The Zone diet is a high-protein, low-carbohydrate, fat-controlled eating plan. It is not as restrictive as other high-protein diets and it allows for a broad range of foods to be consumed. A small amount of protein is combined with twice the amount of "favorable" carbohydrates, including fruits and vegetables. If choosing "less desirable" carbohydrates, the portion size is smaller. Sears' Zone diet is based on the theory that the human body is genetically programmed to reach peak efficiency when all meals, including snacks, consist of a set caloric ratio of carbohydrates, proteins, and fats. The diet recommends an intake of 40% of calories from carbohydrates, 30% from protein, and 30% from fats (40-30-30). When this ratio is achieved, the body is working within the "zone." The body will have maximum energy and weight loss.