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meta analysis1,002 participants

Ashwagandha and Cortisol Reduction: 2022 Meta-Analysis of 12 RCTs

DJP
Reviewed by , MD, Board Certified Internal Medicine

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TL;DR — Quick Answer

A 2022 meta-analysis of 12 RCTs (n=1,002) found that ashwagandha supplementation significantly reduced serum cortisol levels by a weighted mean of 11.3% compared to placebo (p < 0.001). Effects were strongest with KSM-66 extract at 600mg/day for 8+ weeks.

Key Findings

  • Ashwagandha supplementation reduced serum cortisol by 11.3% vs placebo (WMD = -2.74 ng/mL, 95% CI: -4.24 to -1.24)
  • Perceived stress scores (PSS) decreased significantly (SMD = -0.76, p < 0.001)
  • KSM-66 root extract showed the largest cortisol reduction among extract types studied
  • Dose-response analysis favored 600mg/day over lower doses for cortisol outcomes
  • Supplementation duration of 8 weeks or longer produced significantly greater effects than shorter interventions

Study Details

An investigation into the stress-relieving and pharmacological actions of an ashwagandha extract: A randomized, double-blind, placebo-controlled study
Lopresti AL, Smith SJ, Malvi H, Kodgule R — Medicine (2019)
Ashwagandha 240mg/day reduced morning cortisol by 23% after 60 days vs placebo
60 participantsHigh
Adaptogenic and Anxiolytic Effects of Ashwagandha Root Extract: A Double-Blind RCT
Salve J, Pate S, Debnath K, Langade D — Cureus (2019)
Serum cortisol reduced significantly at both 250mg and 600mg doses after 8 weeks
58 participantsHigh

Practical Takeaway

For adults experiencing chronic stress with elevated cortisol, 600mg of KSM-66 ashwagandha root extract daily for at least 8 weeks is a well-supported intervention. The cortisol reduction of ~11% is clinically meaningful and comparable to structured stress-management programs.

Summary

A systematic review and meta-analysis examining the effects of ashwagandha extract supplementation on serum cortisol levels and perceived stress across 12 randomized controlled trials involving 1,002 participants.

Related Supplements

Ashwagandha

References

  1. (). An investigation into the stress-relieving and pharmacological actions of an ashwagandha (Withania somnifera) extract. Medicine. DOI
  2. (). Adaptogenic and Anxiolytic Effects of Ashwagandha Root Extract in Healthy Adults. Cureus. DOI
  3. (). A prospective, randomized double-blind, placebo-controlled study of safety and efficacy of a high-concentration full-spectrum extract of ashwagandha root. Indian Journal of Psychological Medicine. DOI