Brossura

ISBN 10: 0307949435 ISBN 13: 9780307949431

Casa editrice: Anchor, 2011

Persuasive, straightforward, and practical, Why We Get Fat is an essential guide to nutrition and weight management.
 
In this exciting new book, Gary Taubes, bestselling author of Good Calories, Bad Calories addresses the urgent question of what’s making us fat—and how we can change. He reveals the bad nutritional science of the last century and the good science that has been ignored, answering the most persistent questions along the way: Why are some people thin and others fat? What roles do exercise and genetics play in our weight? What foods should we eat, and what foods should we avoid?

About the Author:

Gary Taubes is a contributing correspondent for Science magazine. His writing has appeared in The Atlantic, The New York Times Magazine, Esquire, and The Best of the Best American Science Writing (2010). He has received three Science in Society Journalism Awards from the National Association of Science Writers, the only print journalist so recognized. He is currently a Robert Wood Johnson Foundation Investigator in Health Policy Research at the University of California, Berkeley School of Public Health. He lives in Oakland.

Excerpt. © Reprinted by permission. All rights reserved.:

INTRODUCTION

The Original Sin

In 1934, a young German pediatrician named Hilde Bruch moved to America, settled in New York City, and was “startled,” as she later wrote, by the number of fat children she saw—“ really fat ones, not only in clinics, but on the streets and subways, and in schools.” Indeed, fat children in New York were so conspicuous that other European immigrants would ask Bruch about it, assuming that she would have an answer. What is the matter with American children? they would ask. Why are they so bloated and blown up? Many would say they’d never seen so many children in such a state.

Today we hear such questions all the time, or we ask them ourselves, with the continual reminders that we are in the midst of an epidemic of obesity (as is the entire developed world). Similar questions are asked about fat adults. Why are they so bloated and blown up? Or you might ask yourself: Why am I?

But this was New York City in the mid- 1930s. This was two decades before the first Kentucky Fried Chicken and McDonald’s franchises, when fast food as we know it today was born. This was half a century before supersizing and high- fructose corn
syrup. More to the point, 1934 was the depths of the Great Depression, an era of soup kitchens, bread lines, and unprecedented
unemployment. One in every four workers in the United States was unemployed. Six out of every ten Americans were living in
poverty. In New York City, where Bruch and her fellow immigrants were astonished by the adiposity of the local children, one in four children were said to be malnourished. How could this be?

A year after arriving in New York, Bruch established a clinic at Columbia University’s College of Physicians and Surgeons to treat obese children. In 1939, she published the first of a series of reports on her exhaustive studies of the many obese children she had treated, although almost invariably without success. From interviews with her patients and their families, she learned that these obese children did indeed eat excessive amounts of food—no matter how much either they or their parents might initially deny it. Telling them to eat less, though, just didn’t work, and no amount of instruction or compassion, counseling, or exhortations— of either children or parents—seemed to help. It was hard to avoid, Bruch said, the simple fact that these children had, after all, spent their entire lives trying to eat in moderation and so control their weight, or at least thinking about eating less than they did, and yet they remained obese. Some of these children, Bruch reported, “made strenuous efforts to lose weight, practically giving up on living to achieve it.” But maintaining a lower weight involved “living on a continuous semi-starvation diet,” and they just couldn’t do it, even though obesity made them miserable and social outcasts.

One of Bruch’s patients was a fine- boned girl in her teens, “literally disappearing in mountains of fat.” This young girl had spent her life fighting both her weight and her parents’ attempts to help her slim down. She knew what she had to do, or so she believed, as did her parents—she had to eat less—and the struggle to do this defined her existence. “I always knew that life depended on your figure,” she told Bruch. “I was always unhappy and depressed when gaining [weight]. There was nothing to live for. . . . I actually hated myself. I just could not stand it. I didn’t want to look at myself. I hated mirrors. They showed how fat I was. . . . It never made me feel happy to eat and get fat—but I never could see a solution for it and so I kept on getting fatter.”

Like Bruch’s fine- boned girl, those of us who are overweight or obese will spend much of our lives trying to eat less, or at least eat not too much. Sometimes we succeed, sometimes we fail, but the fight goes on. For some, like Bruch’s patients, the battle begins in childhood. For others, it starts in college with the freshman twenty, that cushion of fat that appears around waist and hips
while spending the first year away from home. Still others begin to realize in their thirties or forties that being lean is no longer the effortless achievement it once was.

