The case for soy as a cure-all continues to be called into question. In August, we looked at a study that found no link between soy supplements and decreased menopausal symptoms. Now, a study published in Stroke has found that taking soy supplements did nothing to decrease hardening of the arteries in otherwise healthy post-menopausal women.
Acting on the observation that the rate of cardiovascular disease is lower in Asia, where diets are high in soy, researchers at the University of Southern California s Keck School of Medicine randomly assigned the 350 healthy postmenopausal women in their study to receive either 25 grams of soy protein or soy-free milk protein each day. Over the course of three years, on a bi-annual basis, researchers used an ultrasound to measure the build-up in the women s carotid arteries (those which supply blood to the brain). Ultimately, however, there was no significant difference between the artery thickening in the two groups.
The authors explain their findings by noting that isoflavones, the estrogen-like chemicals in soy, are less likely to affect post-menopausal women, whose bodies seem to become less responsive to estrogen the further away from menopause they get.
This sounds like a reasonable study, says ACSH's Dr. Ruth Kava. It really just doesn t appear that soy supplements provide any special benefit to post-menopausal women. Clearly, women need to take other measures to reduce their risk of heart disease.