Active constituents
Black cohosh contains several ingredients, including triterpene glycosides (e.g., acetin
and 27-deoxyactein) and isoflavones (e.g., formononetin). Other constituents include aromatic
acids, tannins, resins, fatty acids, starches, and sugars. As a woman approaches menopause, the signals between the ovaries and pituitary gland
diminish, slowing down estrogen production and increasing luteinizing hormone (LH) secretions.
Hot flashes can result from these hormonal changes. Earlier animal studies4
5 and a human clinical trial6 suggested that black cohosh had some estrogen activity in the body and also decreased LH secretions.
However, more recent animal studies7 and a clinical trial8 have found no
estrogen activity for black cohosh extracts. Further clinical trials are needed to determine
whether black cohosh has significant estrogenic actions in the body.
Small German clinical trials support the usefulness of black cohosh for women with hot
flashes associated with menopause.9 10 A review of eight clinical trials
found black cohosh to be both safe and effective for symptomatic relief of menopausal hot
flashes.11 Other symptoms which improved included night sweats, insomnia, nervousness, and irritability. A clinical trial
compared the effects of 40 mg versus 130 mg of black cohosh in menopausal women with
complaints of hot flashes.12 While hot flashes were reduced equally at both
amounts, there was no evidence of any estrogenic effect in any of the women. Although further
trials are needed, this trial suggests that black cohosh is best reserved only for the
symptomatic treatment of hot flashes associated with menopause and is not thought to be a
substitute for hormone replacement therapy in menopausal and postmenopausal women.
A recent study suggests black cohosh may protect animals from osteoporosis.13 Human studies have not confirmed
this action.
References
1. Leung AY, Foster S. Encyclopedia of Common Natural Ingredients
Used in Food, Drugs, and Cosmetics, 2d ed. New York: John Wiley & Sons, 1996,
88–9.
2. Castleman M. The Healing Herbs. Emmaus, PA: Rodale Press,
1991, 75–8.
3. Foster S. Herbs for Your Health. Loveland, CO: Interweave
Press, 1996, 12–3.
4. Jarry H, Harnischfeger G, Düker E. Studies on endocrine effects
of the contents of Cimicifuga racemosa. 2. In vitro binding of compounds to estrogen
receptors. Planta Medica 1985;51:316–9.
5. Jarry H, Harnischfeger G. Studies on endocrine effects of the contents
of Cimicifuga racemosa. 1. Influence on the serum concentration of pituitary hormones
in ovariectomized rats. Planta Medica 1985;51:46–9.
6. Düker EM, Kopanski L, Jarry H, Wuttke W. Effects of extracts from
Cimicifuga racemosa on gonadotropin release in menopausal women and ovariectomized
rats. Planta Medica 1991;57:420–4.
7. Einer-Jensen N, Zhao J, Andersen KP, Kristoffersen K.
Cimicifuga and Melbrosia lack estrogenic effects in mice and rats.
Maturitas 1996;25:149–53.
8. Liske E, Wüstenberg P, Boblitz N. Human pharmacological
investigations during treatment of climacteric complaints with Cimicifuga racemosa
(Remifemin®): No estrogen-like effects [Poster presentation]. 2nd International Congress
on Phytomedicine, London, October 15–16, 1998.
9. Stoll W. Phytopharmaceutical influences atrophic vaginal epithelium.
Double-blind study on Cimicifuga versus an estrogen preparation.
Therapeutikon 1987;1:23–32.
10. Warnecke G. Using phyto-treatment to influence menopause symptoms.
Med Welt 1985;36:871–4.
11. Düker EM, Kopanski L, Jarry H, Wuttke W. Effects of extracts
from Cimicifuga racemosa on gonadotropin release in menopausal women and
ovariectomized rats. Planta Medica 1991;57:420–4.
12. Liske E, Wüstenberg P. Therapy of climacteric complaints with
Cimicifuga racemosa: a herbal medicine with clinically proven evidence [Abstract
#98.0020]. Poster Presentation, 9th Annual Meeting of the North American Menopause Society,
Toronto, Canada, September 16–9, 1998.
13. Kadota S, Li JX, Litt Y, et al. Effects of cimicifugae rhizome on
serum calcium and phosphate levels in low calcium dietary rats and on bone mineral density in
ovariectomized rats. Phytomed 1996/7;3:379–85.
14. Murray MT. The Healing Power of Herbs. Rocklin, CA: Prima
Publishing, 1995, 376.
15. Bradley PR, ed. British Herbal Compendium, vol 1.
Bournemouth, Dorset, UK: British Herbal Medicine Association, 1992, 34–6.
16. Blumenthal M, Busse WR, Goldberg A, et al. (eds). The Complete
Commission E Monographs: Therapeutic Guide to Herbal Medicines. Boston, MA: Integrative
Medicine Communications, 1998, 90.
17. Gruenwald J. Standardized black cohosh (Cimicifuga) extract
clinical monograph. Quart Rev Nat Med 1998;Summer:117–25.
Contradictory, insufficient, or preliminary
studies suggesting a health benefit or minimal health benefit.
