The girth of a nation

Do you base your argument on what you found in studies, or have you also reported out this hysteria by talking to people in the weight-loss field?

I started out by reading studies and again and again ran into the same phenomenon: There was this disjunctive experience of reading the data and not being able to understand how conclusions about the correlation between weight and health stemmed from this data. I soon found people who were willing to say flat-out, "The reason you're having that experience is because those conclusions don't flow from that data."

I asked a very prominent epidemiologist at the CDC [Centers for Disease Control] about the latest study that came out in March, claiming that 400,000 deaths a year are a result of poor diet and a lack of activity level. I asked her how accurate that number was, and off the record -- because she wants to keep her job -- she said, "I think it's pretty accurate with a margin of error plus or minus 400,000 deaths a year."

The whole thing makes as much sense as reefer madness or hysteria over satanic ritual abuse in our day-care centers. People can look back at eugenics or something and say that that was ridiculous. Nevertheless, if they see something about an obesity epidemic on the front page of the New York Times and you ask them to consider the possibility that it's not true, they'll say how can you possibly question it when the NIH [National Institutes of Health] and CDC are telling you that it's true?

What is your reaction to the commonly held belief that there is a direct connection between obesity and ill health?

Something which ought to cause tremendous skepticism but hasn't is when you hear there is an epidemic of obesity in the U.S. According to official government standards, you're overweight if your BMI [body mass index] is over 25, which is 64.5 percent of the population on the basis of available data. Then there are the people at Harvard Medical School who think everyone should have a BMI of under 22 when 80 percent of the population is at 22 or higher. So according to all of them, the large majority of the population weighs too much. But there should be suspicion about the claim that there is a strong causal link between heart disease, hypertension, cancer -- and weight. Because these diseases are less prevalent and less fatal than they were even recently. Cancer rates continue to fall. Americans are much healthier now and have a longer life expectancy than they ever had before.

Studies about the causal relationship between these diseases and obesity fail to take into account a host of other factors, including socioeconomic status, activity levels, fitness levels, dieting, weight cycling, and diet-drug use, which all have an impact. If you take those factors into account you see how weak the argument is that a certain level of BMI is in and of itself causing heart disease, hypertension or cancer.

What about Type 2 diabetes?

Diabetes is a separate and special case because in the case of Type 2 diabetes, there is a strong correlation between weight and the condition.

But the big killers are heart disease and cancer, and there is a weak correlation between an increased BMI and those diseases. The level of physical fitness that needs to be maintained to see health improvements is the equivalent of a half-hour walk every day. And people who are profoundly sedentary -- without regard to weight -- are at greater risk than obese people with that level of fitness, who are very healthy, regardless of how much they weigh.

But isn't the idea of physical fitness -- walking a half-hour a day -- related to losing weight?

The evidence is very powerful that improved health among people who go from being sedentary to active is not due to weight loss, because for most people, increased physical activity does not produce significant long-term weight loss. And people who lose a lot of weight don't get any benefit over people who lose a little weight, so the benefit of weight loss by itself is medically nonexistent. But the good news is you don't have to become thinner to enjoy significantly improved health.

And you argue that the people telling us that we can get thinner aren't necessarily living by their own imposed guidelines?

I was at this Time/ABC obesity summit three weeks ago and [Secretary of Health and Human Services] Tommy Thompson is talking about how terrible this epidemic of obesity is -- and he's not a slim guy. He's definitely obese by the standards he wants to impose. I was the lone dissenter, and there are tons of people out there questioning the war on obesity but they didn't invite any of them. They invited only the pain in the ass lawyer who's more easy to dismiss, because I'm not a medical professional. But one of the things I said is that all these people -- most of them men -- are overweight, or even obese by their own definitions.

I've really reached a wall of ideological incomprehension: How is it that people whose own bodies literally embody a refutation of their claim can keep getting up and haranguing us for being obese? What would people say if Tommy Thompson got up and lit up a big old fatty and then told all of us how terrible marijuana is? I assume people would say that doesn't seem to make a lot of sense! But literally no one ever says, "Well, wait a second, Mr. Secretary ... how much do you weigh?" A central component of the whole obesity myth is that people could weigh significantly less if they wanted to, but these people at the forefront of the war on fat don't.

Next Page: How much of our obsession with weight loss is about the desire to look like Jennifer Aniston?

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