Effects of Ashwagandha (Withania Somnifera) on Stress and Anxiety: A Systematic Review and Meta-analysis

Abstract

BackgroundAshwagandha (Withania somnifera) is an adaptogenic herb used to prevent and treat psychosomatic disorders. This systematic review and meta-analysis evaluated the effects and safety of Ashwagandha on psychosomatic functions related to stress and anxiety among patients. MethodsA comprehensive search was conducted in MEDLINE, EMBASE, PubMed, PsychINFO, and the Cochrane Library for articles published from January 2000 to January 2022. Randomized controlled trials that examined the effects of Ashwagandha on stress and anxiety were included. Two authors independently extracted all relevant data from the included studies. Both subjective and objective measures of stress and anxiety were assessed as outcome variables. ResultNine randomized controlled trials involving 558 patients were eligible for this study. The findings of the meta-analysis showed a significant effect of Ashwagandha formulations on the Perceived Stress Scale (PSS) (MD = -4.72, 95% CI = [-8.45 to -0.99]), Hamilton Anxiety Scale (HAS) (MD = -2.19, 95% CI = [-3.83 to -0.55]), and serum cortisol levels (MD = -2.58, 95% CI = [-4.99 to -0.16]) compared to the placebo group. Among the included studies, four reported mild to moderate adverse events. ConclusionThe findings from the included studies indicate that Ashwagandha formulations have beneficial effects on stress and anxiety. The adverse effects associated with Ashwagandha are limited; however, further information is required to determine its safety with long-term administration.