Does ashwagandha help with stress?

Probably, for some people, in the short term. Several small randomised trials suggest that standardised ashwagandha root extracts can lower self-reported stress and anxiety over six to eight weeks. The trials are short, the products differ and rare liver reactions have been reported, so it is best used with a doctor's knowledge.

Choose Detailed for the fuller picture, or Scientific for mechanisms and study data.

Ashwagandha (Withania somnifera) has been used in Ayurveda for centuries as a rasayana, a herb for strength and steadiness. In the past fifteen years it has also been studied in modern clinical trials.

What the trials show

In a 2012 trial of 64 adults with chronic stress, people taking 300 mg of a root extract twice a day for 60 days reported larger improvements on stress and anxiety questionnaires than people taking a placebo, and their cortisol levels fell further. A 2022 meta-analysis that pooled randomised trials reached a similar conclusion: on average, ashwagandha reduced anxiety and stress scores compared with placebo.

How confident can we be?

Moderately. Most trials were small, lasted only a few weeks and tested specific commercial extracts, often with industry involvement. That is a reasonable starting point, but not the level of evidence we expect for a medicine.

Safety

Ashwagandha is usually well tolerated in trials. However, case reports describe liver injury, usually within two to twelve weeks of starting. It is not advised in pregnancy, and people with thyroid conditions, autoimmune disease or liver disease, or who take sedatives, should speak to a doctor first.

The proposed mechanisms centre on the hypothalamic-pituitary-adrenal axis. Withanolides, the steroidal lactones considered the principal actives, have been shown in preclinical models to modulate GABA-ergic signalling and stress-induced corticosterone release.

Clinical data: Chandrasekhar et al. (2012) randomised 64 adults to a full-spectrum root extract 300 mg twice daily or placebo for 60 days, reporting reductions in Perceived Stress Scale scores and serum cortisol. Akhgarjand et al. (2022) pooled randomised trials in a meta-analysis and found reductions in anxiety and stress scores, while noting sensitivity of the anxiety result to individual trials.

Heterogeneity is the main limitation: extracts vary in withanolide content, plant part (root versus leaf) and dose (typically 240 to 600 mg daily). Few trials exceed 12 weeks.

Safety: Björnsson et al. (2020) described five cases of cholestatic or mixed liver injury with latency of 2 to 12 weeks, all resolving without liver failure. Several European authorities have reviewed ashwagandha safety, and Denmark has restricted it in food supplements.