“Kolata commands the intelligent curiosity, well-honed reporting techniques and smooth prose style of a top science reporter.” —Beryl Lieff Benderley, The Washington Post

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Looking for Diets in All the Wrong Places

If you met Carmen J. Pirollo, you might not realize that he has a weight problem. He’s a square-jawed, animated man, who talks in exclamation points, favors preppy clothes, and—the big hint that he’s a bit self-conscious—sometimes doesn’t tuck in his shirts. Yet while you may notice his abdomen under that shirt, he is not what you might think of as obese. He does not seem to have any trouble moving, and when he sits down, he does not spill out of his chair. He’s not like one of the subjects in those insulting, deliberately humiliating photos that show up in magazine articles or on television programs to illustrate the horrors of the obesity epidemic—those familiar images of round-faced, double-chinned people captured stuffing hamburgers into their mouths or of a fat family lumbering past fast food restaurants, dipping into bags of popcorn or licking ice cream cones.

But Carmen, according to the official standards, is fat—obese, in fact—and he knows it. He’s 5 feet 11 inches tall, and at 265 pounds, his body mass index, a measure of body fat based on height and weight, is 37. That is a level at which public health guidelines warn that dire health risks start to mount.

And dieting has become a part of Carmen’s life. Over the years, he has tried almost every variation on the dieting theme, losing weight over and over again, only to gain it all back, and more. "I’ve lost a whole person over my lifetime," he says. In his thirty-two years of professional life as an elementary school teacher at a New Jersey school not far from his townhouse in Philadelphia, he has seen his weight climb and climb and climb despite all his efforts to control it.

But on a chilly evening on the first day of March in 2004, Carmen, at age fifty-five, opened a new chapter in his weight loss history. He began a two-year stint as a volunteer in the extraordinary experiment that was prompted by the small pilot study a few years earlier comparing the Atkins diet with a standard low-calorie one.

The three investigators who did the first study got federal funding to expand it to include 360 obese subjects at their medical centers—the University of Pennsylvania, the University of Colorado, and Washington University in St. Louis—and continue it long enough to get some answers that would hold up to scientific scrutiny. They’ll follow each subject for two years, with regular measurements of weight, blood pressure, kidney function, and stamina. They’ll periodically question their subjects about satisfaction with the assigned diet, and they’ll evaluate the dieters for changes in mood.

The two diet plans could not be more different. The low-calorie diet program is one that few dieters have heard of but that is beloved by academic researchers. It was developed by a member of the club, a university professor, not some self-promoting diet doctor, but a researcher, a psychologist whose goal was to give the best advice for weight loss, whether or not it was what fat people wanted to hear. And it comes with a hefty manual that tells you how to succeed, culling the accumulated wisdom of academic researchers. The diet’s name is as earnest as its advice. LEARN, it’s called, which is an acronym for "Lifestyle, Exercise, Attitudes, Relationships, Nutrition." And it was the diet with which Atkins would be compared.

Of course, no one signing up for the new study wanted the low-calorie LEARN diet. They were attracted by the idea of a two-year intensive program to help them lose weight and keep it off. They knew their diet, Atkins or low-calorie, would be decided at random. But they were hoping they would get Atkins, the diet that all America at that time, it seemed, was adopting. The Atkins diet was developed by a man so confident in his program that he called it "the new diet revolution."

The Atkins diet plan says that carbohydrates make you fat, so you must strictly limit them. But you can eat your fill of other foods. You will be counting grams of carbohydrates, but how hard is that when you can fill up on foods like steak and eggs? Also, Atkins promises, you won’t be hungry. No more going to bed at night feeling famished, hardly able to wait for the next morning when you can eat again. No more obsessing over the next meal, feeling a gnawing hunger even as you finish your meager allotted portions of the meal you are eating. His diet, Atkins stressed, was nothing like those food-deprivation diets that almost everyone who struggles with their weight has tried and tried again. His diet really was a program you can happily follow for the rest of your life. "With Atkins, you’ll get the results you’ve dreamed of without the agony of deprivation," he insists.

LEARN’s message is that if you want to lose weight, you have to face up to a punishing reality—you probably will never be eating your fill, and you will always be keeping track of what you are eating and how much. You will always feel that edge of hunger. But the program will teach you how to manage. You will learn to monitor your food, and to stop eating before you are sated. You will learn tricks, like putting your fork down between bites of food, that will slow you down and help you eat less. You will learn to recognize portion sizes: what a 4-ounce piece of steak looks like, or a medium apple, or a 1-ounce slice of bread. And that training will stand you in good stead for the rest of your life as you try to keep your eating under control. "Let’s face it—losing weight is hard work and maintaining weight loss can be even more challenging," the LEARN manual bluntly says.

Atkins says that carbohydrates are diet traps, making you put on weight despite yourself. If you greatly reduce the amount of carbohydrates you eat, he promises, your body’s metabolism will change so you start burning your own fat for energy and you lose weight.

LEARN says that the source of your calories is not the issue—it is how many you are eating that matters. Consuming too many calories is what makes you fat, and if you want to lose weight, you have to count them rigorously every day. There are no forbidden foods, but your goal is to eat healthfully, so you are to choose foods consistent with the U.S. Department of Agriculture’s food pyramid while keeping careful track of your calories. That means keeping a food diary, weighing and measuring what you eat, and choosing foods that are low in fat. It means a diet that emphasizes fruits, vegetables, grains, and cereals.

The advice embodied in LEARN is pretty much what has been urged upon Americans for decades, yet it is advice that few have followed. STRIVE FOR 5 say the cheery signs in Wegmans food markets, a chain of supermarkets in the Northeast, exhorting customers to eat five or more servings of fruits and vegetables each day. But if you just turn your head, you will see the warm loaves of bread piled behind the bakery counter, the cheese breads and oil-coated focaccias next to the long loaves of French bread, which, as almost every dieter knows, are made without fat. And scattered about the aisle of apples— thin-skinned red McIntoshes, next to speckled Cameos, next to shiny green Granny Smiths, next to a pile of ovoid Pink Ladies—are little plastic pots of caramel dip. Life is hard for the resolute.

But the LEARN program was never supposed to be the academics’ answer to fad diets that promise miracles. It began about as modestly as a diet can, as part of a Ph.D. dissertation by a young psychology student at Rutgers, New Jersey’s state university. The year was 1976, and the student, Kelly Brownell, was testing the hypothesis that dieters would be more likely to succeed if their spouses got involved wit