Nutrition Science and Everyday Application - beta v 0.1

THE FUNCTIONS OF FATS 255
In addition to improving bioavailability of fat-soluble vitamins, some of the best dietary
sources of these vitamins are also foods that are high in fat. For example, good sources of
vitamin E are nuts (including peanut butter and other nut butters), seeds, and plant oils such
as those found in salad dressings, and it’s difficult to consume enough vitamin E if you’re
eating a very low-fat diet. (Although fried foods are usually cooked in vegetable oils, vitamin
E is destroyed by high heat, so you won’t find a lot of vitamin E in french fries or onion rings.
Your best bets are minimally-processed, whole foods.) Vegetable oils also provide some
vitamin K, and fatty fish and eggs are good sources of vitamins A and D.
Contributing to the Smell, Taste, and Satiety of Foods
Fats satisfy appetite (the desire to eat) because they add flavor to foods. Fat contains
dissolved compounds that contribute to mouth-watering aromas and flavors. Fat also adds
texture, making baked foods moist and flakey, fried foods crispy, and adding creaminess
to foods like ice cream and cream cheese. Consider fat-free cream cheese; when fat is
removed from the cream, much of the flavor is also lost. As a result, it is grainy and
flavorless—nothing like its full-fat counterpart—and many additives are used in
an attempt to replace the lost flavor.
Fats satisfy hunger (the need to eat) because they’re slower to be digested and absorbed
than other macronutrients. Dietary fat thus contributes to satiety—the feeling of being
satisfied or full. When fatty foods are swallowed, the body responds by enabling the
processes controlling digestion to slow the movement of food along the digestive tract,
giving fats more time to be digested and absorbed and promoting an overall sense of
fullness. Sometimes, before the feeling of fullness arrives, people overindulge in fat-rich
foods, finding the delectable taste irresistible. Slowing down to appreciate the taste and
texture of foods can give your body time to send signals of satiety to your brain, so you can
eat enough to be satisfied without feeling overly full.