Can Black Cohosh Actually Help Menopause Symptoms? - Chatelaine

The plant has been touted for its ability to improve hot flashes and night sweats. We asked two experts whether it really works.

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Perimenopause and menopause symptoms are far-ranging, but all have the ability to cause anything from discomfort to debilitating pain. So it's no wonder that people going through these life phases are always on the lookout for relief.

While menopause hormone therapy (MHT) is the gold standard for symptoms like hot flashes and genitourinary syndrome of menopause, not all menopausal people can use it—breast cancer patients and survivors, for example, shouldn't take MHT because of the risk of breast cancer recurrence. In search of other ways of treating symptoms, some people are turning to supplements with natural ingredients like black cohosh. But does black cohosh really work, and is it worth trying?

What is black cohosh?

Black cohosh is a tall, flowering plant indigenous to the eastern part of North America that comes from the same family as the buttercup. Found in the shady woodlands in this part of the continent, it's also sometimes called black snakeroot, bugbane or bugwort. The plant is used in dietary supplements and comes in capsules, tablets, tinctures, extracts and teas.

What does it purport to do?

Black cohosh was traditionally used by Indigenous communities in North America to treat a number of ailments including musculoskeletal pain, fever, cough, pneumonia and irregular periods. Today, black cohosh is most commonly used in supplements that help treat vasomotor symptoms of menopause (a.k.a. hot flashes and night sweats).

Does it really work?

There's just no evidence that black cohosh improves menopause symptoms, says Dr. Taryl Felhaber, a clinical instructor at UBC's Department of Family Practice and a Menopause Society certified menopause practitioner. "It's one of those things that claims it can make magical things. But there is no magic in menopause."

According to Felhaber, studies of black cohosh's effectiveness against menopause symptoms like hot flashes are "not definitive. They don't show significant improvements in any of the symptoms that they've studied so far," she says.

Related: Here's Why You Experience Hot Flashes During Menopause—And How To Treat Them

There have been several randomized controlled trials (the gold standard in medicine) looking into black cohosh and its effects on menopausal symptoms.

One of the first, published in 2006, found that there was no difference in the number and intensity of vasomotor symptoms between the group taking black cohosh and the control group (who took placebos) at three and six months. At 12 months, however, those taking the herbal supplements had significantly worse symptoms.

Another study, published in 2009, had similar outcomes, with the group taking black cohosh experiencing worse symptoms at six and nine months than those taking a placebo.

In 2012, the Cochrane Review (a systematic review of randomized controlled trials that aims to synthesize evidence from research around the world) evaluated 16 randomized controlled trials looking at black cohosh's effectiveness at reducing menopausal symptoms and found that there was "insufficient evidence" from these trials—they couldn't support the use of the herb for menopausal symptoms. (The review does say that black cohosh should be studied further to determine its usefulness.)

Finally, in its 2023 position statement on non-hormonal therapy for menopause symptoms, the Menopause Sociey recommends against using black cohosh due to the fact there's "no demonstrated evidence of benefit."

But what about the people who swear black cohosh has provided some relief? Felhaber says this is most likely a placebo effect—believing that a treatment is working even if it isn't. She adds that for hot flashes in particular, the placebo effect is especially common; up to 50 to 60 percent of those experiencing hot flashes will say, at first, that a placebo is working.

Are there any negative side effects to using black cohosh?

There are a few common side effects caused by black cohosh such as upset stomach, cramps, headaches, rash, a feeling of heaviness, spotting or vaginal bleeding and weight gain. There have also been some cases of liver damage linked to commercial black cohosh products.

Is it safe to use for menopause symptoms?

Not only is the research into black cohosh's ability to treat menopause symptoms inconclusive, but many black cohosh supplements on the market in Canada actually don't contain the correct species of plant.

Instead, plants like cimicifuga, another member of the buttercup family, are often used in black cohosh supplements. "But there's no trial to show that [that ingredient] actually has a positive effect on symptoms," Felhaber says.

A major problem with all supplements sold in Canada—not just black cohosh—is that they are not well regulated. There's not as much oversight as there is with pharmaceuticals, Felhaber says, and as a result, supplement ingredient lists are often found to be inaccurate. This means it's hard to know exactly how much black cohosh you're getting in each capsule (if the product is indeed black cohosh). "So, you could be getting many times what is considered a treatment dose," warns Felhaber. "Or you could be getting nothing."

Read more: Everything You Need To Know About Menopause