Soy milk is a milk substitute made from soybeans. It is popular among lactose-intolerant individuals, as it does not contain lactose. It is also popular with some vegetarians and vegans. Soy has been extensively researched for its possible health benefits. One of the questions researchers have asked is whether soy can lower cholesterol.
Foods made from soybeans do lower LDL or the “bad” type of cholesterol, according to the Mayo Clinic. A 2007 article in the "Journal of the American College of Nutrition" found that drinking soy milk every day reduced the participant’s cholesterol by 5 percent, as compared to people drinking cow’s milk. The study also compared soy milk from whole soybeans and soy milk made from soy protein and found no difference related to cholesterol.
As well as lowering LDL cholesterol, soy milk may also increase HDL or “good” cholesterol. A Tulane University study, from 1982 to 2004, found that soy protein raised HDL levels while lowering LDL cholesterol.
One soy milk variety may affect cholesterol more than others, as it is specifically designed to do so. The Silk brand claims their “Heart Health” variety has soy protein and phytosterols, which both work on cholesterol. Silk conducted a study in 2008 on different soy milk combinations, with the result of a 6 to 16 percent reduction in LDL cholesterol. Specifically, they found the “Heart Health” soy milk lowered cholesterol in the participants by 7 percent. More research is needed on this subject, including independent research on this brand.
Even though research shows soy may lower cholesterol, some researchers believe that it is not a major impact. The Mayo Clinic cites the American Heart Association as saying soy foods reduce cholesterol minimally.
Foods from soybeans may improve cholesterol in a secondary way, by replacing higher cholesterol foods. For instance, if tofu from soy is used to replace meat, it could lower the cholesterol in your diet. In this case, soy milk as a replacement for cow’s milk might lower cholesterol, as 1 cup of cow’s milk has 24 mg or 8 percent of recommended daily intake of cholesterol. It also contains 5 g or 23 percent of saturated fat, which can turn into cholesterol. One cup of reduced fat cow’s milk still contains 20 mg or 7 percent of cholesterol and 3 g or 15 percent of saturated fat. 24 oz. of soy milk has 0 mg of cholesterol and only 0.5 g or 3 percent of saturated fat.