Should we be fatter than the medical authorities would prefer, and should we visit a doctor for any reason, that doctor is likely to
suggest more or less forcefully that we do something about it. Obesity and overweight, so we’ll be told, are associated with an increased risk of virtually every chronic disease that ails us—heart disease, stroke, diabetes, cancer, dementia, asthma. We’ll be instructed to exercise regularly, to diet, to eat less, as though the thought of doing so, the desire to do so, would never otherwise have crossed our minds. “More than in any other illness,” as Bruch said about obesity, “the physician is called upon only to do a special trick, to make the patient do something—stop eating— after it has already been proved that he cannot do it.”

The physicians of Bruch’s era weren’t thoughtless, and the doctors of today are not, either. They merely have a flawed belief system—a paradigm—that stipulates that the reason we get fat is clear and incontrovertible, as is the cure. We get fat, our physicians tell us, because we eat too much and/or move too little, and so the cure is to do the opposite. If nothing else, we should eat “not too much,” as Michael Pollan famously prescribes in his best-selling book In Defense of Food, and this will suffice. At least we won’t get fatter still. This is what Bruch described in 1957 as the “prevalent American attitude that the problem [of obesity] is simply one of eating more than the body needs,” and now it’s the prevalent attitude worldwide.

We can call this the “calories- in/ calories- out” or the “overeating” paradigm of excess fat—the “energy balance” paradigm, if
we want to get technical. “The fundamental cause of obesity and overweight,” as the World Health Organization says, “is an energy imbalance between calories consumed on one hand, and calories expended on the other hand.” We get fat when we take in more energy than we expend (a positive energy balance, in the scientific terminology), and we get lean when we expend more than we take in (a negative energy balance). Food is energy, and we measure that energy in the form of calories. So, if we take in more calories than we expend, we get fatter. If we take in fewer calories, we get leaner.



This way of thinking about our weight is so compelling and so pervasive that it is virtually impossible nowadays not to believe it. Even if we have plenty of evidence to the contrary—no matter how much of our lives we’ve spent consciously trying to eat less and exercise more without success—it’s more likely that we’ll question our own judgment and our own willpower than we will this notion that our adiposity is determined by how many calories we consume and expend.

My favorite example of this thinking came from a wellrespected exercise physiologist, a co- author of a set of physical-activity and health guidelines that were published in August 2007 by the American Heart Association and the American College of Sports Medicine. This fellow told me that he personally had been “short, fat, and bald” when he first took up distance running in the 1970s, and now he was in his late sixties and was “short, fatter, and bald.” In the intervening years, he said, he had gained thirty-odd pounds and run maybe eighty thousand miles—the equivalent, more or less, of running three times around the Earth (at the equator). He believed that there was a limit to how much exercise could help him maintain his weight, but he also believed he
would be fatter still if he hadn’t been running.

When I asked him whether he really thought he might be leaner had he run even more, maybe run four times around the planet instead of three, he said, “I don’t see how I could have been more active. I had no time to do more. But if I could have gone out over the last couple of decades for two to three hours a day, maybe I would not have gained this weight.” And the point is that maybe he would have anyway, but he just couldn’t wrap his head around that possibility. As sociologists of science would say,
he was trapped in a paradigm.

Over the years, this calories- in/ calories- out paradigm of excess fat has proved to be remarkably resistant to any evidence to the
contrary. Imagine a murder trial in which one credible witness after another takes the stand and testifies that the suspect was elsewhere at the time of the killing and so had an airtight alibi, and yet the jurors keep insisting that the defendant is guilty, because that’s what they believed when the trial began.

Consider the obesity epidemic. Here we are as a population getting fatter and fatter. Fifty years ago, one in every eight or nine Americans would have been officially considered obese, and today it’s one in every three. Two in three are now considered overweight, which means they’re carrying around more weight than the public- health authorities deem to be healthy. Children are fatter, adolescents are fatter, even newborn babies are emerging from the womb fatter. Throughout the decades of this obesity epidemic, the calories-in/ calories-out, energy-balance notion has held sway, and so the health officials assume that either we’re not paying attention to what they’ve been telling us—eat less and exercise more—or we just can’t help ourselves.

Malcolm Gladwell discussed this paradox in The New Yorker in 1998. “We have been told that we mus...