The Soybean and Cardiovascular Health
Coronary heart disease (CHD) is the major cause of death in most developed countries and the roles of lifestyle and diet in its genesis are undeniable. The soybean has been under intense investigation as having protective effects on cardiovascular health. This legume, a staple of most Asian diets, has received attention from both health care providers and researchers because of its excellent nutritional profile and unique non-nutritive component. Animal and human studies have shown that consumption of soy food products is cholesterol-lowering, and there is also evidence of protective effects directed at later events in the atherosclerotic process. The protein, lipid and carbohydrate components are likely responsible for soy’s hypocholesterolemic effects. Modulation of later events in atherogenesis, e.g., lipoprotein peroxidation and cell signalling pathways, may be mediated by the isoflavones, non-nutritive phytochemicals unique to the soybean. These diphenolic compounds are also of interest because of their structural similarity to the hormone estrogen, an important player in many chronic diseases of multifactorial etiology (CHD, cancer, osteoporosis, etc.) that affect women. While the need for further investigation is warranted, particularly that directed at elucidating mechanisms of action, the evidence at this point for the hypocholesterolemic and anti-atherogenic effects of the soybean and soy food products is convincing and attempts should be made to better incorporate this food into the American diet.