Illustration: Edwin Fotheringham

Low Carb and Exercise

A low-carb diet consistently produced the greatest weight loss in the first six months of dieting, so this plan—combined with exercise—seems to be a good place to start. "I'm a proponent of that approach if it means you'll eat fewer junky carbs," says Christopher Gardner, PhD, associate professor of medicine at Stanford University and lead author of the study in Match 2 (above ). But Gardner says dieters may need to try more than one plan before they find success. "We are all so different—a diet that works for me may not work for you," he says. In fact, each of the diets had a few adherents who managed to lose 30 to 40 pounds. "What's more important than diet type is how closely you can adhere to it," says Gardner.

The truth is, says Meir Stampfer, MD, of the Harvard School of Public Health and an author of the Match 1 study, "there is more than one way to go for weight loss, so don't get discouraged."