For "Jane Doe", who weighed more than 200 pounds, success finally came with another low-carb diet--The Zone--based on a finely controlled balance of good carbs, good fats and lean protein. "I felt that this worked better than any of the other diets I had tried. And I've been eating this balance (40% carbs, 30% fats, 30% proteins) now for four years. I lost 90 pounds of fat," Doe said. "Your blood sugar levels never go too high and never fall too low, but they fall in this nice moderate zone."

But are low-carb diets right for everyone? Experts agree, there's only one way to prove for certain that low-carb is better than low-fat, and that's with a long-term, randomized clinical trial. Leading obesity researcher Dr. George Blackburn of Beth Israel Deaconess Hospital in Boston had funding from the Atkins Foundation for such a trial, which will compare a traditional low-fat diet with a modified Atkins diet that emphasizes good fats.

We don't know whether he's right or not, but at least you know both the National Institutes of Health and the Atkins Foundation are interested in finding out," Blackburn said. "In the meantime, there's plenty of compelling evidence to do the following," advised Johnson. "Get rid of the refined starches and more vegetables and fruit, eat lean protein and healthy fats. You'll lose weight and feel better and may reduce your risk for heart disease."