"I'll diet tomorrow." That's strategy, not excuse, in Dr. James Johnson's The Alternate-Day Diet (April)—which lays out a plan for gorging one day, nibbling the next. (Think steak, red wine and ice cream on Sunday and yogurt, fruit and salad on Monday.) Pros: It prevents boredom, burnouts and binging. "No food is off-limits, so you don't feel deprived," says Leslie Goldman, The Weighting Game blogger. "The downside is that people might go wild on their 'up' days—this is not a license to eat chocolate cake for breakfast, lunch and dinner."

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