According to data from a new study published in a recent issue of Menopause, soy consumption is most beneficial when introduced before menopause. Women who consume soy-based diets premenopause and then switch to a typical Western diet postmenopause often suffer from similar atherosclerosis issues as lifelong consumers of the Western diet. Women who switch from a Western diet to a soy diet postmenopause may only benefit if there is no significant atherosclerosis prior to the switch.
The study, conducted at Wake Forest School of Medicine, explored four main diets consumed by nonhuman primates throughout pre and postmenopausal states: a continuous soy diet; a switch from an animal protein diet to a soy diet; a continuous animal protein diet; and a switch from soy to an animal protein diet. The nonhuman primates were randomly assigned to diet groups premenopause, and then studied for 34 months after menopause was induced.
The results showed that subjects with continuous soy consumption and those who switched to a soy diet showed reduced atherosclerosis compared to groups consuming animal protein postmenopause. Subjects switched to soy from animal protein had significantly reduced cholesterol levels. Neither of the two postmenopausal soy groups were significantly different in levels of plaque build-up, but the “lifelong” soy consumers had an overall lower proportion of complicated plaque in their arteries.
“Soy-rich diets contain isoflavones, estrogen-like compounds that have been postulated to be cardioprotective,” says Dr. Giselle Meléndez, M.D., instructor of cardiology at Wake Forest School of Medicine and the study’s lead author. “Their molecular structure technology resembles that of estrogen and may act through the same receptors in the body. The key here is beginning soy supplementation (about 25 g per day) before menopause and substitute the consumption of proteins derived from animal sources with soy-rich products.”
Learn more about Wake Forest School of Medicine’s study about soy-based diets.