professor Eric Poehlman became the first researcher sentenced to prison for scientific misconduct. In 2005 Poehlman had pleaded guilty to lying on a federal grant application and "fabricating more than a decade's worth of scientific data on obesity, menopause and aging," according to the article in today's New York Times magazine.

Poehlman had been presented with the Lilly Scientific Achievement Award at the annual conference of the North American Association for the Study of Obesity six years ago. Poehlman's lecture at the NAASO event discussed his research on "energy dysregulation--an imbalance between the energy a person consumes and what he expends."

New York Times writer Jenneen Interlandi reports that Poehlman

presented fraudulent data in lectures and in published papers, and he used this data to obtain millions of dollars in federal grants from the National Institutes of Health....Before his fall from grace, Poehlman oversaw a lab where nealry a dozen students and postdoctoral researchers carried out his projects. His research earned him recognition among his peers and invitations to speak at conferences around the world. And he made nearly $140,000, one of the top salaries at the University of Vermont.

"Former protege" Walter DeNino turned Poehlman in. The investigation that ensued revealed years of fraudulent research and led to the "retraction or correction of 10 scientific papers, and Poehlman was banned forever from receiving public research money."

Poehlman was sentenced to one year and one day in federal prison, followed by two years' probation. When he pled guilty in 2005, he had "agreed to pay $180,000 to settle a civil complaint filed by the University of Vermont plus $16,000 in attorneys' fees" for the former staffer who had reported him, whom Poehlman had tried to discredit.

The plea came with an especially devastating admission: he acknowledged that his most noted research, the longitudinal study on menopause [published in the Annals of Internal Medicine in 1995], was almost entirely fabricated. Poehlman had tested only 2 women, not 35.

The article illustrates how so much of scientific research and peer review is based on trust that the data has been accurately collected, reported, and analyzed. With millions of dollars in grant money and six-figure incomes at stake, it's a wonder more obesity--and other--researchers haven't succumbed to faking data.

But then again, how do we know they haven't? Interlandi reports that other research associates, graduate students and postdocs had suspected Poehlman of scientific malfeasance. One had confronted Poehlman, but had been threatened with job loss. Faculty members to whom DeNino turned for guidance in the early stages of his suspicions told him his--DeNino's--career would be ruined if he blew the whistle.

"...the Poehlman case shows how a committed cheater can elude detection for years by playing on the trust--and the self-interest--of his or her junior colleagues," Interlandi writes.

Selling "obesity" hysteria

Paul Ernsberger, Ph.D. of Case Western Reserve Medical School gave me permission to share the following perspective on the etiology of "obesity" hysteria, which he posted on a private egroup for fat studies scholars:

I trace the onset of the the current medical war on obesity to the marketing blitz for fenfluramine, dexfenfluramine and phen-fen. These drugs created a network of 4 drug companies to promote pills that caused only a small amount of weight loss. The only way to get physicians to prescribe dangerous drugs that cause minor weight loss was to exaggerate the health risks of high weight. They created a speakers' bureau and they sent famous obesity warriors all over the country to "educate" physicians about the "dangers of obesity." These included all the usual suspects, whose careers were tremendously advanced by these lecture tours. The traveling lecturers (really propagandists) also came to dominate the talking heads on TV whenever a fat-related news story appeared.

The companies also sponsored "symposia" where speaker after speaker (most of them diet clinic directors) hammered on the epidemiology supporting a link between obesity and ill health. I attended many of these. As far as I recall, they never asked an epidemiologist to speak about epidemiology. These symposia took place at major medical conferences, and to draw a large crowd to fill the ballroom they included (very fattening) full dinner and often an open bar as well. No expense was spared. The odds are good that your personal physician or perhaps a senior physician that he or she trusts has been to one of these one-sided "symposia."

Because of FDA rules, companies are not allowed to promote drugs that are not yet approved. So how do they advance promotion legally? By promoting the indication. The makers of subutramine and orlistat started sponsoring symposia promoting a hysterical view of obesity years before they won FDA approval.

There you have it: a first-person account of the tactics used to sell the concept of obesity as a horrible, life-threatening disease, which in turn would obstensibly justify the prescription of medications with dangeous side effects. (Read Alicia Mundy's Dispensing With the Truth for a closehand look at this in regards to the diet-pill combo of phen-fen).

I doubt this process is limited to the selling of "obesity," by the way. Ernsberger's remark about epidemiologists not being asked (or paid) to speak about epidemiology at these industry-produced "symposia" reminds me of a meeting of a local health professionals' association I attended in Nashville, TN several years ago.

The meeting was held at an expensive restaurant and sponsored by a drug company, which provided free appetizers and meals to the physicians and psychologists in attendance. I arrived too late for the lobster appetizers, but my steak dinner was delicious.

The drug company also provided a physician who gave a 30-minute Powerpoint presentation on depression and the treatment of depression. Not once in the presentation did this physician mention psychotherapy, counseling, or any other non-pharmaceutical "treatment" of depression.

