By Dr. Mercola
Fever, pneumonia, menstrual issues and even musculoskeletal pain – these are just some health problems that Native Americans believe the black cohosh plant may be good for.1 After discovering it over two centuries ago,2 these civilizations are still relying on this perennial plant to address certain illnesses. But how exactly does black cohosh work, and can it really offer benefits for your health?
What Is Black Cohosh?
A member of the buttercup plant family, black cohosh (Actaea racemose – it was previously known as Cimicifuga racemosa3) is a flowering perennial plant that grows in certain parts of the U.S. and Canada.4 From June to September, the plant produces white flowers, but take a look at its roots, and you’ll see that they’re black. This is where the plant gets its name. The rootstock and roots are also knotty and rough, which is why the plant is called “cohosh” – this is actually a Native American word for “rough.”5
The black cohosh plant thrives best in moist and rich soil, and can be seen growing on hillsides and in open woods. It can grow up to 8 feet tall, with pinnate leaves and irregular tooth leaflets.6 The root is believed to be the most beneficial part of the plant. Black cohosh root has a long history of being used medicinally.7 Its rhizomes, which also grows underground, may have healing uses, too.8
Black cohosh is known by other names as well, such as black snakeroot, baneberry, bugwort, rattlesnake root, squaw root and Sheng Ma, to name a few.9 However, remember that black cohosh and blue cohosh should not be confused with each other, as they’re very different plants.10 Blue cohosh (Caulophyllum thalictroides) has been historically used to induce labor or miscarriage, but eventually it was found to be dangerous for the fetus.11
Black Cohosh Uses for Women’s Health
Aside from Native Americans, Europeans have also been using black cohosh for over four decades now. Specifically in Germany, it’s actually approved for alleviating pain associated with premenstrual syndrome, dysmenorrhea and menopause.12 In fact, black cohosh achieved its popularity because of claims stating that it can help control menopause symptoms, including:13,14
Sleep issues and night sweats
Decreased sex drive
Ringing in the ears
Bone density loss (among postmenopausal women)
Reduced mental performance (among postmenopausal women)
This is mainly due to the estrogen-like response in black cohosh, which helps increase low levels of estrogen that are prevalent in most menopausal women. It’s even said that black cohosh may work as a natural hormone replacement.15
Do the Studies Support Black Cohosh’s Purported Claims?
Black cohosh’s potential for easing menopause symptoms has been known since the 1950s, and individual studies are said to support these claims,16 such as:
• A review published in 2010 found that menopausal women had a 26 percent reduction in hot flashes and night sweats when using black cohosh supplements.17
• Published in the journal Gynecological Endocrinology in 2013, a review found that women who took black cohosh had, on average, more reduced menopausal symptoms compared to women who were given a placebo.18
• A 2017 study published in the Neuroscience journal found that black cohosh potentially helped regulate the body temperature of female rats that had no ovaries.19
However, please note that currently there’s still no final and conclusive scientific evidence of black cohosh’s effectiveness for this condition. In addition, most studies that show the positive benefits did not exceed six months to one year of use, which is why long-term use of this supplement is never recommended.20 Therefore, as much as possible, exercise extreme caution before supplementing with black cohosh.
Other Potential Health Benefits Linked to Black Cohosh
In addition to its potential for alleviating menopause symptoms, black cohosh is also believed to help ease other conditions. In fact, Native Americans used it to treat fever, musculoskeletal pain, pneumonia, cough, and even aid in sluggish labor.21 Other possible benefits linked to black cohosh include:22
• Preventing digestive issues: Black cohosh may help improve nutrient uptake, assist in removing waste products, and even reduce constipation and risk of gastric ulcers.
• Easing sleep problems: It’s said to be a natural sedative that can help ease stress, anxiety and insomnia.
• Alleviating premenstrual symptoms: This herb is said to help muscles to relax, easing tension that may lead to painful cramps. It may be useful for women who have irregular cycles as well.23
Again, there’s no conclusive evidence confirming these potential effects of black cohosh, so make sure to consult a physician prior to using this herbal supplement.
Black Cohosh Dosage: What’s the Typical Amount for Supplementation?
Black cohosh supplements are available in different forms, such as capsules or liquid extracts. The roots are also dried and transformed into tea. In some cases, the herb is used as an ingredient in herbal mixtures. You can buy it in drug or health stores, or through online sellers.24
There’s no set dose for this supplement, although in studies, 20 to 40 milligram tablets, taken twice a day, are typically used to ease menopausal symptoms. Do not take over 900 milligrams of black cohosh a day, and do not take it for long periods of time.25 This supplement is ill-advised for children and teenagers. There are also groups of people who should not take black cohosh at any costs, such as:
• People who are allergic to aspirin
• People who have liver disease, seizure disorders or have a high risk of blood clots and stroke
• Pregnant and breastfeeding women
• Women with uterine or breast cancer
• Women suffering from endometriosis
Furthermore, while black cohosh may have positive effects for hot flashes during menopause, please note that women who experience hot flashes as a side effect of cancer therapy (such as chemotherapy or radiation) and cancer medications like tamoxifen (Nolvadex), should not take this herbal supplement.
Not only can this herb interfere with cancer drugs, but there are also concerns stating that its plant-based estrogens (phytoestrogens) may actually stimulate breast tumor growths.26
Black Cohosh May Have Unpleasant Side Effects as Well
The side effects linked to black cohosh usually occur when high doses of this supplement are ingested. Headaches and upset stomach are two common examples. In some people, more severe complications like liver injury have also occurred.
Thus, if you’re using any medication that affects the liver, consult your healthcare provider prior to using black cohosh. People who use hormone replacement therapy, sedatives, birth control pills and blood pressure medicine should also refrain from using this supplement without their physician’s approval.27
Remember: Use Black Cohosh as a Last Resort
While black cohosh may offer potential for easing menopausal symptoms and other hormone-related conditions, I do not recommend it as your first go-to option. Instead, try addressing your diet and see if this may have positive effects on your symptoms. Other strategies include optimizing your vitamin D levels and getting sufficient levels of high-quality omega-3 fats.
Frequently Asked Questions About Black Cohosh
Q: How long does it take for black cohosh to work?
A: According to scientific evidence, black cohosh may help relieve hot flashes and other menopause symptoms after about a month of treatment.28 However, keep in mind that there are no studies confirming its effects after long-term use, so refrain from taking it for long periods of time.
Q: Is black cohosh safe?
A: While black cohosh may be generally safe for healthy people, there are certain individuals who are advised not take this supplement. It can also come with unpleasant side effects like stomach upset and headaches. If you experience these, stop taking it immediately.