The Healthy Diet »

No fat is also an important source of energy. Like a carbohydrate a molecule of fat is composed of carbon, oxygen and hy­akwis, though they are linked together in a different way. The body extract energy from fat by oxidizing it — combining the hy­in fat with the oxygen that you breathe to form water, which the energy that held the hydrogen in the fat. This complex clot only depends on oxygen, but is also helped along with the formed when carbohydrates release energy. As a result, it difficult for your muscles to use fat for energy without the of carbohydrates.

In addition, whereas producing energy from fat always requires energy production from carbohydrates can continue briefly oxygen. For that reason, only carbohydrates can provide the for short bouts of all-out exertion, when you are not breathing oxygen to burn fat.

During a longer period of exercise that calls for endurance, carbohydrates ­supply about half the body's energy, while fat and, to a small? protein supply the other half. In fact, when exercise extends 60 minutes, fat may provide 80 percent or more of your energy but your body still requires carbohydrates to use the fat. contributes very little energy; rather, it is the chief material budding all of your body parts, including the muscles, skin, tendons, ligaents, blood cells and brain cells.

By weight the energy value of carbohydrates and protein in food is the same — four calories per gram. Fat yields nine calories per gram. a gram of fat, therefore, requires more than twice as much activity, and any excess calories that are not used in supplying me stored as body fat.

How are carbohydrates, fats and protein best distributed in a healthy diet?
If you divide the food you eat each day into its component macronutrients proportion of the total calories available from each should 55 percent from carbohydrates, 15 percent from protein and 30 percent from fat. These percentages are based on guidelines diet established by the American Heart Association, the National Academy of Sciences and the National Institutes of Health. To stay within these guidelines, it is obviously helpful if you are aware of the nutritional make-up of the dishes you are eating. Such information accompanies every recipe in this book. But reduced to its most basic elements, your diet will very likely be healthy if you avoid foods that are high in fat and refined sugar and eat mostly those that are high in complex carbohydrates.

What is the best sweetener? Molasses can contribute sign#kant4y to your daily mineral intake supplying some iron. Most other sweeteners, including honey, do not contain much of anything except empty calories. One advantage of cooking with, honey, however, is that it is sweeter than hefted sugar. In some recipes, you can add less honey than you would sugar and create desserts that contain fewer calories.

What is so special about complex carbohydrates?
All carbohydrates are sugars, but they come in different sizes and nutritional packages. Refined or processed foods such as candy, cookies, jams and many soft drinks contain mostly the simple sugar called sucrose. These foods are dense in calories but offer little else in the way of nutrients. If consumed in more than modest quantities, they provide more calories than the body can burn up and the excess is converted into fat.

Complex carbohydrates are made up of chains of sugars that form the starches in a wide variety of plant foods, including such common foods as potatoes, pasta, bread, rice and corn, and a variety of vegeta­bles and legumes. When digested, the sugar chains in complex carbo­hydrates are broken into simpler sugars. But unlike many foods that are loaded with sucrose, foods high in complex carbohydrates are usually rich in vitamins and minerals and may contain protein as well. Many of these foods also have appreciable amounts of water and indigestible fiber. Gram for gram, then, foods that are high in complex carbohydrates are almost invariably more nutritious and less fattening than sugar-laden foods. Fruits contain the simple sugar fructose, but they also contain the vitamins, miner,-As and fiber that many processed foods lack.