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Pamela Peeke, MD, a Pew Foundation scholar in nutrition and metabolism at the University of Maryland and author of Fight Fat After Forty, offers a slump-proof food plan (from 1,400 to 1,600 calories) to help the average 5-foot-4, 140-pound woman keep her spirits and energy high throughout the day. Basically, eat smaller meals and bigger snacks, avoid sugar sprees, and mix high-fiber or multigrain carbs with lean protein (especially soy, which is not only loaded with calcium but also helps ease symptoms of menopause) and only a little fat (preferably olive oil)—too much drags you down.

Breakfast: Unsweetened oatmeal (cooked with water or skim or soy milk) with cinnamon, raisins, blueberries, or a dollop of jam. Or a smoothie: soy powder with water or skim milk, and fruit.

Snack: Small whole wheat pita with two to three slices of low-fat or soy cheese melted in the microwave. Or a container of fat-free yogurt.

Lunch: Grilled fish or chicken on a bed of greens with a little dressing. (Use the real stuff—the fat-free spin-offs don't satisfy.) Or a vegetarian wrap.

Snack: A cup of soup or half a sandwich (tuna fish with a dash of vinaigrette, or turkey with mustard—hold the mayo) and a piece of fruit.

Dinner: Three to four ounces of chicken, fish, or beef, or a veggie burger. Salad or cooked vegetables. Twice a week, add one cup of brown rice or whole wheat pasta.

Snack: Fruit and fat-free yogurt or unbuttered popcorn.

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