Supplement evidence
Ashwagandha
The anxiety and stress trials, and the liver-injury reports.
What Its Legal Status Actually Means
Read this before anything below it. Legal to sell is not the same fact as reviewed, verified, or approved.
Ashwagandha is sold in the US as a dietary supplement under the Dietary Supplement Health and Education Act of 1994 (DSHEA). That means the FDA does not review it for safety or effectiveness before sale, does not verify that a bottle contains the amount or the extract named on the label, and has never approved it to prevent, treat, or cure any condition — including stress, anxiety, or depression. Manufacturers may only make non-disease "structure/function" claims. The branded extracts that dominate the research literature (KSM-66 from Ixoreal Biomed, Sensoril from Natreon, Shoden from Arjuna Natural) are proprietary preparations that differ in root-versus-leaf source, withanolide concentration, and dose, so trial results for one product do not automatically transfer to another bottle on the shelf.
Quoted whole from the 2026-08-18 study harvest. Not summarized, not shortened.
What the Research Shows
5 records from the 2026-08-18 harvest, each checked against PubMed and Europe PMC on that date. How a study was designed, how many people were in it, and who paid for it are printed above what it found, because those three facts decide how much the finding is worth.
Study 1 · 2022
- Meta-analysis of randomized trials
- Reputable journal
- Independently funded
strong80/100Well-supported by good-quality research.
Read this first: The credible interval runs from -9.70 to -0.17, meaning the true effect could be near zero; the ashwagandha estimate rests on a handful of small trials, most of which were supplied or funded by extract manufacturers. The analysis was conducted at the Beijing Research Institute of Chinese Medicine, an institution with an institutional interest in herbal medicine generally, though its funding came from the university and Chinese national science programmes rather than from any supplement company.
A Bayesian network meta-analysis of 29 randomized trials covering 12 medicinal herbs in adults with diagnosed or subthreshold anxiety found Withania somnifera reduced Hamilton Anxiety Scale scores by 4.90 points (95% credible interval -9.70 to -0.17) — an estimate whose lower bound almost touches zero, drawn from trials the authors explicitly flagged as "limited by their small sample sizes." The authors' overall verdict was that all these results "should be considered preliminary because of the unconvincing sample sizes, together with the potential effectiveness of placebos."
How this record was checked
PubMed record 35378276 fetched via NCBI efetch 2026-08-18; title, authors, journal, year, DOI, the 29-trial count, and the Withania somnifera estimate (MD -4.90, 95% CrI -9.70 to -0.17) confirmed verbatim from the abstract. Europe PMC core record fetched 2026-08-18 lists funders "Beijing University of Chinese Medicine" and "National Major Science and Technology Projects of China" and no commercial sponsor, hence funding INDEPENDENT.
Study 2 · 2022
- Meta-analysis of randomized trials
- 1,002 participants
- Reputable journal
- Funding not established
moderate68/100Reasonable evidence with real limitations.
Read this first: An SMD of -1.55 is roughly three times the effect size seen for SSRIs in anxiety trials, which is implausible on its face; combined with I-squared of 93.8% and the authors' own "low certainty" GRADE rating, the pooled number should be read as a summary of a biased literature, not as an estimate of benefit. The great majority of the pooled trials were run on manufacturer-supplied branded extracts.
Pooling 12 randomized trials with 1,002 participants, this meta-analysis reported large reductions in anxiety (standardized mean difference -1.55) and stress (SMD -1.75) versus placebo. The authors themselves rated the certainty of that evidence as low, and the heterogeneity between trials was extreme (I-squared 93.8% for anxiety, 83.1% for stress) — effect sizes that large with disagreement that severe usually reflect small biased trials rather than a real drug effect of a size no prescription anxiolytic has ever matched.
How this record was checked
PubMed record 36017529 fetched via NCBI efetch 2026-08-18; title, authors, journal, year, DOI, N=1,002 across 12 trials, SMD values, I-squared values, and the "certainty of the evidence was low" statement confirmed verbatim from the abstract. Europe PMC core record fetched 2026-08-18 returned no grant or funding list, and the publisher page was not retrievable, so funding is recorded UNKNOWN rather than inferred.
Study 3 · 2019
- Randomized trial
- 60 participants
- Indexed journal
- Industry funded
- Preregistered
- Declared conflicts of interest
early signal50/100Suggestive but preliminary. Not settled.
