In nine cortisol studies, ashwagandha was taken daily for weeks
All nine studies in one cortisol review had people take ashwagandha daily, in studies lasting 30 to 112 days. None tested what one dose does.
What the study found
Nine cortisol studies tested ashwagandha over weeks of daily doses
Every one of nine cortisol studies in one review had people take ashwagandha daily, in studies lasting 30 to 112 days. In the seven that measured cortisol in the blood, it ended lower than where it started. The evidence describes weeks of daily use, and none of it tested a single dose.
The caveat · Results only at each course's end
The review gives each study's cortisol only at the end of its course, so how soon any fall begins is unknown. The falls it reports are measured against where people started, not against placebo, and one of the nine had no placebo group. The two studies that measured cortisol in saliva disagreed, and one found no change. Extract and dose differ from study to study, from 60 mg to 5 g a day.