Women who are worried about using estrogen for menopausal symptoms are resorting to various alternative therapies. What popular treatment has recently been shown to be ineffective? Black cohosh. This plant native to North America has traditionally been used to treat menopausal symptoms with mostly anecdotal evidence for efficacy. Dr. Katherine Newton of the Group Health Cooperative in Seattle decided to put black cohosh to a scientific test and enlisted 351 menopausal women between the ages of 45-55 who experienced at least two hot flashes a night. The women were randomly assigned to one of five treatment groups: 160 milligrams of black cohosh daily; a multi-botanical supplement containing 200 milligrams black cohosh and 9 other herbal ingredients including alfalfa, pomegranate and Siberian ginseng; a multi-botanical supplement plus increased soy consumption; hormone therapy; or placebo capsules. After 3, 6, and 12 months, black cohosh was no better than placebo in reducing the frequency or severity of hot flashes or night sweats. The same was true for the other herbal products.
Women who were given hormone therapy had significantly fewer hot flashes and night sweats than women given placebo. Another issue with black cohosh is its potential to interfere with the effectiveness of drugs used in cancer therapy. And then there is the problem that women relying on black cohosh may not be getting what they think they are getting. When researchers analyzed 11 of the most popular black cohosh tablets and capsules available in New York City using a process called high-performance liquid chromatography, they identified hundreds of different compounds within each black cohosh sample. Three of the products didn't have black cohosh at all, but instead contained an Asian species of Actaea, a Chinese herb related to black cohosh but without any proven effects in easing menopausal symptoms. Supplement manufacturers substitute Actaea for black cohosh, because it is less expensive to produce. What about women who are happy with black cohosh? Any concern here? There is in the UK where health authorities want a warning label on black cohosh products because of the possibility of liver damage. This problem isn’t particularly well documented but certainly any physician finding liver dysfunction should ask the patient about the use of black cohosh, or indeed, of any herbal remedy.