Read this first: Funded by Arjuna Natural Extracts Ltd, the manufacturer of the Shoden extract tested. The authors state the trial was independently managed by the site investigators and the lead author discloses prior funding from the same company for unrelated work, but the sponsor's commercial interest in a positive result is direct, and the study's own secondary psychological outcome (DASS-21) did not reach statistical significance.
Sixty stressed but healthy adults took 240 mg of a standardized ashwagandha extract (Shoden) or placebo daily for 60 days. Anxiety on the Hamilton Anxiety Rating Scale fell more with ashwagandha than placebo (p=0.040), but the broader DASS-21 stress and mood measure did not reach significance (p=0.096); morning cortisol dropped more on ashwagandha. This is a 60-person study in people without a psychiatric diagnosis, funded by the company that makes the extract.
How this record was checked
PubMed record 31517876 fetched via NCBI efetch 2026-08-18; title, authors, journal, year, DOI, N=60, the 240 mg Shoden dose, HAM-A p=0.040, DASS-21 p=0.096, and CTRI registration CTRI/2017/08/009449 confirmed verbatim from the abstract and its conflict-of-interest statement. Europe PMC core record fetched 2026-08-18 lists the funding agency as "Arjuna Natural Extracts Ltd", hence funding INDUSTRY and independent false.
Study 4 · 2012
- Randomized trial
- 64 participants
- Indexed journal
- Industry funded
- Declared conflicts of interest
early signal44/100Suggestive but preliminary. Not settled.
Read this first: The paper's formal declaration reads "Source of Support: Nil" and "Conflict of Interest: None", but its own text states that the high-concentration full-spectrum extract tested "is the KSM-66 Ashwagandha extract, provided by Ixoreal Biomed, Hyderabad, India" — in-kind supply of the investigational product by its manufacturer, which is industry support whatever the declaration says. Recorded here as INDUSTRY on that basis. The trial was also not preregistered and the reported p-values are implausibly uniform across every scale.
The single most-cited ashwagandha trial: 64 adults with chronic stress took 300 mg of KSM-66 root extract twice daily or placebo for 60 days, and the extract group scored significantly lower on every stress scale (p<0.0001) with lower serum cortisol (p=0.0006). It is a 64-person, single-centre, 60-day study in people who were stressed rather than diagnosed, run on extract supplied by the company that sells it, and its results have never been replicated at scale by an independent group.
How this record was checked
PubMed record 23439798 fetched via NCBI efetch 2026-08-18; title, authors, journal, year, DOI, N=64, the 300 mg twice-daily dose, the 60-day duration, and the p-values confirmed verbatim from the abstract. Europe PMC full text (PMC3573577) retrieved 2026-08-18: the supported-by footnote reads "Source of Support: Nil" and the conflict footnote reads "Conflict of Interest: None", while the body text discloses the KSM-66 extract was provided by Ixoreal Biomed — both statements read directly, hence the INDUSTRY call and the contestedNote above.
Study 5 · 2020
- Case series
- 5 participants
- Reputable journal
- Independently funded
- Declared conflicts of interest
early signal53/100Suggestive but preliminary. Not settled.
Five patients (mean age 43) developed jaundice with nausea, lethargy, itching, and abdominal discomfort 2 to 12 weeks after starting ashwagandha-containing supplements; the injury was cholestatic or mixed, itching and high bilirubin persisted for 5 to 20 weeks, and chemical analysis confirmed ashwagandha in the products with no other toxic compounds identified. No one developed liver failure and liver tests normalised within 1 to 5 months in the four patients followed up. Five cases cannot tell you how often this happens, but they establish that it happens.
How this record was checked
PubMed record 31991029 fetched via NCBI efetch 2026-08-18; title, authors, journal, year, DOI, the five cases, the 2-12 week latency, the R ratios 1.4-3.3, and the 1-5 month recovery window confirmed verbatim from the abstract. Europe PMC core record fetched 2026-08-18 lists NIDDK grants U01DK083020, U01DK100928, U01DK083027, U01/U24 DK065176 and no commercial sponsor, hence funding INDEPENDENT; the record's conflict statement reads "The authors have no conflicts of interest to declare."
The Risks
Nobody checks this purchase the way a prescription is checked. No prescriber reviews it against the rest of what you take, no pharmacist screens the interaction, and no regulator confirms the dose in the capsule before it is sold. That is why this section sits here at full length rather than as a footnote.
