Association of dietary intake of soy, beans, and isoflavones with risk of cerebral and myocardial infarctions in Japanese populations: the Japan Public Health Center-based (JPHC) study cohort I.

Description

In this study of middle-aged Japanese subjects, the authors found a significant inverse association between soy and isoflavone intake with the risk of cerebral infarction and myocardial infarction (MI) in women but no association in men. Moreover, the inverse association was primarily observed in postmenopausal women. The authors also found a significant inverse association of soy intake with the risk of mortality for ischemic cardiovascular disease (CVD) in women. The authors propose many possible mechanisms to explain these associations, such as the antioxidant properties of soy isoflavones, which can reduce the formation of oxidized lipoproteins like LDL, as well as their hypocholesterolemic effects, their ability to lower blood pressure, and their estrogen-like effects on blood vessels. This study is compelling in that it is a large prospective study from a cohort of the Japanese general population, the authors examined the risk of stroke and MI incidence and mortality, and isoflavone intake was estimated using a validated questionnaire. In conclusion, the authors suggest that consumption of dietary isoflavones may be of benefit to postmenopausal women in preventing ischemic CVD.