Ashwagandha Benefits for Women and Men: What the Research Shows

Ashwagandha went from an obscure Ayurvedic root to the most-searched adaptogen in Britain in about five years. That kind of growth attracts loose claims, so this guide does the opposite: it goes through what has actually been measured in humans, how big the effects were, and where the evidence is weakest.

It also covers something most articles skip — why a UK supplement label cannot repeat any of it.

Stress and cortisol: the best-evidenced use

This is where the research is deepest. A 2025 systematic review and meta-analysis published in BJPsych Open searched PubMed, Web of Science, Scopus and Cochrane through September 2024 for randomised controlled trials in adults with stress or anxiety, comparing ashwagandha against placebo or active treatment on validated measures. Fifteen studies with 873 patients met the criteria^[1].

At eight weeks the pooled results showed a reduction on the Perceived Stress Scale of 4.88 points (95% CI −7.84 to −1.91, p = 0.0013) and a reduction in cortisol of 2.36 (95% CI −3.26 to −1.46, p < 0.0001). Quality of life did not significantly improve (p = 0.3698)^[1].

A 2024 meta-analysis in the Journal of Integrative and Complementary Medicine reached the same direction across nine RCTs in 558 patients: Perceived Stress Scale −4.72 (95% CI −8.45 to −0.99), Hamilton Anxiety Scale −2.19 (95% CI −3.83 to −0.55) and serum cortisol −2.58 (95% CI −4.99 to −0.16) against placebo. Doses ranged from 125 mg to 600 mg daily over 30 to 90 days, using both root-only and root-plus-leaf extracts^[2].

The effect sizes side by side

Two independent meta-analyses, different trial sets, similar answers. That consistency is the reason ashwagandha is taken seriously at all.

Sources: BJPsych Open 2025 meta-analysis; Journal of Integrative and Complementary Medicine 2024 meta-analysis.

Sleep: a smaller, separate evidence base

Sleep is often bundled into "ashwagandha benefits" as if it were the same finding. It is not. A 2021 systematic review and meta-analysis in PLOS ONE pooled five randomised controlled trials in 400 adults and found a small but significant effect on overall sleep (SMD −0.59; 95% CI −0.75 to −0.42), more prominent in adults diagnosed with insomnia, at doses of 600 mg per day or more, and over eight weeks or longer^[3].

Five trials and 400 participants is a much thinner base than the stress literature. We go through it properly in ashwagandha for sleep.

Ashwagandha benefits for women — and for men

"Ashwagandha benefits for women" is one of the most-searched supplement phrases in the UK, so it is worth being precise: the trials behind the numbers above enrolled both women and men, and neither meta-analysis reported a meaningful difference in response between the sexes. The measured effects — lower perceived-stress scores and lower cortisol — were found in adults generally, not in one sex.

Where the questions become women-specific, the honest answers are shorter. There is no good trial evidence for ashwagandha in menopause or for hormonal symptoms, and it should not be taken at all during pregnancy or while breastfeeding. Side effects reported by women in the trials were the same mild, mostly digestive complaints reported by men. If you take thyroid medication — a group in which women are over-represented — speak to your GP first, because ashwagandha may affect thyroid hormone levels.

For men, the research picture on testosterone is thinner than social media suggests: a handful of small, short trials report modest changes, they disagree with each other, and no regulator has accepted the claim. The stress and cortisol findings above remain the best-evidenced reason either sex takes it. Many readers pair it with Lion’s Mane for daytime focus — we cover that mushroom’s evidence separately in our guide to Lion’s Mane.

How long it takes

Almost every positive trial ran for weeks, not days. The stress meta-analyses measured outcomes at eight weeks^[1], with individual trials running 30 to 90 days^[2]; the sleep effect was more prominent in trials of eight weeks or longer^[3].

If you expect something noticeable in the first week, the research does not support that expectation. Our guide to how long ashwagandha takes to work maps out what the trials actually observed week by week.

The scale of both the interest and the doubt is measurable. In our analysis of 8,048 UK supplement searches, “ashwagandha benefits” carries a demand index of 46,183 against 9,933 for “ashwagandha side effects” — roughly one reader in six is checking for the downside, which the next section takes seriously.

The honest caveats

Three limitations matter, and they are not small.

Heterogeneity is very high. A 2022 meta-analysis in Phytotherapy Research covering 12 papers and 1,002 participants found large reductions in anxiety (SMD −1.55) and stress (SMD −1.75), but with I² values of 93.8% and 83.1%^[4]. Figures that high mean the trials disagreed substantially, so pooled point estimates should be read as a direction rather than a precise number.

Certainty of evidence is low to moderate. A 2026 dose–response meta-analysis of 22 RCTs concluded the evidence shows promise but that heterogeneity and imprecision warrant more high-quality trials^[5].

Long-term safety data are limited. Four of the nine trials in the 2024 review reported mild to moderate adverse events, and the reviewers noted that long-term safety data remain insufficient^[2].

Why no UK label can say any of this

Botanical health claims, including those for ashwagandha, sit "on hold" on the GB Nutrition and Health Claims Register — they have not been through the authorisation process that nutrient claims have^[6]. A UK food supplement therefore cannot state that ashwagandha reduces stress, however the meta-analyses read.

Where a UK ashwagandha product does make a permitted claim, it comes from an added nutrient. Vitamin B6 contributes to normal psychological function; vitamin B12 contributes to the reduction of tiredness and fatigue. Those are authorised sentences with defined conditions of use, which is why you see them on labels alongside the botanical.

