Unsaturated fatty acids are derived mostly from plants, and nearly all vegetable oils, with the exception of tropical oils, are unsaturated. Olive, canola and peanut oil are the three most widely used oils that are high in monounsaturated fatty acids. Rice bran oil, widely used in Japan and available in some U.S. stores, also is high in monounsaturates and quite healthy, Dr. Radcliffe said. Polyunsaturated fatty acids also are healthy and like monounsaturates, reduce LDL cholesterol. Safflower, soybean, corn, cottonseed and sesame oil are high in polyunsaturated fatty acids.
All oils contain a mix of saturated, monounsaturated and polyunsaturated fatty acids.
Vitamin E In addition to its cholesterol-lowering capabilities, cottonseed oil has the highest amount of vitamin E of any vegetable oil, with the exception of almond oil and wheat germ oil. Vitamin E is thought to play a protective role against many diseases, including cardiovascular disease and prostate cancer. Recent research suggests it may help prevent memory loss, and Alzheimer's patients are usually placed on mega doses of vitamin E. But getting enough vitamin E in a normal diet is not easy, said Dr. Radcliffe, especially since the recommended dietary allowance, or RDA, was recently doubled by the Institute of Medicine's food and nutrition board. The board now recommends 15 milligrams a day for everyone. Most U.S. residents consume only about 40 percent of the RDA for vitamin E, and statistics from the Centers for Disease Control show African-Americans and Hispanics have particularly low vitamin E intakes.