Concentrate on carbohydrates.
Bread, rice, pasta, cereals, fruits, and vegetables are your body's primary sources of fuel and should provide more than half of your daily calories. Try to have at least nine servings of whole-grain foods, four servings of vegetables, and three servings of fruits to give you not only energy but also fiber, vitamins, and minerals. Instead of grabbing a candy bar, satisfy your sweet tooth with fruits that are rich in vitamin C, such as oranges, berries, and melon. Also, vary your vegetable choices to include those that are dark-green and leafy (spinach, broccoli), deep-yellow or orange (carrots, sweet potatoes), and starchy (potatoes, corn).