Protocol
Ashwagandha standardized root extract 300 mg twice daily
Langade 2019 (PMID PubMed ID: the permanent number the US National Library of Medicine gives a published paper. Each one links to that paper's record on PubMed. 31728244): 300 mg twice daily for 10 weeks improved sleep onset latency, total sleep time and sleep quality against placebo An inactive substitute made to look like the real treatment, so participants cannot tell which one they received. in adults with insomnia and anxiety.
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How this letter has changedLatest: October 2026 · Corrected.
The B rests on Langade et al. (Cureus, 2019; PMID 31728244) and a five-trial meta-analysis A study that pools the numbers from several trials into one combined estimate. of randomized sleep trials (Cheah et al., PLoS One, 2021; PMID 34559859). Pooled randomized evidence is replication The same finding reproduced by a separate research group. A result seen once can be chance or bias; a replicated one is harder to explain away. under the written rule; what the pooling does not show is a second trial of the same extract at the same dose, which the record states and which is not what the flag means. Flag removed, letter unchanged. Applied the written grade definition under the editor's standing instruction of October 2026 (Arnold Sandlow, D.C.).PMID 31728244 PMID 34559859
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Ashwagandha is a plant root extract sold as a supplement. In adults with insomnia and anxiety, 300 mg twice a day for 10 weeks helped people fall asleep faster, sleep longer and sleep better than a dummy pill. A review of five studies found a small benefit for sleep. It was larger in people with insomnia and at 600 mg a day or more. All results were reported by the people themselves. Bedtime-only use was not tested, since the study gave it twice a day.
Langade 2019 (PMID 31728244): 300 mg twice daily for 10 weeks improved sleep onset latency, total sleep time and sleep quality against placebo in adults with insomnia and anxiety. A meta-analysis of five randomized trials (PMID 34559859) found a small but significant overall effect on sleep, more prominent in adults diagnosed with insomnia and at doses of 600 mg per day or above.
Why this gradeThe reasoning, and what the grade does not cover.
Grade B on self-reported sleep in adults with insomnia and anxiety. A randomized double-blind Neither the participants nor the people assessing them know who received the real treatment until the trial ends. trial at 300 mg twice daily for 10 weeks improved sleep onset latency, total sleep time and sleep quality against placebo (Langade et al., 2019; PMID 31728244), and a meta-analysis of five randomized trials found a small significant effect, larger in diagnosed insomnia and at 600 mg/day or more (Cheah et al., 2021; PMID 34559859).
WHY NOT Athe outcomes are self-reported.
WHAT THIS GRADE DOES NOT COVERstress or cortisol as an endpoint The outcome a trial measures to decide whether the treatment worked, such as heart attacks, blood pressure or a symptom score. for this letter (a separate trial measured cortisol; PMID 23439798), and bedtime-only dosing, since the trial gave the extract twice daily.
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The evidence, in fullThree papers, each linked to its PubMed record.
Langade et al. (Cureus, 2019; PMID 31728244): randomized double-blind placebo-controlled trial, 300 mg twice daily for 10 weeks. Confirmed by Cheah et al. (PLoS One, 2021; PMID 34559859): meta-analysis of five randomized trials, standardized mean difference -0.59 (95 percent CI -0.75 to -0.42). Serum cortisol was a measured outcome in a separate 60-day randomized trial of the same extract at the same dose (Chandrasekhar et al., Indian J Psychol Med, 2012; PMID 23439798). Grade B.
Serum cortisol at baseline and 8 weeks: a 60-day randomized placebo-controlled trial of the same extract at 300 mg twice daily (PMID 23439798) reported substantially reduced serum cortisol against placebo (P=0.0006). The Perceived Stress Scale (PSS-10) at baseline and 60 days as the primary subjective endpoint. For male hormone applications, track total testosterone at baseline and 8 weeks. A standardized full-spectrum root extract is what the cited trials used; other ashwagandha extracts differ in standardization.
Evidence notes: randomized trial, meta-analysis
Endpoint graded: Self-reported sleep in adults with insomnia and anxiety (self_report)
Last reviewed: July 2026
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