5. Choose foods with staying power.
Fill up on wholesome, fiber-rich, water-filled foods like vegetables, fruits, whole grains and beans, which fill you up faster for longer on fewer calories. And how you eat is as important as what you eat. A growing body of research shows that the best way to keep your metabolism revved and body-fat levels low is to feed yourself in small amounts. Eat airline-size (rather than restaurant-size) portions of meat, fish, pasta, grains and desserts. And eat every three to four hours, for a total of five mini-meals per day.

6. Enjoy food.
You're much more likely to stick with a diet if your food looks, tastes and smells delicious. Feeling deprived will only backfire. Make a plan you can live with by livening up food with herbs and spices like basil, cilantro, curry and ginger; aromatic veggies like garlic and onions; and condiments like mustard, hot pepper sauce or salsa. Experiment with new foods: Tantalize your taste buds with two new fruits or vegetables at each meal. Try different cold/hot cereals and breads. Don't declare high-fat favorites "off limits"; savor them in small amounts.

7. Strive for balance.
For energy, satisfaction, staying power and good health, aim to eat a healthy balance of protein (15-20 percent of your total daily calories), fat (less than 30 percent of your total daily calories) and carbohydrate (50-55 percent of your total daily calories) each day. Rule of thumb: Fill three-quarters of your plate with plant foods, leaving the rest for small amounts of fish, nonfat milk products and nuts or seeds.