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Conquer Fat
By Sheryl Gay Stolberg, March-April 2003
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Many doctors regard Atkins as a quack and a self-promoter who, at best, preys on people desperate to lose weight and, at worst, promotes a high-fat diet that could be dangerous to the heart. But there has been growing evidence that a low-carbohydrate diet is effective in helping people lose pounds, at least in the short term.
Several small controlled studies do suggest that, during a span of a few months, eating a high-protein diet causes weight loss. The most recent is a 120-person study at Duke University Medical Center in Durham, North Carolina, which found that patients on the Atkins diet lost 31 pounds in six months, while the subjects on a low-fat diet recommended by the American Heart Association lost only 20 pounds. And while total cholesterol fell slightly in both groups, the levels of HDL, the good cholesterol, increased in only the Atkins patients.
The hitch: The Duke study was funded by a very biased source—the Atkins Center for Complementary Medicine. But the National Institutes of Health is taking serious notice: It's funding a five-year, 360-patient study of the Atkins diet, to be conducted by the University of Pennsylvania. The findings are expected in 2007.
Meanwhile, physicians are not about to recommend a high-fat, high-protein diet to obese Americans over 50. They know that almost all diets work at first, because they force people to focus on what they eat. "Where are all the Atkins alumni?'' asks Jules Hirsch, M.D., obesity researcher and professor emeritus at Rockefeller University in New York. Most of the ex-Atkins dieters he has seen, he notes, regained all their lost weight soon after they stopped the diet.
Willett, like many researchers confronted with the new studies, favors a compromise. He certainly doesn't advocate eating a diet heavy in red meat, but opts for fish and poultry, and says the unsaturated healthy fats like those found in nuts and olive oil can be healthy. What's more, he does recommend sticking to "low-glycemic" carbohydrates, such as oatmeal and whole-grain bread, which do not cause rapid spikes in blood sugar.
In treating older patients at the obesity clinic in the MedStar Research Institute in Washington, D.C., Atkinson adds a novel approach to the above advice: He writes each one a vegetable prescription. "I say, 'Your prescription is 12 servings of green vegetables a day. And if by 10 o'clock at night you still have eaten only four servings, you get a package of frozen spinach from the freezer and go gulp, gulp, gulp.' Twelve half-cup servings of vegetables is a huge amount of food, but only 240 calories. That's the same as five pats of butter."
The trouble with the diet-and-exercise regimen, of course, is that few people follow it. That's why doctors until recently regarded obesity as primarily a psychological problem, one brought on by a lack of will power. Today, scientists know that the problem is as much, if not more, physical in nature.
"What molecular biology has told us over the past decade is that there is a very complex regulatory system that controls body weight," says Rudolph L. Leibel, M.D., a molecular geneticist at Columbia University. More than 40 genes are likely to play a role in determining how much fat and muscle you carry on your frame, and subtle variations of several of these genes, acting together, could significantly affect your body weight, he adds. This knowledge has a new breed of obesity researchers toiling in the laboratory, untangling a complicated web of enzymes, hormones, receptors, and other chemical pathways that control hunger and metabolism.
"Appetite is biologically regulated; you feel hungry, and then you feel full. Those are all biological signals," says Steven Heymsfield, M.D., who runs clinical trials and treats overweight patients at St. Luke's-Roosevelt Hospital Center. "Eventually, we will know the source of those signals, and we will know how to change them.'' He and other researchers are convinced that effective drug treatments are imminent, and obesity, just like hypertension and diabetes, will soon be treated with pills. The pharmaceutical industry is spending millions to make it happen.
"There's a gold rush right now," says Heymsfield. Of course there is! Viagra was a billion-dollar blockbuster drug, but only about 10 percent of the male population has erectile dysfunction. In contrast, 64.5 percent of American adults and 15.3 percent of children are overweight.
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