Currently, there’s no surefire way to ease the symptoms of menopause: the hot flashes, night sweats and vaginal dryness that herald the end of a reproductive era. Hormone replacement therapy once seemed like a good idea for many women, until the medical treatment was linked to an increased risk of breast cancer and cardiovascular disease.
That’s one reason why, despite a lack of conclusive evidence, 40-50% of women in Western countries use complementary and plant-based therapies to help ease the symptoms of menopause. Now, a new review published in JAMA shows that some of these therapies may actually help.
Researchers from Erasmus University Medical Center in the Netherlands and the University of Cambridge in the U.K. analyzed a ream of randomized clinical trials—62 in all—that involved a total of 6,653 women. The studies looked at how certain plant-based therapies, including eating soy-rich foods, taking soy supplements, using herbal remedies and Chinese medicinal herbs, affected symptoms of menopause. (The analysis was funded by the supplement company Metagenics Inc.; the authors say it had no role in the design of the study or how it was conducted.)
Approaches using phytoestrogens—chemical compounds in plants that exert a similar action to the female sex hormone estrogen—were linked to a modest drop in daily hot flashes and vaginal dryness. These include whole-food sources of soy, soy extracts and red clover herbal supplements. The benefits didn’t extend to night sweats.
The researchers didn’t find any beneficial effect of Chinese medicinal herbs or black cohosh.
During menopause the sex hormone estrogen declines, which may be the reason why therapies using phytoestrogens appear to be effective against menopausal symptoms. Phytoestrogens connect with the receptors of estrogen, and therefore exert similar functions throughout the body, says the study’s leading scientist Dr. Taulant Muka, postdoctoral researcher at Erasmus University Medical Center.
Plant-based foods made from soybeans, like tofu, miso, tempeh and edamame, are rich in these soy isoflavones. “But when it comes to Western countries, the dietary intake of isoflavones is very small, around 2 mg per day,” Muka says, while women in Asian countries eat 25-50 mg per day. “What we found is most of the studies that have looked at isoflavones and menopausal symptoms had a dosage of 10-100 mg per day.”
More research is needed, especially the kind with a longer follow-up. Many of the studies kept track of women only for about 12-16 weeks, Muka says, and "we don’t know the long-term efficacy and safety.” Before adding these supplements, Muka recommends that women speak with their doctor and report any other medications they’re taking, since plant-based therapies used in combination with other treatments may have adverse effects.
“A healthy lifestyle is the backbone for easing menopausal symptoms and keeping you healthy in the long run,” Muka says.