This Health Alert is intended for readers interested in learning about the prevention, diagnosis, and management of osteoporosis.
The risk of developing osteoporosis increases as we grow older. Exercise, proper nutrition, and – when appropriate – medication can all help to prevent osteoporosis. But what about isoflavones? A reader asks: My sister-in-law has been eating isoflavone-enriched cereal bars to reduce her risk of osteoporosis. Do they really work? Here’s what the science suggests.
Many women use natural alternatives to hormone replacement therapy, such as soy supplements, in an attempt to reduce their risk of osteoporosis with fewer side effects. And some evidence suggests that isoflavones, which are estrogen-like plant chemicals found in soybeans, may protect against postmenopausal bone loss. But based on currently available data, it does not appear that isoflavone-enriched foods can help reduce the risk of osteoporosis.
In fact, European researchers used the most rigorous type of evaluation -- a double-blind placebo- controlled trial -- to test the potential effect of isoflavones on women's bones. They randomly assigned 300 healthy, white, early-postmenopausal women (average age 53) to eat cereal bars and biscuits enriched with 110 mg of isoflavones daily for one year or to eat the same food without isoflavones.
The results of the study, which were reported in the American Journal of Clinical Nutrition, were thumbs down for the isoflavone-enhanced foods. Eating them did not improve bone mineral density of the lumbar spine or total body and did not affect the natural turnover of bone.
The bottom line: There's no harm in eating those soy-enriched cereal bars, but there's no solid evidence they will reduce the risk of osteoporosis.
