Middle-aged women may find some relief from hot flushes and other menopause problems with soy supplements, according to Chinese researchers.
They found daily supplements of soy germ isoflavones reduced the sudden sweats more than inactive placebo pills after six months.
But a US expert wasn't convinced by the results, which run counter to other published studies.
"The majority of them are showing no benefit," said Dr William W. Wong, a nutrition researcher at Baylor College of Medicine in Houston who wasn't involved in the new work.
How the study was done
The new study, published online in Menopause, is based on 90 Chinese women. A third of them received placebo pills, while the rest took soy germ isoflavones, either 84 or 126 mg a day. They all kept diaries of their hot flushes and filled out questionnaires about various other symptoms of menopause.
At six months, their Kupperman scores – a measure of symptom severity that ranges from 0 to 63 – had dropped by more than 40% from an initial value of about 25 in the soy groups.
The number of hot flushes also fell from about 20 a week to less than 10.
While the same pattern was seen in the placebo group, it was less pronounced. Their symptom score dropped by 29% and the number of hot flushes by 35%, according to Dr Yan-bin Ye of Sun Yat-sen University in Guangzhou.
The work was supported by Frutarom Netherlands, which also donated the supplements.
Dr Wong cautioned that the new study was small and that the women involved only had few hot flushes. He said it was "hard to believe" that soy would have an effect on these women.
Exercise to relieve menopause symptoms
In one of his own studies, Dr Wong found no effect from soy germ isoflavones among women who took the supplements for two years.
The standard drug treatment for stubborn menopause symptoms is hormone replacement therapy, which carries the risk of serious side effects such as increased risk for heart attack, stroke and breast cancer.
"It is something they need to gauge, is it worth the risk?" Dr Wong told Reuters Health.
He generally recommends exercise and an active lifestyle to women who feel bothered by menopause.
Asian women think menopause problems are natural
Soy supplements also have side effects such as nausea, bloating, and constipation, according to the National Institutes of Health.
Dr Wong said that in Asia, women tend to think of menopause problems as a natural part of life – not a medical problem.
"There is a major cultural difference in how we deal with menopause symptoms," he added.
The new study didn't find significant hormone changes in women who took soy supplements, and Dr Wong said the compounds are probably safe for women.
"Consuming soy is not bad for them," Dr Wong noted, "but it might be a waste of money if you don't see any benefit."
(Frederik Joelving, Reuters Health, January 2012)
Soy may help in menopause