Newsflash: hot flashes and soy…more on genistein

Posted by on Dec 17, 2010 in hot flash | 0 comments

There’s some exciting news on the soy isoflavones front: for the first time, researchers have shown that a synthetic formulation of genistein, a plant-based estrogen component of soy, may actually reduce both the frequency and severity of hot flashes. Genistein is an interesting isoflavone, in that studies have linked it to some truly potentially important benefits, including preventing or reducing heart disease risk and attenuating bone loss in menopausal women. While the verdict is still out on its role in these conditions, it does appear to influence hot flashes and only in the best way possible! Moreover, this is the first time that a synthetic formulation has shown to have some degree of benefit in this regard.

Granted, this is a small study of only 84 menopausal women, 40 of whom took synthetic genistein for 12 weeks and 40 who took a sugar placebo tablet. The results? By the study’s end, women taking 1, 30-mg capsule daily reduced the number of hot flashes by half (51%, from about 10 per day to 5 per day) and also experienced significant declines in how long they lasted. The synthetic formulation, which was standardized, was also shown to be safe and did not detrimentallly impact the lining of the uterus. Notably, however, the researchers did note that there are not enough data to recommend isoflavones to women who’ve had breast cancer or at high risk for developing, even though current data suggest that exposure does not adversely affect breast tissue density or cancer cell proliferation, meaning that it is likely that with more study, they will ultimately prove safe for use in breast cancer patients.

Your key take-away is that there may be a viable option for women who are flashing but want to stay away from hormones. However, this is what we still need to know:

  • Will genistein work on larger groups of menopausal women?
  • Is formulation important?
  • Is the 30 mg dose the lowest dose that will confer these sort of benefits?
  • Are there any other factors that these women had in common that might be influencing outcomes?

As with any novel data like these, it’s great to be cautiously enthusiastic. Stay tuned!

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