John Foreyt, Ph.D., director of the Behavioral Medicine Research Center at Baylor College of Medicine in Houston.

Quick Fix: Eat 220-calorie breakfasts and lunches—a container of yogurt, a serving-size box of cereal, any food (preferably nutritious) whose label identifies exactly how many calories it contains. Then have a salad and small chicken or fish entrée for dinner. "It might get boring, but you're not going to hurt yourself with any plan that lasts just two weeks," says Foreyt, "and you'll see five or six pounds come off."

Long-term Goal: To segue into a controlled eating plan that has no snacks—which will seem luxurious after your 1,000-calorie-a-day boot camp.