The girth of a nation

Wait. How do you know Jennifer Aniston and Brad Pitt's BMIs?

You can look up their height and weight on the Internet. And by the way, Jennifer Aniston is not extremely slender for a female celebrity, when you compare her to Gwyneth or Madonna who have BMIs of 16. Dr. Phil's BMI is 29.5. He's almost obese! I just discovered that he's 6-foot-4 and weighs 240. He's way at the very top of the overweight range and that's Dr. Phil -- America's big weight-loss guru.

So what is your gut reaction if I mention the word "Atkins"?

My reaction is that P.T. Barnum is spinning in his grave because he can't get in on this stuff.

It's safe to say that there is no more thoroughly investigated question in medicine than what happens when people restrict caloric intake for purposes of reducing weight: They lose the weight and gain it back again. It is absolutely amazing how impervious to evidence people are on these questions. It would be absurd at this point to ask whether cigarette smoking causes lung cancer. It's been investigated. Yes. It does. What happens if you have 100 people on Atkins is 95 of them one year later weigh as much or more than they did when they started. But there is something worse about Atkins, because low-carb dieting cuts aerobic endurance and since fitness level is vastly more important to health than weight, a diet that cuts fitness levels is perverse.

What about gastric bypass surgery?

Gastric bypass was first done back in the '60s, but it fell out of favor because it produced severe complications -- like death -- and there was no good data on long-term benefits. But it started coming back in a big way in the mid-'90s because of these laparoscopic procedures. They said the new surgery was much better than the old one. But what that meant was that it was much easier for surgeons. What happens inside the patients' bodies and the long-term consequences seem to be the same. There was a paper presented at the American College of Surgeons in Chicago that said in 60,000 gastric bypass surgeries, 1.9 percent were fatal within 30 days. This was in people who had surgery since 1990. And the rehospitalization rate was 20 to 30 percent. People claim that there was a higher mortality rate because these were morbidly obese people who were on the verge of death anyway. But most of these operations were on healthy women in their 20s for whom the regular risk of dying within the next year is one in 1,500. If 2 percent are dying after these operations, that's a massively increased mortality rate.

Who's most to blame for the weight hysteria you describe?

This is a society and a country fundamentally obsessed with weight loss and fundamentally eating disordered, and when those two things are in place everything else feeds into it. That's the reason people can sell 5 million dieting books even though dieting doesn't work. This kind of cultural hysteria gives us images of thinness that are wildly unrealistic but imbued with tremendous cultural power. There's no way to simply fix it. It's like saying -- and this is a dangerous but useful analogy -- what can you do about gender oppression? What can you do about racism? You can't implement one plan that is going to fix the culture, but I do think a very important first step is to recognize the existence of dissent.

Because I'm not saying it's not possible that the diet doctors are right. I'm just saying it's possible they're wrong. And if that's not investigated, they are just getting a free ride.

Your book points out that the rates of dieting continue to skyrocket even while the country's average weight had risen. Why?

The connection is causal. Dieting makes people heavier than they would be otherwise. There are a lot of studies where if you take two cohorts of people of the same initial weight and compare people who diet and people who don't, in the long term people who diet weigh more than the people who don't.

You argue in the book that all of this has to do with a culture of overconsumption.

Overconsumption in America is closely equated with class: The higher up you go the more you consume. The only area in which consumption is inversely related to class is caloric overconsumption. So the American elite project anxiety about the fact that they're massively overconsuming economically and materially through a disgust for fat, lower-class people.

America is just too big. We throw our weight around, our cars are too big, our shopping malls are too big, our houses are too big. Our anxiety about fat is our anxiety about our own bigness. But it's a projection that is so inappropriate when our cars weigh 700 pounds more than they did 15 years ago -- which is politically and economically and environmentally far more troubling than the fact that our bodies on average weigh eight pounds more than they used to 15 years ago.

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