Salmon What a catch! Research suggests the omega-3s in salmon and other fatty fish help build muscle—and the more muscle you have, the more calories you burn. Omega-3s may also help reduce fat storage by lowering cortisol levels (scientists have yet to confirm how). Go for: Two 3-oz servings of fatty fish per week.
Yogurt Calcium-rich foods have slimming superpowers. Get too little of this mineral and your body's more likely to pack away calories as fat, according to a review of studies. With up to 50 percent more calcium per ounce than milk, yogurt is a potent source. Better yet, its probiotics may help keep belly fat under control. Go for: At least two servings a day.
Avocado For a speedy metabolism, you need to keep inflammation in check and blood vessels clear and supple. Avocado's unique combo of essential fatty acids, monounsaturated fats, and antioxidants helps you do just that. Plus, one avocado's 14 grams of fiber kicks up your calorie burn. Go for: One to two daily servings of foods high in healthy fats.
Beans High in resistant starch and fiber, beans force your system to use extra energy (as in calories) to break them down. Research from the University of Colorado suggests that if you choose foods high in resistant starch—it's also found in whole grains and not-quite-ripe bananas—you can increase your calorie-burning power by up to 24 percent over the course of the day. Go for: One serving of a resistant-starch food per meal.
Chili Peppers Feel the burn? It's more than mere sensation: chilies' heat signals the presence of capsaicin, a compound that, along with capsiate, can propel the body to scorch an extra 50 to 100 calories following a spicy meal. Go for: Chilies as hot as you can stand. (But watch out! The hottest ones—habanero, Scotch bonnet, and Thai or Indian peppers—are too fiery for many people.)