Soy Isoflavone May Be Protective Against Osteoporosis in Post-Menopausal Women

Category: Women's Health

Since the published results of the Women's Health Initiative found that hormone replacement therapy (HRT) caused an increased risk in heart disease and cancer, women have been turning to natural hormone replacement. Soy is a known phytoestrogen, with weak estrogen activity that was implemented as an alternative for postmenopausal women.

Results taken from study showed that the intake of soy caused a positive effect on bone mineral density and provided protection against the development of osteoporosis. Various studies have found that soy protein supplementation increases bone mineral density (BMD) and reduces the rate of bone resorption. However, it was not fully understood if these results were due to the isoflavone (phytoestrogen) content or the increase in protein, since many of the studies showed an alteration of protein intake in women on soy protein who had positive effects on BMD.

A study published in the Journal of Women's Health investigated if soy isoflavone in an isolated form would have the same beneficial effects on bone resorption and BMD. Postmenopausal women took 110 mg of soy isoflavone per day for 6 months. The measured variables included markers of bone resorption, BMD in the lumbar spine and hip. The measurements were taken at baseline for both groups, as well as throughout the study. Dietary intake and physical activity were also assessed.

The study found that isolated soy isoflavone does decrease bone resorption in postmenopausal women. The reduction was significant in the treatment group when compared to baseline as when compared to placebo. The study also showed significant increase in BMD in the lumbar spine as compared to baseline and placebo.

The authors suggest that long-term studies are still needed to fully understand the effects of isolated soy isoflavones on both bone mineral density and bone resorption in postmenopausal women.

Posted by Kristopher Foster on November 26, 2008 10:00 AM