Soy Isoflavones Effective in Addressing Hot Flashes

TOKYOWomen seeking relief from menopausal hot flashes would do well to try isoflavone supplements, if those products are extracted from soy or synthesized to contain identical isoflavone profiles to soy, according to a new meta-analysis (Menopause. ePub 19 Mar 2012. DOI: 10.1097/gme.0b013e3182410159). The study, coordinated out of Tokyo's National Institute of Health and Nutrition's Center for International Collaboration and Partnership by Kyoko Taku, Ph.D., M.D., was the largest review to date seeking to assess the efficacy of soy isoflavones in alleviating hot flashes in perimenopausal or postmenopausal women.

Researchers searched for double blind, randomized controlled trials evaluating the effects of isoflavones on the frequency, severity, or composite score (frequency x severity) of hot flashes compared with placebo. A total of 19 trials were included in the systematic review, from 277 potentially relevant publications identified, and 17 trials were selected for meta-analysis on the effect of isoflavones on hot flash frequency (13 trials) and severity (9 trials). The meta-analysis revealed ingestion of soy isoflavones (median, 54 mg; aglycone equivalents) for six weeks to 12 months significantly reduced (by 20.6 percent) the frequency of hot flashes compared with placebo; similarly hot flash severity was reduced by 26.2 percent compared with placebo. Isoflavone supplements providing more than 18.8 mg of genistein (the median for all studies) were more than twice as potent at reducing hot flash severity than supplements with lower genistein levels.

The key finding in this study is that when you limit the analysis to isoflavone supplements derived from soy or those with profiles identical to soy, there is a very consistent effect on hot flash relief," stated Mindy S. Kurzer, Ph.D, professor of nutrition at the University of Minnesota, hormone expert and contributing author to the study, in a statement released by Archer Daniels Midland Co. (ADM), the supplier of NovaSoy soy isoflavones. Almost all studies in the meta-analysis show a consistent reduction in hot flash frequency and severity."

Steve OBrien, product manager of Natural Health and Nutrition at ADM, commented, We are pleased that such a thorough evaluation of the most well-conducted studies showed that soy isoflavones are highly effective for the alleviation of hot flashes. To maximize relief, ADMs NovaSoy brand soy isoflavones reflect the same profile of isoflavones naturally present in soy, including higher amounts of genistein."

More information on nutritional ingredients for women's health, including addressing menopausal symptoms, can be found in the Natural Products INSIDER Women's Health Content Library .