What Soy Could Do for Older Women

Soy protein with isoflavones may help protect menopausal women from osteoporosis, bone weakening


If you're looking for a natural way to reduce your osteoporosis risk, you may want to give soybeans a try.

A new study from the UK found that a diet rich in soy protein with added isoflavones may effectively safeguard against bone weakening and osteoporosis in menopausal women. Isoflavones are chemicals found in soybean foods that are similar to the female sex hormone estrogen.

"We found that soy protein and isoflavones are a safe and effective option for improving bone health in women during early menopause," said lead study author Thozhukat Sathyapalan, MD, FRCP, academic head of endocrinology at the University of Hull in England, in a press release. "The actions of soy appear to mimic that of conventional osteoporosis drugs."

Osteoporosis is a condition which causes the bones to become weak and brittle — so brittle, in fact, that even a fall or mild stress can cause a fracture. Osteoporosis-related fractures most often occur in the hip, wrist or spine.

While osteoporosis can affect men and women of all ages, older women who are past menopause are especially at risk. Bone loss can occur quickly in the years immediately after menopause because less estrogen, which protects against bone loss, is being produced.

For this study, Dr. Sathyapalan and team gave 200 women in early menopause either a daily supplement containing soy protein with 66 milligrams of isoflavones or a daily supplement containing soy protein alone.

According to Dr. Sathyapalan, 66 mg of isoflavones is equal to the amount often seen in soy-rich Asian diets. By comparison, the average Western diet typically contains only between 2 and 16 mg.

Over the course of six months, these researchers looked for changes in the women's bones by measuring blood levels of the proteins βCTX and P1NP. Low levels of these proteins are linked to a lower risk of osteoporosis.

The women on the soy diet with isoflavones were found to have significantly lower levels of βCTX in their blood than the women on soy alone. The women on soy with isoflavones were also found to have a lower risk of cardiovascular disease.

Dr. Sathyapalan said his team plans to next examine whether diets rich in soy with isoflavones have benefits beyond bone health.

This study was presented Nov. 1 at the Society for Endocrinology's annual conference in Edinburgh, UK. Research presented at conferences may not have been peer-reviewed.

Information on funding sources and conflicts of interest was not available at the time of publication.