Black Cohosh

A native American plant long used to treat "female complaints," black cohosh (Cimicifuga racemosa) is one of the best-selling herbs for menopausal symptoms. It is found in various products including Remifemin. Available as pills, tinctures, and teas.

Claims, purported benefits: Relieves menopausal symptoms such as hot flashes, headaches, and insomnia, as well as menstrual cramps; safer than hormone replacement therapy.

Evidence: Some studies have found that black cohosh reduces hot flashes, sweating, headaches, and other menopausal symptoms. But in a well-designed clinical trial in 2006, the herb was no better than a placebo (and less effective than hormone therapy) in relieving hot flashes and sweating. Some researchers think black cohosh contains plant estrogens and thus has hormonal effects, but the latest reports have found no estrogens or hormonal effects.

Bottom line: Though black cohosh has been much studied, evidence is still thin. If you decide to try it, tell your physician. The British equivalent of the FDA recently warned that it can cause liver damage and ruled that products must carry a warning. Black cohosh might also interact with some medications (including some for hypertension) and cause stomach upset, headache, dizziness, and weight gain. It's unknown whether it has any effect, positive or negative, on breast cancer risk or whether women on birth control pills or hormone therapy can safely take it. Women who are pregnant or breast feeding should avoid it. In recent testing, several supplements did not contain the right herb or contained widely varying amounts. For some women with severe menopausal symptoms, short-term hormone replacement therapy (HRT) may be a better remedy than black cohosh—and at least you know what you’re getting; talk to your doctor.