Herb

Ashwagandha

Also known as Withania somnifera

Adaptogenic root herb whose withanolide compounds are thought to blunt HPA-axis cortisol release; clinical trials link standardised extracts to reduced perceived stress and anxiety scores.

3linked conditions

21linked studies

On this pageEvidence Availability Outcomes & conditions →

Evidence

What the research actually shows

We link to relevant studies and leave interpretation to you and your healthcare professional.

Evidence analytics

Where the evidence is concentrated

Number of audited published findings for Ashwagandha by condition. Drill into a pair page for the full breakdown.

Putative uses

Where people report using it and what trials suggest

Moderate evidencePerceived stress / anxiety reduction
Moderate evidenceSleep quality
Weak evidenceModest strength/recovery support

Where the evidence is negative

Common claims the trials do not support

Cognitive-benefit claims are poorly supported in healthy adults.
Trials are mostly small, short (6-12 weeks), and industry-affiliated; effect sizes shrink with rigour.
Rare reports of liver injury and thyroid stimulation.

Adaptogenic herb (Withania somnifera) with multiple small RCTs showing reduced perceived stress and cortisol; trial quality is variable and long-term safety data limited.

Safety notes: Avoid in pregnancy. Caution with thyroid conditions and sedatives. Cycle rather than continuous long-term use.

Evidence grades reflect study quality and consistency, not marketing claims.

21studies referenced

19journals

2016–2026publication range

01Effects of ashwagandha (Withania somnifera) on mental health in adults: A systematic review and dose-response meta-analysis of randomized controlled trialsAlsanie SA, et al. · Complementary therapies in medicine · 2026PMID 41644067 ↗02Efficacy and Safety of Herbal Supplements with Anxiolytic, Antidepressant, and Sedative Action: A Review of Clinical Data and Toxicological RisksCăuș MN, et al. · Pharmaceuticals (Basel, Switzerland) · 2026PMID 41901246 ↗03Exploring Phytoleads and Traditional Herbal Therapies: A Comparative Review on Stress ManagementRathee S, et al. · Current pharmaceutical design · 2026PMID 41919431 ↗04Herbal Medicines in Autism Spectrum Disorder: Therapeutic Potential, Plant Components, and Dosage GuidelinesAldekhail NM, et al. · Alternative therapies in health and medicine · 2025PMID 40768551 ↗05Integrative sleep management: from molecular pathways to conventional and herbal treatmentsEbrahim YM, et al. · Naunyn-Schmiedeberg's archives of pharmacology · 2025PMID 40338321 ↗06Effects of Ashwagandha (Withania Somnifera) on stress and anxiety: A systematic review and meta-analysis

Search PubMed ↗Find clinical trials ↗

What trials found, in numbers

Summaries of published trial results for this compound, grouped by condition. Numbers are reported exactly as the researchers published them — we never calculate or convert.

How to read this table

Benefit: What the trial saw happen: whether the measured outcome moved in the helpful direction in that one study (the tag on each row: “Benefit seen”, “No clear benefit” or “Unclear”). It is a study result — not advice, and not a promise it will work for you.
Evidence: How strong the research behind that result is. A meta-analysis pools many studies (strongest); a systematic review collates them; an RCT tests against a control (placebo); observational studies only watch — they can suggest, not prove.
Effect size: How large the measured change was, exactly as the researchers published it. “No number reported” means the abstract gave no effect size — we never invent one.

In short: benefit is what was observed; evidence is how much you should trust the observation. A “Benefit seen” tag on a weak study counts for far less than the same tag on a meta-analysis.

Anxiety (15 outcomes)

Outcome measured	What trials found	Effect size	People studied	Duration	Type of evidence	Study
anxiety	Anxiety scores improved with SMD -1.55 vs placebo in 1,002 people. (95% CI: -2.37, -0.74; p = .005; I2 = 93.8%)Benefit seen	-1.55 SMD	1,002	—	Meta-analysis · 2022	PMID 36017529
stress level	Stress levels improved with SMD -1.75 vs placebo in 1,002 people. (95% CI: -2.29, -1.22; p = .005; I2 = 83.1%)Benefit seen	-1.75 SMD	1,002	—	Meta-analysis · 2022	PMID 36017529
anxiety level	Ashwagandha improved anxiety levels versus placebo in 400 participants, though no specific effect size was reported.

Outcomes & conditions

Why people look into Ashwagandha — and what they report

Associated conditions and community-reported outcomes, wrapped together on one page. Aggregates appear only once enough reports arrive.

Outcomes & conditions →

Important: This page reflects observational, aggregate-only community reporting and independent published research. It is not medical advice, and it does not claim any compound treats, cures, or is effective for any condition. Always consult a qualified healthcare professional before starting, stopping, or changing any supplement or treatment.

Availability

Where to get Ashwagandha (UK)

How this compound is sold in the UK, and where our readers typically find it.

Retailer search links — we may earn commission on purchases at no cost to you. Commission never affects our evidence ratings.

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Outcome measured	What trials found	Effect size	People studied	Duration	Type of evidence	Study
Chalder Fatigue Scale	Ashwagandha significantly reduced fatigue symptoms compared to placebo in adults over 12 weeks. (p=0.016)Benefit seen	no number reported	—	12-week	RCT · 2023	PMID 37740662
Free testosterone	Ashwagandha significantly increased free testosterone in men compared to placebo over 12 weeks. (p=0.048)Benefit seen	no number reported	—	12-week	RCT · 2023	PMID 37740662
Heart rate variability	Ashwagandha significantly increased heart rate variability compared to placebo in adults over 12 weeks. (p=0.003)Benefit seen	no number reported	—	12-week	RCT · 2023	PMID 37740662
Luteinizing hormone	Ashwagandha significantly increased luteinizing hormone in men compared to placebo over 12 weeks. (p=0.002)Benefit seen	no number reported	—	12-week	RCT · 2023	PMID 37740662
Perceived Stress Scale	Ashwagandha did not significantly reduce stress levels compared to placebo in adults over 12 weeks. (p=0.867)No clear benefit	no number reported	—	12-week	RCT · 2023	PMID 37740662
perceived well-being (energy, mental clarity, sleep quality, stress)	Ashwagandha improved perceived well-being vs placebo in 60 college students over 30 days.Benefit seen	no number reported	60	30 days	RCT · 2022	PMID 35984870