The herbal supplement black cohosh, taken for relief of menopausal hot flashes, doesn't work any better than a placebo, a study finds.
Previous research had brought mixed results. Nevertheless, sales of black cohosh have soared as women have turned away from estrogen-replacement therapy, which has been linked with an increased risk of stroke (SN: 4/15/06, p. 228: Available to subscribers at Estrogen Safety: Studies raise cancer, blood clot questions).
Epidemiologist Katherine M. Newton of the Group Health Center for Health Studies in Seattle and her colleagues recruited 351 women who responded to a mailed questionnaire seeking trial volunteers. The women, between the ages of 45 and 55, were each experiencing an average of seven hot flashes, including night sweats, per day.
The scientists randomly divided the volunteers into groups to receive one of five treatments: estrogen therapy, black cohosh, black cohosh and other supplements, the co