What are safe dosages of Black cohosh?

Black Cohosh is available in 40mg capsules,recommended dose 2 times daily. I have been taking 280mg (7capsulesx40mg) and noticed an improvement in the amount of hotflashes I have during the day. I didn't realize that I was exceeding the recommended dosage until I googled today. I recently found Black Cohosh 550mg by Herbal Select and was wondering about the high dosage. It seems to be the only one above 40 mg on store shelves. I have purchased it but I'm nervous to take it. Should I be concerned about this high dosage?


Photo of Lorene Sauro
Herbel select is a whole herb product - in other words they whole leaf or root has been ground up and put in the capsule. The 40 mg product you have been taking is a stadardized extract, where they have take the chemical they feel is responsible for the action and standarized it to a 40 mg strength of that chemical. There are those who feel this is the way to go with an herb in order to confirm the consistent potency. But the history of herbs has been with whole herbs and there are preliminary indications that there are issues with standardized extracts. It is like taking the vitamin C out of the food as opposed to eating the food which has many other beneficials items in it beyond vitamin C. It also implys man is smarter than nautre, which we know has proven false so many time before. That being said if you have been taking 7 x 40 mg and found a benefit - then it appears the version you are taking is fine for you. It is hard to say if you would need more of the whole herb as you have needed with your current brand. There are other chemicals and nutrients present in the whole herb so it may work better for you or it may not. Only one way to find out but do not be mislead by the 550 mg number - it may have the same amount of the active ingredient used in your currrent brand of 40 mg- it just also has a lot of other elements including vitamins and minerals.

You may want to try adrenal support for your hot flashes as they are a result of overworked and probably tired adrenals. Ask for an adrenal adaptogen at your local health food store.

Response by Lorene Sauro B.A., R.H.N
Photo of Guy Chamberland
According to Health Canada, an adult can take between 40 mg and 2400 mg of the dried root and rhizome of Black cohosh (Actaea racemosa). When selecting a product you need to verify the amount of Dried Herb Equivalent (DHE) of Black cohosh root and/or rhizome. Many products are made from extracts of Black cohosh and not powdered dried root and/or rhizome. Some of these extracts may be a 4 to 1 (extract ratio 4:1) or 8 to 1 (extract ratio 8:1) extract of the dried root and rhizome. A 4:1 extract is a powder that is 4 times more concentrated than the dried root and rhizome or in the case of an 8:1 extract it would be 8 times more concentrated. Therefore, 50 mg of a 4:1 extract is equivalent to 200 mg of the dried root and rhizome. Some companies may express the latter as 200 mg of the DHE.
Product labels should contain the information required for you to determine the amount of dried root and/or rhizome (i.e., DHE) that each capsule or tablet contains. Some manufacturers may write it very clearly stating the product contains 50 mg of an extract equivalent to 200 mg of the dried root and rhizome of Black cohosh. Others may write 50 mg of a 4:1 extract of the dried root and rhizome. Always look for the amount of an herb, or herb part like the root and/or rhizome, expressed as the DHE. Safety data is usually expressed based on the DHE since extracts vary from company to company.
In the case of a product that is made from the powdered dried root/rhizome, the label would read, for example, 550 mg of Black cohosh dried root. You can safely take 4 capsules per day of the 550 mg Black cohosh dried root product. Taking 4 capsules provides a daily dose of 2200 mg of Black cohosh dried root and this is below the maximal daily intake recommended by Health Canada of 2400 mg.
Response by Guy Chamberland M.Sc., Ph.D.


Before starting any new health program or before you begin taking any medication, natural medicine, or supplement, always check with your primary health care provider.

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