Black Cohosh
Black cohosh is the most studied herb with some possible efficacy in decreasing hot flashes, even when used alone (Cheema 2007, Bai 2007), but not necessarily other health parameters such as cholesterol or blood sugar.
Typical dose: 40 milligrams one to two times a day
Brand names: Remifemin is the most studied brand, but Estroven is a combination product that comes in both AM and PM formulations and has some evidence of efficacy as well
Safety: Unlikely to be estrogenic in nature, so safer in women with a history of estrogen-related cancers (Walji 2007). Theoretical concern of hepatotoxicity although most products have been found to be free of adulteration.
Research evidence: Findings are mixed; some trials have shown little benefit. A 2012 Cochrane review (Leach 2012) showed no evidence and that has been backed up by more recent RCT’s. A counter analysis of the Cochran review showed using different studies there is a positive effect although small in size in the decreasing of hot flashes (Beer 2013). The most recent meta-analysis in JAMA did not find any evidence of an association between black cohosh and hot flash symptoms (Franco 2016).
Most common side effects: Headache, GI upset, rash
Note: Not to be confused with blue cohosh, which has a different indication and can have more significant and severe side effects