Results from a double-blind, placebo-controlled German study suggest that black cohosh (Cimicifuga racemosa) benefits and is well tolerated by postmenopausal women (Menopause, 2006, vol. 13, no. 2).

Researchers treated 62 postmenopausal women either with black cohosh, conjugated estrogens, or placebo for 12 weeks. Evaluation of blood samples and vaginal smears determined that black cohosh may help prevent osteoporosis by stimulating the activity of osteoblasts, cells responsible for building bone. The herb also demonstrated weak estrogenlike effects in the vaginal mucosa, thereby alleviating the vaginal dryness commonly associated with menopause.

These positive results come on top of some bad press for black cohosh, a member of the buttercup family. In recent months, both Australia and the United Kingdom have issued labeling regulations warning of possible adverse liver reactions to black cohosh products.

However, researchers in the recent study, conducted at the University of Gottingen, found no evidence of increased liver enzymes (a liver damage indicator) in participants.

"Black cohosh has not been shown to cause liver damage," says Michael McGuffin, president of the American Herbal Products Association. "In fact, based on emerging information, we are requesting that our colleagues in other countries review the basis on which their decisions about black cohosh were made and reconsider their positions." As with any medicine, the AHPA advocates that anyone taking herbs talk with their doctor about dosage and any possible symptoms.