In the last decade, however, several leading nutritional scientists have begun to think Atkins may be partly right about carbohydrates, and scientists are now finally studying whether low-fat diets really work.

"I think it's quite clear that he's onto something important. It does seem that this substantial reduction in carbohydrate for many people does make it easier to control their diet over the long run," says Dr. Walter Willett, chairman of the department of nutrition at the Harvard School of Public Health.

Moreover, following the low-fat/high-carb diet of the U.S.D.A.Food Pyramid may not only make it difficult to control weight, it could actually be dangerous, according to Willett. "The dietary pyramid was out of date the day it was printed, but it's even more out of date given the evidence that's accrued since that time," said Willett. "We have good evidence now that the high intake of refined starches and sugars will increase risk of diabetes and heart disease," he added.

Years of diet studies done by Willett and others have apparently found that healthy people tend to do two things: They actually increase "good fats" and "good carbohydrates" while cutting down on both "bad fats" and "bad carbohydrates".

"And here is the big pay-off from a good fat/good carb diet. Not only is it more likely to be healthy, it may also make it easier to control our weight. That's because sugars and starches get quickly absorbed into our blood stream and lead to sudden spikes in insulin levels--which leads to low blood sugars and increased hunger, which make us eat more," said Johnson. That's why many experts now believe that a diet high in bad carbs actually increases the craving for food in people who are obese. "These people are actually hungrier that the rest of us. And they're hungrier because of the way they metabolize carbohydrates," said Taubes.