Throughout the second half of the 20th century, American women and their physicians relied on estrogen replacement therapy to deal with the hot flashes, mood changes, vaginal dryness and other symptoms related to menopause. However, when adverse health outcomes forced the termination of the hormonal therapy arms of the Women's Health Initiative in 2004, women questioned the validity of the decades-long practice of hormone replacement therapy, or HRT. Many of them, seeking a safe way to relieve their menopausal symptoms, turned to herbal therapies, such as black cohosh.
Phytoestrogens
Phytoestrogens are plant-based isoflavonoids that mimic the effects of estrogens in your body. Phytoestrogens have been identified in several hundred plants, but the quality of these compounds and their effectiveness in humans vary widely, according to Dr. Duane Townsend, author of "A Maverick of Medicine Speaks to Women." Townsend cites soybeans, red clover and kudzu as the richest sources of "superior" isoflavones.
Black Cohosh
In her book, "Prescription for Herbal Healing," nutritional consultant Phyllis Balch states that black cohosh is useful for balancing hormone levels in both men and women due to its content of potent phytoestrogens. Balch reports that over 10 million units of Remifemin, a black cohosh preparation, are sold monthly in the United States, Australia and Europe. The makers of Remifemin claim the product leads to a 70 percent reduction in menopausal symptoms. However, Townsend labels black cohosh a "phytoestrogen impostor" with limited physiologic benefits.
Research
A 2011 review in "Frontiers in Bioscience" reports that black cohosh, like phytoestrogens, is moderately effective for relieving hot flashes, but it is not a phytoestrogen and its mechanism of action is unknown. A well-designed study performed at the Mayo Clinic and published in the June 2006 "Journal of Clinical Oncology" showed no benefit from black cohosh for treating hot flashes. In fact, women in this study preferred a placebo over the black cohosh preparation.
Considerations
Scientific studies evaluating black cohosh for the management of menopausal symptoms have produced conflicting results. Many of the studies showing benefit were performed nearly 30 years ago. Black cohosh appears to be safe, and its use accounts for a significant proportion of over-the-counter sales of alternative remedies for menopausal symptoms. Ask your doctor if black cohosh is appropriate for you.
References
- Australasian Menopause Society: 2004 March 3: Women's Health Initiative Oestrogen-Only vs. Placebo Study Terminated
- "A Maverick of Medicine Speaks to Women"; Duane Townsend, M.D., and Rita Elkins, M.H.; 2003
- "Prescription for Herbal Healing"; Phyllis A. Balch, CNC; 2002
- Remifemin: Menopause Relief
- "Frontiers in Bioscience"; Phytotherapy as Alternative to Hormone Replacement Therapy; M.D. Molla, et al.; January 2011
- "Journal of Clinical Oncology"; Phase III Double-Blind, Randomized, Placebo-Controlled Crossover Trial of Black Cohosh in the Management of Hot Flashes: NCCTG Trial N01CC; B.A. Pockaj, et al.; June 2006
