Soy isoflavones ineffective to prevent menopausal bone lost and symptoms

January 01, 0001

Soy isoflavones ineffective to prevent menopausal bone lost and symptoms

The goal of this study by US authors was to determine the efficacy of soy isoflavone tablets in preventing bone loss and menopausal symptoms. The study design was a single-center, randomized, placebo- controlled, double-blind clinical trial conducted from July 2004 through March 2009. Women aged 45 to 60 years within 5 years of menopause and with a bone mineral density T score of -2.0 or higher in the lumbar spine or total hip were randomly assigned, in equal proportions, to receive daily soy isoflavone tablets, 200 mg, or placebo. The primary outcome was changes in bone mineral density in the lumbar spine, total hip, and femoral neck at the 2-year follow- up. Secondary outcomes included changes in menopausal symptoms, vaginal cytologic characteristics, N -telopeptide of type I bone collagen, lipids, and thyroid function.

They found: "After 2 years, no significant differences were found between the participants receiving soy tablets (n = 122) and those receiving placebo (n = 126) regarding changes in bone mineral density in the spine (-2.0% and -2.3%, respectively), the total hip (-1.2% and -1.4%, respectively), or the femoral neck (-2.2% and -2.1%, respectively). A significantly larger proportion of participants in the soy group experienced hot flashes and constipation compared with the control group. No significant differences were found between groups in other outcomes."

The authors concluded: "In this population, the daily administration of tablets containing 200 mg of soy isoflavones for 2 years did not prevent bone loss or menopausal symptoms."

Soy isoflavone supplementation is a waste of money.

For the full abstract, click here.

Arch Intern Med 171(15):1363-1369, 8/22 August 2011 © 2011 to the American Medical Association
Soy Isoflavones in the Prevention of Menopausal Bone Loss and Menopausal Symptoms-A Randomized, Double-blind Trial. Silvina Levis, Nancy Strickman-Stein, Parvin Ganjei-Azar, Ping Xu, Daniel R. Doerge, Jeffrey Krischer. Correspondence to Dr. Levis: [email protected]

Category: T. Endocrine/Metabolic/Nutritional, M. Musculoskeletal. Keywords: soy, isoflavones, menopause, bone mineral density, menopausal symptoms, randomized controlled trial, journal watch.
Synopsis edited by Dr Linda French, Toledo, Ohio. Posted on Global Family Doctor 16 August 2011

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