Does Ashwagandha supplementation have a beneficial effect on the management of anxiety and stress? A systematic review and meta‐analysis of randomized controlled trials

Abstract

Clinical trial studies revealed conflicting results on the effect of Ashwagandha extract on anxiety and stress. Therefore, we aimed to evaluate the effect of Ashwagandha supplementation on anxiety as well as stress. A systematic search was performed in PubMed/Medline, Scopus, and Google Scholar from inception until December 2021.We included randomized clinical trials (RCTs) that investigate the effect of Ashwagandha extract on anxiety and stress. The overall effect size was pooled by randomeffects model and the standardized mean difference (SMD) and 95% confidence interval (CIs) for outcomes were applied. Overall, 12 eligible papers with a total sample size of 1,002 participants and age range between 25 and 48 years were included in the current systematic review and meta-analysis. We found that Ashwagandha supplementation significantly reduced anxiety (SMD: À1.55, 95% CI: À2.37, À0.74; p = .005; I 2 = 93.8%) and stress level (SMD: À1.75; 95% CI: À2.29, À1.22; p = .005; I 2 = 83.1%) compared to the placebo. Additionally, the non-linear dose-response analysis indicated a favorable effect of Ashwagandha supplementation on anxiety until 12,000 mg/d and stress at dose of 300-600 mg/d. Finally, we identified that the certainty of the evidence was low for both outcomes. The current systematic review and dose-response meta-analysis of RCTs revealed a beneficial effect in both stress and anxiety following Ashwagandha supplementation. However, further highquality studies are needed to firmly establish the clinical efficacy of the plant.

Effect of Broad-Spectrum Hemp Extract on Neurobehavioral Activity on the Immobilization Stress-Induced Model in Sprague Dawley Rats

“…Ashwagandha (tradename KSM-66) was chosen as the positive control because it is the most popular dietary supplement to manage stress. In addition, it has been the subject of published research showing that it can attenuate stress [ 17 , 18 ].…”

Adaptogens on Depression-Related Outcomes: A Systematic Integrative Review and Rationale of Synergism with Physical Activity

“…In spite of the meta-analytic evidence supporting its use, we did not include Crocus sativus L. (saffron) in this practical recommendation due to its high cost which reduces accessibility [ 135 ]. Furthermore, it is worth noting the potential impact of Withania somnifera (Ashwagandha) supplementation since it has been recently concluded in systematic reviews with meta-analysis to be an effective strategy to improve physical function [ 136 ] and to relieve stress and anxiety [ 137 ] in different populations.…”

A comprehensive review on the hepatotoxicity of herbs used in the Indian (Ayush) systems of alternative medicine

“…[29] Even though Ashwagandha is claimed to have health benefits and therapeutic effects (increasing longevity in the elderly, improving immune status, antianxiety, improving recovery from fatigue, increasing memory, and reproductive function), there is a lack of validated clinical evidence from well-designed and rigorously performed studies that conclusively prove its safety or efficacy. [30] Flavonoids, phytosteroids, coagulins, alkaloids such as cuscohygrine and anahygrine, and steroidal lactone triterpenoids, also known as withanolides, are among the bioactive substances found in Ashwagandha. There are unsubstantiated claims that the terpenoid withaferin-A has hepatoprotective qualities.…”

“…[29] Even though Ashwagandha is claimed to have health benefits and therapeutic effects (increasing longevity in the elderly, improving immune status, antianxiety, improving recovery from fatigue, increasing memory, and reproductive function), there is a lack of validated clinical evidence from well-designed and rigorously performed studies that conclusively prove its safety or efficacy. [30]…”