Black cohosh is an herbal remedy often recommended for the treatment of hot flashes. A common symptom of menopause, hot flashes are thought to result from changes in estrogen levels. While some proponents claim that black cohosh can act as a phytoestrogen, studies testing black cohosh's effects on hot flashes have yielded mixed results so far.
The Science Behind Black Cohosh and Hot Flashes
For a 2010 report published in Alternative Therapies in Health and Medicine, researchers analyzed nine clinical trials on the use of black cohosh for the treatment of menopausal symptoms (including hot flashes). Results revealed that herbal formulas containing black cohosh improved overall menopausal symptoms by 26 percent. However, in a research review published in Drugs & Aging the previous year, scientists sized up 16 studies on black cohosh and menopausal symptoms and deemed their results inconclusive (largely due to flaws in study design).
There is also limited support for the theory that black cohosh can cool hot flashes among postmenopausal women undergoing or finished with breast cancer treatment. In a 2006 study published in the Journal of Clinical Oncology, for instance, researchers found that taking black cohosh for four weeks failed to reduce hot flashes among breast cancer patients. While participants given a placebo reported a 27 percent decrease in hot flashes, those treated with black cohosh reported only a 20 percent decrease in hot flashes.
The safety of long-term use of black cohosh is uncertain, according to the National Center for Complementary and Alternative Medicine (NCCAM). In fact, the NCCAM warns that there have been several reports of hepatitis and liver failure among women who were taking black cohosh. In addition, black cohosh may cause a number of minor side effects (such as stomach pain, headache, and rash).
Using Black Cohosh for Hot Flashes
For help in soothing hot flashes, the National Institutes of Health (NIH) recommends avoiding caffeine, alcohol, and spicy foods; eating soy foods; exercising regularly; and practicing slow, deep breathing whenever you feel a hot flash coming on. Receiving acupuncture or taking up tai chi, yoga, or meditation may also help ease menopausal symptoms, according to the NIH.
If you're considering the use of black cohosh in treatment of hot flashes (or any other condition), make sure to talk to your primary care provider before starting your supplement regimen.
National Center for Complementary and Alternative Medicine. "Black Cohosh [NCCAM Herbs at a Glance]". NCCAM Publication No. D268. July 2005.
National Institutes of Health. "Menopause: MedlinePlus Medical Encyclopedia". January 2011.
Shams T, Setia MS, Hemmings R, McCusker J, Sewitch M, Ciampi A. "Efficacy of black cohosh-containing preparations on menopausal symptoms: a meta-analysis." Altern Ther Health Med. 2010 Jan-Feb;16(1):36-44.
Palacio C, Masri G, Mooradian AD. "Black cohosh for the management of menopausal symptoms : a systematic review of clinical trials." Drugs Aging. 2009;26(1):23-36. doi: 10.2165/0002512-200926010-00002.
Pockaj BA, Gallagher JG, Loprinzi CL, Stella PJ, Barton DL, Sloan JA, Lavasseur BI, Rao RM, Fitch TR, Rowland KM, Novotny PJ, Flynn PJ, Richelson E, Fauq AH. "Phase III double-blind, randomized, placebo-controlled crossover trial of black cohosh in the management of hot flashes: NCCTG Trial N01CC1." J Clin Oncol. 2006 Jun 20;24(18):2836-41.
Borrelli F, Ernst E. "Black cohosh (Cimicifuga racemosa) for menopausal symptoms: a systematic review of its efficacy." Pharmacol Res. 2008 Jul;58(1):8-14.