Balance is the key to the Zone Diet. According to it creator, Dr. Barry Sears, eating an ideal ratio of carbohydrates to protein to fats is the key to weight loss. On the Zone Diet, dieters consume 40 percent of their calories from carbohydrates, 30 percent from protein and 30 percent from fats. Dieters eat five times a day, preferably before they get hungry, and low-fat protein sources are recommended. Meals should not exceed 500 calories and snacks should contain approximately 100 calories.