Study: Popular Menopause Remedies Have Very Low (or Dangerously High) Levels of the Critical Ingredient

Purchasing a packet of ‘menopause support’ tablets online doesn’t take more than a couple of minutes. One tablet daily should support ‘mental clarity’ and ‘hormonal balance’ and ‘decreasing discomfort’ from sweating and hot flushes. 

However, when Good Health investigated some of the most popular menopause supplements promoted on Google and Amazon (the products ranking highest in searches or appearing as the top ‘sponsored,’ paid-for ads), many were found not to contain what they claimed, with some possibly putting health at risk.

Supplements for menopause are big business and account for 95 percent of the global menopause market, valued at over $17 billion.

Women go through menopause, defined as a year after the final menstrual cycle, on average around age 51; however, menopause symptoms — including memory problems, insomnia, and hot flashes — can happen from around a decade prior, as their estrogen levels begin to fall.

In the UK, about 29 percent of the 13 million menopausal or perimenopausal women have tried supplements to manage symptoms instead of or in addition to prescription medicines like hormone replacement therapy, according to a British Nutrition Foundation survey in 2022.

Black cohosh — benefits and concerns

Black cohosh is a member of the buttercup family that is common in North America and one of the most popular. Also known scientifically as Cimicifuga racemose, it is used commonly to combat symptoms including sweats, joint aches, headaches, and sweats.

It is available in liquid and tablet forms and is included in many multi-ingredient menopause supplements. 

“Black cohosh is one of the few herbal remedies for which there is some evidence base for effectiveness, particularly for the management of vasomotor symptoms — sweats and flushes,” said Dr. Fionnuala Barton, a general practitioner in Hertfordshire, England, and a menopause specialist.

“It has been known for decades to be helpful in menopause, and there are some relatively high-level researcher studies that have shown it effective,” said Barton.

Scientists don’t know exactly how it works, but theories are that it regulates or boosts estrogen levels and other hormones.

In a 2012 review by Cochrane, 16 studies involving over 2,200 women were examined, and it was found the evidence was ‘inconclusive’ as to whether or not black cohosh was more effective than a placebo for managing symptoms of menopause. However, some individual studies have shown positive effects.

A randomized controlled trial involving 84 women with an average age of 51, published in 2013 in the Journal of Chinese Medicine, found those taking black cohosh for eight weeks experienced a noticeable improvement in 21 menopause symptoms, including lack of libido, anxiety, and hot flashes when compared with women taking the placebo.

Although there is ‘some evidence’ black cohosh can relieve sweats and hot flashes, it warns the quality of products may vary and ‘safety is uncertain.’

Almost 100 cases of severe side effects from taking black cohosh, including jaundice and liver damage, have been reported since 1998 to the UK’s medicines watchdog, the Medicines and Healthcare Products Regulatory Agency (MHRA).

However, the genuine number of side effects may be much higher as only one in ten adverse drug reactions is reported. Additional side effects include vomiting, dizziness, stomach problems, and headaches. It is unclear why black cohosh could trigger these.

In 2006, the MHRA declared all black cohosh supplements should carry package warnings and in-patient information leaflets about the risk to liver health. 

It is unclear why the herb could cause liver damage, but scientists suspect problems are more likely when women take unregulated supplements. Because it has a ‘medicinal’ effect, the MHRA says supplements containing black cohosh in the UK should be tested to adhere to strict safety and quality standards.

Some companies are flouting the rules

However, some UK and United States companies are flouting the rules by selling unlicensed black cohosh online as ‘food supplements’ and continuing to promote them with sponsored listings on Google or Amazon. 

Although marketed supplements are supposed to comply with British regulations, there is little regulators can do to block overseas manufacturers from selling sub-pars products to customers.

“Enforcing rules on online sales is a difficult, often impossible ‘task,’” according to Edzard Ernst, professor emeritus at Exeter University and researcher specializing in the study of complementary medicine.

In an investigation by into black cohosh supplements being marketed to women and whether they met safety standards and contained what they claimed on the package, 20 packages were purchased.

These included supplements bought from retailers and several promoted in sponsored and ‘Shopping’ results on Google.

Samples were sent to a Swiss laboratory and tested to identify if they contained chemical markers unique to black cohosh. Results showed that while nine supplements contained the herb, 11 either didn’t have black cohosh or the levels were so low they were undetectable with a standard test.

Those supplements were tested further using two separate tests: one to determine if they contained a combination of five chemical markers unique to black cohosh and another highly sensitive one used to test the quantity of herb in each tablet.

The test revealed a sample of the tablets made by U.S.-based PipingRock contained 242 mg of black cohosh. This amount is almost six times higher than approved levels. 

Tests on three Amazon supplements found none contained what the label claimed they had.

Instead, they were weaker, with one appearing to contain an unapproved, undeclared plant species.

Colin Wright, a professor of pharmacognosy studying drugs from natural sources at Bradford University, says manufacturers may substitute black cohosh for less expensive species grown in China.

Although there is no evidence that was the case in the four brands tested, Wright added, “adverse effects are more common with products that aren’t licensed herbal medicines; substitution may explain some of this.”

“It seems that black cohosh products which are not good quality are likely to be less effective or not to be effective, and they may be more likely to give toxic effects such as those we have seen reported to the MHRA,” continued Wright. 

He pointed to cases where other unregulated herbal products have caused harm, including several cases where slimming remedies caused patients to develop kidney failure.

“There’s no doubt that sometimes quite serious effects can be caused when herbal medicine preparations are of poor quality,” Wright added.

Professor of pharmacognosy and ethnopharmacology at University College London, Michael Heinrich, believes regulations around the sale of black cohosh should be tightened to ensure they can’t only be sold as medicines.

“Food supplements simply need to contain what is on the label — but often not even this is the case. Black cohosh is known to have positive therapeutic effects, but may also have some side-effects, so in my view, it must be (treated as) a medicine,” explained Heinrich.

Dr. Barton agrees that there should be more protection for consumers, “In the menopause space particularly, there are companies trying to sell products to women who are in a vulnerable position and who want to believe something will make them feel better,” she said.