Hundreds of new diet books hit the shelves each year promising -- at last! -- the real secret to losing weight and keeping it off. And each year, more and more Americans join the ranks of the overweight and obese.
Why don't diets work? Recent studies show that many popular diets, even radically different diets, actually do help people lose weight -- for a while. Whether they follow a low-fat/high-carbohydrate regimen or a low-carb/high-protein one, most people shed pounds for about the first six months. Then the weight creeps back.
Editor's Note: Food Pyramid Replaced
In June 2011, the USDA replaced the food pyramid with a new plate icon.
By the end of a year, many people are right back where they started from.
Why Fad Diets Fail
One reason fad diets fail is that they are hard to stick with. Dieters end up having to say no to too many foods they like. Another problem is that many popular diets are nutritionally unbalanced.
"If a diet is too low in carbohydrates, you can end up deficient in fiber and B vitamins," says Connie M. Weaver, PhD, a professor of nutrition at Purdue University who has played a key role in shaping federal nutrition guidelines. "If it's too low in fat, you won't get enough fat-soluble vitamins and essential fatty acids."
Nutritional deficiencies pose health dangers. And they may also be one reason many people overeat. If a diet doesn't contain all the nutrients the body needs, some researchers speculate, people go on eating -- and overeating -- until they get them.
What's a dieter to do? The real secret to safe, effective, and nutritionally sensible way to lose weight, more and more experts say, can be found in the familiar but often overlooked USDA diet pyramid.
The Power of the Pyramid
The food pyramid, which made its debut in 1992, offers a visual distillation of the best consensus on nutrition advice for the general public. Sure, there have been controversies over the years. And the pyramid has changed to reflect evolving nutrition science.
"But many nutritionists agree that the official food pyramid represents the most scientifically sound approach to eating for good health," says Susan Krebs-Smith, PhD, chief of the risk factor monitoring and methods branch at the National Cancer Institute, who recently reviewed MyPyramid's advice.