The physician who presented this unbalanced perspective was a gynecologist. Gynecologists, like other non-psychiatrist physicians, get about six weeks' worth of training in "mental health" issues in medical school. I wonder if a psychiatrist would have felt obligated to include non-pharmaceutical perspectives on depression. Possibly not, since psychiatric education has become almost entirely biologically oriented over the past couple of decades.

Ernsberger's quote above was posted in response to a post I made about the book Selling Sickness: How the World's Biggest Pharmaceutical Companies Are Turning Us All Into Patients (Ray Moynihan & Alan Cassels). That book contains a section on a New York ad agency staffer whose job was to work with drug companies to create new diseases (or rather the concept of new diseases) that could be marketed to the public in order to sell them the "solutions." I almost wrote "cures," but the goal really was/is to develop lifelong consumers of the product, not "cure" anything.

Selling Sickness opens with an anecdote about the former CEO of Merck saying (one might think almost wisfully) in an interview 30 years ago that what he really wanted was to be able to sell drugs to healthy people--vastly increasing his potential market. As Cassels and Moynihan noted, his dream has come true.

Science, Schmience

I don't know what the etiquette is about cross-blogging, but here's the text of a post I just made on the Health At Every Size radio show blog, Didn't want anyone to miss it.

Another volley has been fired in the "war against obesity," in the form of articles in yesterday's edition of the The New England Journal of Medicine that claim "excess" weight during midlife is associated with "an increased risk of death."

The claims are already getting play in the media...which is, for the most part, missing the real story. Which is that the data published in these articles actually says almost the opposite of what the authors claim. A close inspection of their own data shows that either "excess weight" was actually associated with LOWER mortality, or that there was no increased mortality risk.

How could the authors come to the opposite conclusion? By jettisoning data that didn't fit with their preconceived notion....err, hypothesis...that fatness is a bad, bad thing which needs much money thrown at it for research and public health purposes.

But don't take my word for it. Here's what Linda Bacon, Ph.D., associate nutritionist with the University of California, Davis, has to say about these studies (her comments were originally posted on a Health At Every Size email list and are posted here with her permission). Bacon's doctorate, by the way, is in physiology with an emphasis on weight management. She also has two master's degrees, in exercise physiology and psychology. She's a researcher herself, and the lead author on a study published in the Journal of the American Dietetic Association last year that found a non-weight-loss focused Health At Every Size program was far better for middle-aged "obese" women than a traditional weight loss approach.

OK, here's what Bacon has to say about the NEJM articles [emphases mine]:

In April 2005, Flegal et al., using a sophisticated modeling method respected for accuracy and data that included actual measurements on people nationally representative of today's population, determined that overweight predicted lower mortality risk than “normal” weight. These results were consistent with a large body of previous literature.

The backlash to[Flegal et al.'s] JAMA publication is not surprising. Fear-mongering about weight is worth billions to industry and consistent with government policy. Few stand to gain from the news that overweight is benign, if not beneficial.

NEJM’s recently published article entitled "Overweight, Obesity, and Mortality in a Large Prospective Cohort of Persons 50 to 71 Years Old" is clearly part of that backlash, heavy on sensationalism and weak on facts. Buried in their results is a conclusion completely consistent with that reached by Flegal et al.:In their words, overweight was not associated with increased risk of death for men, and only very weakly for women. (Indeed, even that conclusion is generous: the relative risk at the lower end of the "normal" category is similar to that found at BMI [Body Mass Index] 40 for men and 35-40 for women.)

Yet this conclusion is not prominent in the paper, nor does it show up in the abstract. Midlife gave them the results they were looking for and that’s what they chose to focus on. This despite the fact that their midlife data was drawn from a subanalysis which had an even smaller sample (now whittled down to about 5 percent of the sample that was sent surveys) and was based on recalled weight from over a decade previous. (That 40% of the sample chose to leave the question on recalled weight from a decade ago blank should give some indication of the ability of people to accurately remember and report this information.)

Their paper is weak for many other reasons:

1. They had a very low response rate (18%) from a sample that is not nationally representative.
2. Their data is based on self-report, which is known to be inaccurate. One only needs to look to their physical activity data to recognize the implausibility.
3. Even after limiting data to never smokers, there's till no increased mortality associated with overweight. The researchers hide this by using only the top )23-24.9) of the "normal" weight category as their referent group, while comparing it to the entire overweight group. Among never smokers the mortality risk in the normal weight category as a whole is the same as among the overweight category as a whole.
4. Adjustments for potential confounders were also weakly conducted: there is no data on fitness, only crude data on physical activity, and no consideration of other pominent potential confounders such as nutrient intake (other than alcohol consumption), weight cycling, or socioeconomic class.

This paper also demonstrated that people that lost weight had higher mortality, which is again consistent with previous literature. Why was this important information left out of the analysis?

Bacon went on to say that Paul Campos, author of The Obesity Myth, wrote an excellent Rocky Mountain News column about this issue. Read  Campos's article here.