Not Clear Dr. Ruth Kava American Council on Science and Health Health and nutrition experts agree that saturated fatty acids in the diet can contribute to increased blood cholesterol levels. Increased blood cholesterol levels, in turn, increase the risk of heart disease. We humans consume TFAs when we eat meat and dairy products. Trans fatty acids are also formed when liquid vegetables oils are treated by a process known as hydrogenation. This process makes the oils both more stable and more solid at room temperature.
All oleomargarines are vegetable oils that have been hydrogenated to various degrees.
Such hydrogenated oils are used in many food products, among them cookies, cakes and fried fast foods. This new investigation of TFAs was performed at Tufts University s Human Nutrition Research Center on Aging. The Tufts researchers examined the effects that six diets containing varying amounts of TFAs had on the blood lipids of a small group of older people. In order to provide differing amounts of dietary TFAs to the subjects, the researchers designed a series of diets. Each diet derived 30 percent of its calories from fat, but the source of the fat differed in each diet.