More soy more often better for hot flashes

Increased dose and frequency brings relief in UMMS study

By Sandra Gray

UMass Medical School Communications

May 24, 2013

Soy’s effect on hot flashes has earned mixed reviews, but a new study from UMass Medical School found that increasing the dose of soy supplements—and taking them throughout the day instead of just once—resulted in measurable relief from hot flash symptoms for some women. The findings suggest that women seeking alternatives to synthetic hormone therapy for relief of menopausal vasomotor symptoms, i.e., hot flashes, should consider isoflavone, the active component in soy supplementation.

“This study was prompted by the National Institutes of Health’s Women’s Health Initiative, which concluded that, while highly effective for symptom relief, hormone therapy has risks that may outweigh its benefits for many women,” noted lead author Sybil Crawford, PhD, who conducts research in women’s health with a focus on menopause. “Our study is of interest to women who don’t want to take hormones and their doctors.”

Published in the journal Menopause and reported on by Reuters Health, the study found that hot flash intensity scores were lowest in women who took the highest total daily dose, and in women with the highest dosing frequency of two or three times daily, with greater benefits on nighttime scores than on daytime scores.

“It makes sense that spreading the dose across the day versus taking it all in the morning was better for night sweats,” said Dr. Crawford, professor of medicine, noting that women complain more about night sweats than daytime hot flashes.

Further research to refine the understanding of hot flashes is under way at UMMS.

“We are looking at blood serum levels as well as self-reported dietary intake of isoflavines to get more precise data,” said Crawford. “We are also looking at the duration, intensity and characteristics of hot flashes to better understand their physiology, in hopes of targeting treatments and the women who will benefit most from them.”

Related links on UMassMedNow:

Times quotes Julia Johnson on risk of new hot flash drugs

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