What the paragraph below covers:
- Liver injury
- Drug interactions
- Fertility and pregnancy
- Sedation
Ashwagandha has been implicated in clinically apparent liver injury: a case series from Iceland and the US NIH-funded Drug-Induced Liver Injury Network documented five patients who developed jaundice, itching, and cholestatic or mixed liver injury 2-12 weeks after starting ashwagandha-containing supplements, and the NIH LiverTox database now lists it as an implicated agent. It can raise thyroid hormone levels — a randomized trial in subclinical hypothyroidism reported increases in T3 and T4, and published case reports describe thyrotoxicosis and painless thyroiditis after use — which matters for anyone with thyroid disease or on levothyroxine. It is generally advised against in pregnancy, and its sedative and immune-modulating properties raise interaction concerns with sedatives, thyroid drugs, and immunosuppressants. The efficacy evidence is a stack of small (typically 60-person), short (8-12 week) trials, most of them run on manufacturer-supplied extract and reported with effect sizes far larger than any prescription anxiolytic achieves — a pattern that usually signals bias rather than a breakthrough. There is no trial evidence in people with a diagnosed anxiety disorder or major depression treated to standard clinical endpoints.
What Is Not Known
The boundaries of the section above, in the harvest’s own words. What it excluded, why, and where it looked and found nothing. An absence of evidence is not evidence of absence, and it is not evidence of benefit either.
What Was Left Out, and Why
Quoted from the harvest, where these notes sat above the study list rather than after it. Where a note says “below” it means the studies in the section above.
- Salve 2019 (Cureus, PMID 32021735, doi 10.7759/cureus.6466) was verified end-to-end but omitted: it duplicates Chandrasekhar 2012 in design, size (n=60), and sponsor (the KSM-66 extract was "manufactured and gifted by Ixoreal Biomed Inc." per the paper's own text), and adds nothing the two entries below do not already show.
- Pratte 2014 (J Altern Complement Med, PMID 25405876) was verified but omitted as superseded by the two 2022 meta-analyses below; its own conclusion — "all studies exhibited unclear or high risk of bias" — is preserved in the contestedNotes here.
- Lopresti 2019 in Am J Mens Health (PMID 30854916, aging overweight men) excluded: the outcome was hormones/vitality, not a mental-health endpoint.
- Individual ashwagandha hepatotoxicity and thyrotoxicosis case reports (e.g. PMID 16355578, PMID 38559552) excluded in favour of the DILIN/Iceland case series below, which is the better-characterised source.
The Retraction Check
PubMed efetch records for all five PMIDs inspected 2026-08-18 for "Retraction in", "Expression of concern", "Erratum in", and "Withdrawn" flags; none present.
Questions for a Prescriber or Pharmacist
This page does not tell anyone to take Ashwagandha or to avoid it. It is not able to: it does not know what else you take, what you have tried, or what you are treating. These are the questions each study above raises, written to be asked out loud.
- The best network meta-analysis puts ashwagandha's anxiety benefit somewhere between almost nothing and about 10 points on a clinical scale — is that uncertain a bet worth taking before we try something with firmer evidence?
- This meta-analysis reports an anxiety effect bigger than anything prescription medication achieves, but rates its own evidence as low certainty — what would you want to see before treating that number as real?
- This trial was paid for by the company selling the extract and ran for 60 days in 60 people without a diagnosed anxiety disorder — does anything about my situation match the people who were actually studied?
- Most of what I've read about ashwagandha traces back to one 64-person study using one company's extract — is there anything larger or independent you'd want to see first?
- If I take ashwagandha, should we check my liver enzymes before I start and again after a couple of months, and what symptoms should make me stop and call you?
And the one to ask at the counter, whatever the answers above turn out to be: given everything I am already taking, what would you want to know about Ashwagandha before I put it in the same body?
Where This Page Comes From
Transcribed from the study-harvest-2026-08-18 record for ashwagandha, built into this page by scripts/supplement-ingest.mjs on 2026-09-07. Nothing here is fetched at page load, and nothing here was written by a model without a citation behind it.
| Source file | study-harvest/2026-08-18/ashwagandha.yaml |
|---|---|
| Source repo | REPTechnologies/avalo-backend |
| SHA-256 | 1faca3fe747dcd96593eeb9698184e4a770f39206d92236b4aecc87ca636df77 |
| Also searched as | Withania somnifera, KSM-66, Sensoril, Shoden, Indian ginseng, winter cherry, ashwagandha root extract |
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