Nutrition

The Skinny on Fat - What Kind of Fat and How Much Do We Need?

Readers often get confused and frustrated about the ever-changing nutrition information they read. But this is to be expected since new studies are continuously presenting newer findings. It is always recommended, however, to refer to reliable sources for health information. Because heart disease is the leading cause of death in the U.S., our government agencies and related science research organizations have recommended a low fat intake. A low fat diet can decrease the risk for obesity, hypertension, and insulin resistance. Obesity can also lead to diabetes, cancer (breast, colon, prostate), and gallbladder disease. As a result, many individuals think "no fat" is best, as we purchase margarine spreads, salad dressings, and similar foods.

The fats we eat provide us with essential fatty acids, which the body cannot produce, and are necessary for cell structure; kidney, liver, and reproductive function; growth; skin, hair; and wound healing. Fats in the diet provide calories for energy, transport fat soluble vitamins (A, D, E, K), regulate body temperature, and cushion internal organs. Fat also provides satiety and can add to the taste of food. Too much fat or the wrong kind of fat can influence blood platelet or clotting function and inflammation of the vessel wall which could lead to coronary heart disease. There are three kinds of fats in our food intake:

polyunsaturated fats: corn, cottonseed, safflower, sunflower, soybean, and sesame seed oils. Can decrease bad cholesterol (LDL), and increase good cholesterol (HDL).
saturated fats: animal fats, dairy fats, and coconut and palm kernel oils. Can increase LDL and decrease HDL.
monounsaturated fats: olive, canola, peanut oils, mustard oil, avocado, almonds, and macadamia nuts. Can decrease LDL and increase HDL.

We have been advised in recent years to consume more olive oil (monounsaturated fat) because it reportedly can decrease the bad cholesterol (LDL) and increase the good cholesterol (HDL). It has also been recommended to eat margarine rather than butter in order to avoid the cholesterol and saturated fat. On the heels of this recommendation came the finding that trans fatty acids were as damaging to our blood vessels as saturated animal fats. Trans fatty acids are formed when liquid polyunsaturated fats are hydrogenated to make stick margarine products and the like. This transformation from the cis to the trans molecular form changes the characteristics of the fat which then become more damaging to our blood vessels. The FDA has been considering indicating trans fatty acid content of foods on food labels, and recently The Virginian-Pilot came out with a supporting editorial of this newest label addition.

Other fatty acids getting attention are the essential linoleic (omega-6) and linolenic (omega-3) fatty acids. Some studies have shown that the omega-3 fatty acids are beneficial in actually decreasing the platelet build-up on the vessel wall, which would reduce the risk for blood vessel or heart disease. The best food sources of these omega-3 fatty acids are salmon, cod, albacore tuna, blue fish, mackerel, swordfish, shrimp, lobster, soybean, flaxseed oil, and canola oil.

In keeping all the above information straight and beneficial to you, it is recommended to:

Avoid excess saturated fat (buy/prepare low fat animal/dairy foods). The average weight- conscious female needs about 4 oz of meat, fish, cheese or chicken per day; the average weight-conscious male, about 6 oz.
Try to choose fish 2-3 times weekly.
Remember, cholesterol is only found in animal foods, not in plant foods. The label of plant foods
or oils may boast "no cholesterol," but could still be very high in fat.
Include small amounts of added fats (oils, margarines, dressings, etc.) from the polyunsaturated and monounsaturated family of fats with slightly more emphasis on the monounsaturated fats (olive, canola, peanut oils). Most of us are getting adequate polyunsaturated fat intake--it is the monounsaturated fat intake we may need to increase.
Small amounts of butter may not be harmful, but could contribute to the increased intake of
saturated fats, something most experts agree we're trying to avoid. Use spreads/margarines made with canola oil. If calorie counting, avoid adding no more than a few teaspoons of fat to your already low fat food at a meal.
When adding food labels, look for low fat food products or 3 grams fat per serving. Avoid buying foods with hydrogenated fats/oils in the first several ingredients listed on the label. Limit trans fat intake.
As long as the average fat intake over a week is reduced, some studies show a high fat intake
in one day may not be as harmful.

The two latest spread products added to the grocery shelf include Benecol and Take Control--both consist of canola oil. It has been reported that Benecol can lower LDL cholesterol by as much as 14%. The Center for Science in the Public Interest recently reported the results of a study that showed a Benecol-like margarine decreased the blood levels of the fat soluble vitamin beta-carotene. So, even though the food industry has provided us with progressive choices over the past several years, moderation in all things seems to still be the best advise.

As you can read from the above recommendations, going "fat free" may not be good for your health. We need a variety of small amounts of fats. Read as much as you can about these issues, and seek the counsel of a registered dietitian when in doubt.

Reprinted with permission of Port Folio Weekly - Health Monthly.