Fat is a highly concentrated fuel that provides nine calories of energy per gram versus just four calories per gram from protein and carbohydrate. Fat in our diet provides essential fatty acids and fat-soluble vitamins and adds flavor to the foods we eat. Many people, including athletes, consume 40 to 50 percent of their calories in the form of fat by eating lots of meats, dairy products, and junk foods. A healthy diet calls for only 25 to 30 percent fat.The fats (or lipids) we commonly consume are called triglycerides. When we overeat, our body stores the excess energy in the form of triglycerides. When we burn fat, the triglycerides are taken out of storage and converted into glycogen for the muscles to burn as fuel. Fats are categorized as saturated fat, those found in foods from animals and palm and coconut oil, and unsaturated fat, those found mostly in plant foods. Athletes who have high fat diets should reduce their intake of saturated fat and trans fat because in many people these types of fat increase artery-clogging cholesterol levels. People can reduce saturated and trans fat intake by eating less red meat, milk chocolate (which contains saturated tropical oils), fried foods, and high-fat dairy products. When athletes reduce the fat they eat, they should replace the calories not with fat, oil, and sweets but with complex carbohydrate from grains, such as breads, rice, and oats. Because fat contains nine calories per gram and carbohydrate only four calories per gram, athletes will need to eat nearly twice the volume of complex carbohydrate compared to the fat they had been eating. If athletes are training extensively and consuming 4,000 or more calories per day, they may need to consume more unsaturated fat simply because they can’t consume the volume of complex carbohydrate to meet their daily energy needs. To improve athletes’ performance in endurance events, researchers have studied how to improve the ability of the body to burn fat during exercise. Athletes have tried carnitine, caffeine, and other supplements to improve fat metabolism, but the scientific evidence shows no benefits from these supplements in improving fat metabolism. As you’ll see in a moment, caffeine can be beneficial to sport performances, but not by increasing fat metabolism. Instead, the best way to improve fat oxidation during exercise is to improve the athlete’s level of fitness. Now that you’ve had a quick refresher on carbohydrate, protein, and fat, use table 16.3 as a guide to helping your athletes eat better. Consider placing this table in your player handbook and making a poster of it to display in the locker room. We’ll look at nutritional supplements next, and in chapter 17 we’ll look at pharmacological supplements when we consider drugs in sport.