Eating fat makes you fat

Fat packs more than twice as many calories as the other two main food forms (nine versus four per gram of protein or carbohydrate). Since your body uses less energy processing fat than the other food types, more of its energy can be stored as fat. Some fat is absolutely essential to good nutrition--but most people eat almost four times as much as they really need. You actually only need about 10 percent of your calories from fat to be healthy, but the typical American man´s diet is 35 to 40 percent fat.