Quick answer: Black cohosh is a North American plant whose root has been used for generations to support women through menopause, especially for hot flashes. Today it is one of the most studied botanicals for this stage of life. The research is genuinely mixed: some trials and a 2023 review point to a benefit for overall menopausal symptoms, while an earlier Cochrane review found no clear difference from placebo. It is generally well tolerated, with rare reports of liver problems that are worth knowing about.
Key takeaways
- Black cohosh (Actaea racemosa) is not estrogen and does not appear to act like estrogen in the body.
- The most common daily amount in studies is about 40 mg of root extract.
- Reviews disagree: a 2023 analysis of 22 studies was favorable, while a 2012 Cochrane review of 16 trials was not.
- Talk with your provider before using it, especially if you have liver concerns, take medication or have a hormone-sensitive condition.
What is black cohosh?
Black cohosh is a tall flowering plant in the buttercup family, native to the woodlands of eastern North America. Its botanical name is Actaea racemosa, and you may also see the older name Cimicifuga racemosa. The part used in supplements is the root and rhizome (the underground stem).
Indigenous peoples of North America used the root for a variety of purposes, and by the 1800s it was a familiar women's tonic in American herbal practice. In the 20th century, standardized black cohosh extracts became popular in Germany, where much of the early clinical research was done. Today it appears in many menopause support supplements, either alone or blended with other botanicals.
One important note: black cohosh is a different plant from blue cohosh. Blue cohosh has a different safety profile and should not be confused with black cohosh.
What does black cohosh do for menopause?
Women most often look to black cohosh for support with hot flashes and night sweats, along with related changes in sleep and mood during the menopause transition.* Most clinical studies have focused on these vasomotor symptoms and on overall menopause symptom scores.
Does black cohosh contain estrogen?
No. This is one of the most common questions, and the answer has changed over time. Early researchers assumed black cohosh worked like a plant estrogen. Later laboratory and human studies found no meaningful estrogen-like activity. Black cohosh does not appear to change estrogen levels, breast tissue or the uterine lining in the ways estrogen does.
Scientists now think black cohosh may act on the brain's signaling systems instead, including serotonin, dopamine and opioid receptors involved in temperature regulation, mood and sleep. That mechanism is still being studied and is not fully confirmed. It does, however, explain why black cohosh is often described as a non-hormonal botanical.
What does the evidence say?
Here is where honesty matters. The research on black cohosh is substantial, but it does not all point in the same direction.
Reviews that found a possible benefit
According to the U.S. National Center for Complementary and Integrative Health (NCCIH), a 2023 review of 22 studies found that black cohosh products were potentially beneficial for menopause symptoms overall. Hot flashes improved, but the review did not find clear benefits for anxiety or low mood.
Reviews that found no clear difference
An earlier Cochrane review, published in 2012, pooled 16 randomized trials with 2,027 women. The typical dose was 40 mg per day for an average of about 23 weeks. Compared with placebo, the authors found no significant difference in hot flush frequency or menopause symptom scores, and they concluded the evidence was insufficient to support its use. They also noted that the trials varied widely and that better studies were needed.
Why the results differ
Several factors help explain the mixed picture:
- Different products. Extracts vary in how they are made, standardized and dosed, so one study's product may not match another's.
- A strong placebo response. Hot flash studies are known for large placebo effects, which makes small differences hard to detect.
- Different women. Some trials enrolled women in early perimenopause, others well after menopause, and some included women with a history of breast cancer.
- Different combinations. Many products, and some studies, pair black cohosh with other botanicals.
Professional groups reflect this uncertainty. The Menopause Society's 2023 position statement on non-hormonal options did not recommend herbal supplements for hot flashes, citing insufficient evidence. Many women still choose botanical support as part of a broader routine, ideally with their provider's knowledge. That is a personal decision, and the clearest way to make it is with accurate information.
How much black cohosh is typical?
Most clinical studies have used about 20 to 40 mg of standardized root extract per day, and the Cochrane review found a median of 40 mg daily. Products vary, so always follow the label on the specific product you use. Many studies lasted three to six months, so effects in research were typically measured over weeks rather than days.
Is black cohosh safe?
According to NCCIH, black cohosh has generally been well tolerated in studies lasting up to 12 months. Mild side effects such as stomach upset or headache have been reported.
The main safety question involves the liver. A small number of people taking black cohosh products have developed liver problems, sometimes serious. These cases are rare, and it is not clear whether black cohosh itself was the cause. Contamination or misidentified plants may have played a role. Even so, it is sensible to:
- Tell your healthcare provider before starting, especially if you have a history of liver problems.
- Stop and contact your provider if you notice signs such as dark urine, yellowing of the skin or eyes, or unusual fatigue.
- Ask your provider first if you have a hormone-sensitive condition such as breast cancer, take medications, or are pregnant or breastfeeding.
- Choose products from established companies that list the exact amount of black cohosh extract per serving.
Black cohosh and red clover together
Black cohosh is often paired with red clover, a plant that naturally provides isoflavones. A 2021 meta-analysis in Nutrients found that red clover extracts were associated with modestly fewer hot flushes per day than placebo, while noting that more high-quality studies are needed. Because the two plants are thought to work through different pathways, some formulas combine them.
Immunotec She+ pairs 40 mg of black cohosh root extract with 40 mg of red clover extract, plus 100 mg of ginger extract for everyday digestive comfort and 60 mg of konjac glucomannan, in a single apple and blueberry jelly stick.* It contains no hormones, no added sugar and no artificial colors. For a full overview, read Navigating Menopause Naturally.
Who might consider black cohosh?
Black cohosh may interest women who want a non-hormonal botanical option to support comfort during the menopause transition, and who have talked with their provider about their health history. It is not a replacement for medical care. If hot flashes are severe or disrupting your life, your provider can discuss the full range of options, from lifestyle strategies to prescription treatments. Our guide to non-hormonal approaches to hot flashes walks through them, and what to ask your doctor about menopause supplements will help you prepare for that visit.
Frequently asked questions
What does black cohosh do for menopause?
Black cohosh is a botanical traditionally used to support women through menopause, especially for hot flashes and night sweats. Research results are mixed, with some reviews finding a possible benefit and others finding no clear difference from placebo.
Does black cohosh act like estrogen?
Current research suggests it does not. Black cohosh has not shown meaningful estrogen-like activity in human studies, and scientists think it may act on brain signaling systems involved in temperature, mood and sleep.
How much black cohosh is typically used?
Most studies used about 20 to 40 mg of standardized root extract per day. Always follow the label on the specific product you use.
Is black cohosh safe?
It has generally been well tolerated in studies lasting up to a year. Rare liver problems have been reported, so talk with your provider before starting and contact them if you notice dark urine, yellowing skin or unusual fatigue.
Is black cohosh the same as blue cohosh?
No. Blue cohosh is a different plant with a different safety profile and should not be confused with black cohosh.
References
- National Center for Complementary and Integrative Health. Black Cohosh.
- Leach MJ, Moore V. Black cohosh (Cimicifuga spp.) for menopausal symptoms. Cochrane Database Syst Rev. 2012;(9):CD007244. Summary
- The 2023 nonhormone therapy position statement of The North American Menopause Society. Menopause. 2023;30(6):573-590.
- Kanadys W, et al. Evaluation of clinical meaningfulness of red clover extract to relieve hot flushes and menopausal symptoms. Nutrients. 2021;13(4):1258.
*These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease. This article is for general education and is not medical advice. Talk with your healthcare provider before starting a supplement, especially if you are pregnant, nursing, take medication or have a medical condition.