It is worth reading product pages with that in mind. A brand promising that a botanical will fix your stress is either unaware of the rules or ignoring them.

KSM-66 and why extract standardisation matters

"Ashwagandha 500 mg" tells you the weight of material, not what is in it. Extracts differ by plant part (root only, or root plus leaf), extraction method, and standardised withanolide content. The 2024 review explicitly noted that its included trials used both root-only and root-plus-leaf formulations^[2] — meaning "ashwagandha" in the research is not one single substance.

KSM-66 is a root-only, standardised extract with its own trial record, which is why brands that use it name it rather than saying "ashwagandha extract".

Buying ashwagandha in the UK: what the label must tell you

Ashwagandha is sold in the UK as a food supplement, and the label discloses more about quality than any advert. Five checks do most of the work:

• A named, standardised extract — KSM-66 or another branded extract, with the standardisation stated, rather than "ashwagandha powder" of unspecified strength
• Root-only sourcing — leaf is cheaper to harvest and chemically different; root is the material the research used
• Dose per serving — and how many gummies or capsules that serving is, so a headline figure cannot hide a two-capsule dose
• What the label may lawfully say — no authorised UK health claim exists for ashwagandha, so a compliant label describes the extract, not outcomes
• A UK address and English labelling — listings written for other markets are often not compliant here

Where Vitgem fits

Our ashwagandha gummies provide 2500 mg of KSM-66 across a two-gummy daily serving, alongside Lion's Mane, Ginkgo Biloba and vitamins B6 and B12. The B vitamins are the part carrying authorised claims; the botanicals are stated by dose and standardisation, without a promised outcome.

Our Night-Time Sleep Gummies contain a smaller 50 mg dose of ashwagandha extract as one component of an evening formula — well below the 600 mg used in the sleep trials, which is worth knowing before you choose between them.

Frequently asked questions

What does ashwagandha actually do?

In randomised trials the most consistent measured effects are reductions in perceived stress scores and in cortisol, alongside reductions on anxiety scales. Two independent meta-analyses covering 873 and 558 adults found similar effect sizes. Effects on quality of life were not significant in the larger analysis.

How much ashwagandha should I take?

Trials in the 2024 meta-analysis used doses from 125 mg to 600 mg daily over 30 to 90 days. The sleep meta-analysis found effects more prominent at 600 mg or more. Follow the dose on the product you buy and do not exceed it.

How long does ashwagandha take to work?

The stress meta-analyses measured their outcomes at eight weeks, and individual trials ran 30 to 90 days. This is a slow-acting ingredient in the research, not a same-day one.

Is ashwagandha safe to take long term?

Long-term safety data are limited. Four of nine trials in a 2024 review reported mild to moderate adverse events, and the reviewers noted insufficient long-term safety evidence. Speak to a GP or pharmacist before use if you are pregnant, breastfeeding, taking medication or under medical supervision.

Why doesn't the label say ashwagandha reduces stress?

Because botanical health claims sit on hold on the GB Nutrition and Health Claims Register. A UK food supplement cannot make a health claim that has not been authorised, regardless of what published trials show.

Is KSM-66 different from ordinary ashwagandha?

Yes, in a practical sense. KSM-66 is a root-only extract standardised to a defined withanolide content with its own trial record. Trials in the wider literature have used both root-only and root-plus-leaf preparations, so "ashwagandha" in research is not a single standardised substance.

Does the NHS recommend ashwagandha?

No. The NHS does not recommend individual supplements, and ashwagandha holds no authorised health claim in Great Britain — botanical claims sit on hold while they are assessed. NHS-facing guidance is caution-led rather than promotional: it flags interactions with thyroid, blood-pressure and sedation medicines, avoidance in pregnancy, and rare liver-injury reports. That caution — not endorsement — is the official position, and it is why this article reports trial data with citations rather than promising outcomes.

What should you never mix with ashwagandha?

The standing cautions: speak to a doctor or pharmacist before combining ashwagandha with medication for blood pressure, blood sugar, thyroid function or sedation, and before any planned surgery; avoid it in pregnancy and while breastfeeding; take medical advice first with a thyroid or autoimmune condition. Stop and seek advice if you notice yellowing skin or eyes, unusual tiredness or abdominal pain. Rare liver-injury reports sit behind the caution — infrequent, but worth knowing before you start.

This article summarises published research on ashwagandha and is general information, not medical advice. Food supplements are not a substitute for a varied, balanced diet and healthy lifestyle. Speak to your GP or pharmacist before starting a new supplement if you are pregnant, breastfeeding, taking medication or under medical supervision.

Should women take ashwagandha every day?

Trials used daily dosing for six to twelve weeks, in women and men alike, and that is how any effect was measured. Daily use is how it is intended to be taken — but not during pregnancy or breastfeeding, and check with a GP first if you take thyroid or sedative medication.

Do I take ashwagandha in the morning or at night?

The trials did not compare timing, so there is no evidence that one is better. Consistency matters more than the clock: pick the time you will actually remember. Morning suits people taking it alongside a working day; evening suits those who prefer it as part of winding down.

Related reading

• How Long Does Ashwagandha Take to Work?
• Ashwagandha for Sleep UK: What the Research Shows
• Natural Sleep Aids UK: An Evidence-Based Guide
• L-Theanine for Sleep: What the Research Shows