This summary table contains detailed information about research studies. Summary tables offer an informative look at the science behind many breast cancer guidelines and recommendations. However, they should be viewed with some caution. In order to read and interpret research tables successfully, it is important to understand some key concepts. Learn how to read a research table.
Introduction: Taking black cohosh (an herb) has been suggested as a way to relieve menopausal symptoms. However, most randomized controlled trials do not show a benefit for breast cancer survivors or cancer-free women.
Although studies have not shown any harmful side effects of black cohosh for breast cancer survivors, there are no long-term safety data.
Learn more about black cohosh.
Learn about the strengths and weaknesses of different types of studies.
Study selection criteria: Randomized controlled trials with at least 80 participants and meta-analyses.
Table note: Relative risk above 1 indicates increased risk. Relative risk below 1 indicates decreased risk.
Study Population(number of participants)
Menopausal Symptoms Studied
Black Cohosh Reduced Menopausal Symptoms More Than Placebo?
Randomized controlled trials
Herbal Alternatives for Menopause Study [1-2]
Osmers et al. 
Hot flashes and sleep problems
Uebelhack et al. *
294 cancer-free women
Pockaj et al. 
132breast cancer survivors and women at high risk
Frei-Kleiner et al. 
van der Sluijs et al. †
93 cancer-free women
Jacobson et al. 
85breast cancer survivors
Cochrane Collaboration 
* Supplement contained black cohosh and St. John's wort. † Supplement contained black cohosh and Chinese herbs.
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