Health Benefits of Black Cohosh

Health Benefits of Black Cohosh

The Black Cohosh, Actaea racemose, grows wild in shady wooded areas of eastern North America and parts of Canada. It’s a member of the buttercup family and is also known as black snakeroot, bugbane, and squawroot.

The roots and rhizomes contain several substances that may be beneficial for health, including phytoestrogens, sugar compounds called glycosides, and iso-ferulic acids which have an anti-inflammatory effect.

It’s been used by indigenous tribes, settlers and, more recently, as a supplement. So what exactly makes it so special, and what can it do for you?

Chemical Makeup

One characteristic that makes black cohosh a unique and sought-after plant are the phytoestrogens within it. These, as the name might suggest, reproduce effects in the body similar to those of oestrogen. For health, they can be useful to alleviate some of the effects brought on by the menopause or PMS, such as hot flushes. This is one particular effect of the plant that will be explored in this article.

Black cohosh also has an effect on the brain. Its phytoestrogenic properties mean that it works on receptors in the brain that transmit serotonin, the “happiness” chemical in the brain. Serotonin can help with pain relief, sleep and mood swings, so anything that can help its reception in the brain will have a knock-on effect in these areas.

Menopause Treatment

During menopause, the balance of oestrogen and progesterone becomes unbalanced. It is thought that the aforementioned phytoestrogenic chemicals within black cohosh bind to oestrogen receptors in the body and increase their activity. This helps to balance hormones and relieve uncomfortable symptoms such as hot flushes, irritability, mood swings and sleep disturbances.

Black cohosh has been well studied for its effect on menopausal symptoms, but the findings are somewhat contradictory. Several studies have shown great improvement, while for others the benefits have been modest. This may mean that you have to take black cohosh for longer than most supplements to experience any benefit.

In one large-scale study, 704 menopausal women took black cohosh over a four week period. 87% of the participants experienced improved physical and psychological symptoms. Of these, 49% experienced complete relief of symptoms, while 38% reported significant improvements. In a separate study menopausal women who took black cohosh over a 12 week period found their average number of hot flushes fell from 5 per day to less than 1.

There are many who believe that black cohosh has little effect on menopausal effects as a whole, aside from hot flushes. A 2008 study found that it had no effect on things such as vaginal epithelium (the tissue found on the outside of the vagina) or endometrium (the uterine lining), both of which can cause issues during the menopause. One reason for the varying results may be that many studies do not note the kind of preparation they use, which makes repeating results or finding correlations more difficult. It also means it’s more difficult to garner the quality of the supplement used in trials.

Anti-inflammatory and Antioxidative Effects

In the past, black cohosh has been used to treat inflammation, along with its myriad of other uses. Now, there’s some scientific evidence to show that it can be effective in this area: a study from the University of Hong Kong has identified a compound within black cohosh and similar species of plant that plays a role in its anti-inflammatory role. It’s because of this that black cohosh is often combined with other anti-inflammatory herbs such as willow bark, sarsaparilla, and guaiacum to treat inflammation associated with osteoarthritis and rheumatoid arthritis.

It’s been discovered that it has an antioxidant effect too, protecting cells against damage done on a molecular level. This is important, as the oxidative stress this damage can cause affects delicate parts of the body such as the brain, even leading to certain cancers and strokes in serious cases. A 2002 study showed that black cohosh can “protect against cellular DNA damage” that is associated with oxidative stress. Incredibly one antioxidative compound in black cohosh was also found to inhibit the growth of certain breast cancer cells. It should be noted that this was a very specific extract, and that further research is required into the subject.

Effects on the Brain

As mentioned previously, black cohosh can assist with serotonin receptors on the brain. One piece of research from the Journal of Agriculture and Food Chemistry suggests this may be the source of its influence on hot flushes. Ultimately, the link between serotonin and hot flushes requires more research as well, but there have been some interesting results found in the area.

One study gave participants with hot flushes a selective serotonin reuptake inhibitor (SSRI), which increases the amount of serotonin in the brain. They found that those using the SSRI had a higher satisfaction rate with the drug in fighting their hot flushes compared to a placebo (70% to 43% respectively).

This means if there is a link between black cohosh and increased serotonin uptake then its positive news for menopausal symptoms.


Black cohosh can be taken in several different forms, most commonly as tea, supplements, or tinctures. For the treatment of menopausal symptoms, it appears to be effective in daily dosages between 20mg to 80mg and often takes a minimum of two weeks for the beneficial effects to be seen. The North American Menopause Society also recommends “lifestyle changes” alongside the use of black cohosh supplements for relief of menopausal symptoms.

Black cohosh can be used to induce labour and so should not be taken during pregnancy. It should also be avoided during lactation due to insufficient data supporting its safety.

It is not yet clear whether black cohosh is safe for women with hormone-sensitive conditions such as endometriosis, fibroids, breast cancer or ovarian cancer. Therefore it should be avoided. If you are concerned, speak to your GP.

Side Effects

Black cohosh has a low incidence of adverse reactions and is considered safe when taken in the recommended dosages. However, for some, it can cause mild side effects including stomach upset, cramping, headache, rash or vaginal spotting. If any side effects persist or worsen you should discontinue use and consult your GP.

Doctors and researchers are unsure about the long term side effects of black cohosh. Some say that it may be responsible for liver damage when taken for an extended period of time. Experts are wary, urging caution when using black cohosh for longer than six months. Also ensure that you are sticking to the directions given on the supplement packaging and not overdosing. If you experience jaundice (skin and eyes turning yellow), darker urine than usual or chronic fatigue then cease supplementing and visit your doctor.

Black cohosh contains salicylates and so should be avoided by those who are allergic to aspirin. It may also interact with certain prescription medications, so you should consult your GP prior to supplementation.


With all the research that’s been conducted on the plant, black cohosh has proven to be beneficial to human health while still retaining some mystery. Nonetheless, for those who are looking for a gentler way to tackle menopausal symptoms, its phytoestrogenic effects may provide relief, especially from uncomfortable hot flushes. Its other effects may give those taking it a boost in other areas too, but for the most part this is for those struggling with hormonal changes later in life.