Ashwagandha vs holy basil (tulsi) for stress: what the trials show

A 2022 meta-analysis pooled 12 randomized trials with 1,002 adults aged 25 to 48. Ashwagandha lowered stress and anxiety scores compared with placebo, and the dose-response analysis favored 300 to 600 mg a day for stress. The trials varied a great deal, and the authors rated the certainty of the evidence low for both outcomes Akhgarjand 2022.

A 2025 meta-analysis narrowed in on two measures. Across seven trials, cortisol, a stress hormone, fell significantly; across six trials (488 participants in all), Perceived Stress Scale scores did not change significantly Albalawi 2025. So the hormone moved more clearly than how people said they felt.

For sleep, five randomized trials with 400 adults showed a small but significant improvement, larger in people diagnosed with insomnia, at 600 mg a day or more, and over eight weeks or longerCheah 2021. NCCIH says some ashwagandha preparations may be effective for insomnia and stress, and that the evidence on anxiety is unclear NCCIH.

Holy basil (Ocimum tenuiflorum, also called tulsi) is a different plant from the sweet basil used in cooking. In the best trial, 100 adults aged 18 to 65 who reported stress took 125 mg of a standardized extract twice a day, or placebo, for eight weeks. The extract group improved more on the Perceived Stress Scale and an insomnia questionnaire, had lower hair cortisol at week 8, and showed smaller cortisol and blood pressure responses to a lab stress test. The authors said gold-standard objective sleep measures are needed to confirm the sleep result, and the trial was funded by the extract's supplier Lopresti 2022.

An older six-week trial of 150 adults on 1,200 mg a day of a different extract found lower total stress-symptom scores than placebo Saxena 2012. A 2017 systematic review found 24 human studies of tulsi, all reporting favorable outcomes and none reporting significant adverse events, but most were smallJamshidi 2017. Results from one branded extract do not carry over to another, or to tulsi tea.

No trial has tested the two against each other. Ashwagandha's grade is higher because there are more trials from more groups, pooled in more than one meta-analysis, with a consistent direction on stress scores. Holy basil's evidence points the same way but rests on a couple of trials of specific products.

Neither is a substitute for dealing with the cause of stress, or for care when stress turns into lasting anxiety, low mood or trouble functioning. The stress page covers the non-supplement basics and when to see a clinician. If poor sleep is the main problem, see chamomile vs valerian for sleep and the sleep page.

Liver injury is rare but real. A case series from Iceland and the US Drug-Induced Liver Injury Network described five people who developed jaundice, itching, nausea and tiredness 2 to 12 weeks after starting ashwagandha supplements. None developed liver failure, and liver tests returned to normal within 1 to 5 months in the four who were followed up Bjornsson 2020.

Holy basil has fewer recorded problems: the extract trials reported it was well toleratedLopresti 2022; Saxena 2012, though they were short. In a small trial in people with type 2 diabetes, holy basil leaves lowered fasting blood glucose by 21.0 mg/dL compared with placebo leavesAgrawal 1996, so tell your clinician if you take diabetes medicine. We found no reliable human safety data for holy basil supplements in pregnancy.

Tulsi tea is the easy, low-dose way to try holy basil. Online, iHerb tulsi tea and iHerb ashwagandha list single-ingredient products; check the dose per capsule against the amounts above.