Fat

Fat, a member of the lipid family, is the most concentrated form of energy in all living things; it has more than twice the calories of protein or carbohydrates. The human body – like other mammals – is designed to turn virtually all its excess dietary calories into fat and store it as a energy reserve.

Fat provides insulation for the body and padding around sensitive internal organs. Several nutrients are found in fat, including vitamins A, E, and K, and the essential fatty acid. When eaten, fats slow the rate at which the stomach empties, causing a feeling of fullness and satisfaction. And let us not forget a most important quality, namely that fat contributes some of the most wonderful tastes and textures in our food.

The individual fatty acids resemble chains ranging in length from 8 to 25 links. Fats come in three basic types: saturated, monounsaturated, and polyunsaturated. The fat and oils in our diet are made up of different proportions of these three types.

Fat sources that are primarily saturated are found in animal products such as butter, lard, eggs, meat, and poultry. Vegetable sources that contain a high proportion of saturated fat include coconut oil, palm oil, palm-kernel oil, and cocoa butter.

Oils that are primarily monounsaturated include olive oil, canola (rapeseed), almond, avocado, and peanut oils.

Polyunsaturated fat is found in the oils of seeds and some nuts, including corn, soy, safflower, sesame, and walnut. Fish oils also contain relatively high concentrations of polyunsaturated fat, making them unique in the animal world. Polyunsaturated fat is the only type of fat known to be required by the body.

Does Our Fat Intake Increase the Risk of Disease?
There's been a great deal of mudslinging in the fat arena, so if you are bewildered by the roles and risks of fats, you're not alone. There is nothing inherently "wrong" with fat, but scientific studies have found a strong association between an overconsumption of fat and the risk of developing our most troublesome health problems, including heart disease and cancer.

One explanation is that fats have a nasty tendency to react and become "oxidized," turning into compounds that can lead to heart disease, cancer, and other degenerative diseases. The higher one's fat consumption, the greater the risk. Moreover, our bodies have a defense system that can prevent this from happening. Our defenses depend on a healthful diet that contains plenty of antioxidant nutrients. These nutrients, found in vegetables, fruits, and grains, include vitamins A, E, and C, and the carotenoids, as well as a wide variety of naturally occurring plant compounds (phytochemicals) found in whole foods. Scientists are only beginning to understand what it is about healthful foods that make them so good for us.

Consider also that in other countries, such as those in the Mediterranean, people consume higher levels of fat and yet they have health statistics that put Americans to shame. The answer is that their diet focuses on fresh whole foods.

It is also important to stay away from processed food fats that are made via partial hydrogenation, the process by which a vegetable oil is changed from a liquid oil to a semisolid fat. Partial hydrogenation does more than harden the oil, it creates trans fatty acids, a type of aberrant fat that is linked to major diseases such as heart disease and cancer. You will find partially hydrogenated oils in shortening, nondairy creamers, stick margarines, snack foods (such as doughnuts, chips, and pastries), and deep-fried foods (such as french fries). If there is one fat to avoid entirely, this is it. Read the ingredient statement on the food label to find out whether it is present.

The more you understand about the key players in the fat saga, the greater your appreciation for the need to emphasize fresh fruits, vegetables, grains, and nuts. With this style of eating. you give your body the antioxidant nutrients it needs to protect itself.

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Excerpted from:

From The Nutrition Doctor's A-to-Z Food Counter. Copyright © Ed Blonz, 1999. Used by arrangement with NAL Signet, a member of Penguin Group (USA) Inc.

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