A special advantage of soy protein is that it may help to lower blood cholesterol levels. When soy protein replaces protein from animal foods in the diet, cholesterol levels are reduced. The effect is best in people who already have high cholesterol levels. Over the past 30 years, more than 40 studies have shown the effects of soy protein on cholesterol levels. The fat in soybeans is mostly polyunsaturated.
Soybeans are low in saturated fat and, like all plant foods, contains no cholesterol.
Soybeans also contain a special type of polyunsaturated fat called omega-3 fatty acid. This type of fat is essential in the diet and may help to reduce risk for cancer and heart disease. Soybeans are one of the few plant foods that provide significant amounts of this fat. Many soyfoods are lower in fat than the whole soybean. Some brands of soymilk and tofu are also reduced in fat.