The Skinny on Fat

Many of us are all too familiar with fat, but fat isn’t all bad. With nine calories in a gram, or more than twice the amount of a gram of carbohydrate or protein, it’s a concentrated energy source. It’s what your body burns at low levels of activity, such as when you’re sitting at a desk or walking easily. Fat supplies and transports some vitamins, helps to maintain nerve fibers and cell membranes, insulates you from the cold, and cushions internal organs.
In a good diet, 20 to 25 percent of your calories come from fat. This amount is less than most Americans eat—the average is 37 percent of calories from fat. Eating too much fat means that you’re not getting the carbs you need to restock your muscles from run to run. It’s also bad for your health because a high fat intake has been linked to heart disease and some cancers. And extra fat from your diet is easily stored as extra fat on you. If you emphasize getting 60 to 65 percent of your calories from carbohydrates, with plenty of fruits and vegetables in the mix, it will be easier to get your fat intake into the 20 to 25 percent range. Choosing lean cuts of protein, such as white chicken meat instead of a greasy cheese steak sub, also helps.