Last updated: October 2026
Ashwagandha (Withania somnifera) is an Ayurvedic herb, mainly taken as a root extract for stress. Small trials suggest it may help a little with stress, anxiety and sleep, but the evidence is low certainty. In the UK it is legal, but the FSA is reviewing its safety, and some people should avoid it.
Ashwagandha at a glance
- What it is
- A root extract of Withania somnifera, a shrub used in Ayurveda
- Main use
- Stress, plus sleep and exercise
- Evidence
- Small, short trials; low certainty
- Trial doses
- About 240 to 600mg of extract a day, often for 8 weeks
- Common side effects
- Stomach upset, diarrhoea, drowsiness
- UK status
- Legal as a food supplement; FSA safety review ongoing
- Avoid if
- Pregnant or breastfeeding, under 18, liver, thyroid or autoimmune conditions
What is ashwagandha?
Ashwagandha (Withania somnifera), sometimes called Indian ginseng or winter cherry, is a small shrub used in Ayurvedic medicine for centuries. Supplements mostly use extracts of the root, standardised to compounds called withanolides. It’s often described as an “adaptogen”, a traditional term for herbs said to help the body cope with stress.
How it might work isn’t settled. The leading idea is that it dampens the body’s stress-hormone system: in one 2019 trial, morning cortisol fell more with ashwagandha than with a placebo. Ashwagandha has no authorised health claims in the UK, so everything below is what research has looked at, not a promise.
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View productWhat does ashwagandha do? The benefits
Most of the research is on stress. Here is what the better studies found, and how much weight they carry.
| Benefit | What trials found | How strong |
|---|---|---|
| Stress and anxiety | Review of 12 trials (1,002 people): lower stress and anxiety scores than placebo | Low certainty |
| Stress hormone | Trial of 60 stressed adults, 60 days: lower anxiety scores and morning cortisol | One small trial |
| Sleep | Review of 5 trials (400 people): small improvement, larger in people with insomnia, at 600mg or more for 8 weeks or longer | Small effect |
| Strength | Trial of 57 men new to weight training, 8 weeks: greater strength and muscle gains | One small trial |
| Testosterone | Rose in men in the 2019 trial, but not significantly more than placebo | Weak |
Most trials were small, short, and often funded by extract makers. Claims you’ll see online about weight loss, memory, thyroid or fertility rest on even thinner evidence. So the fair summary is that ashwagandha may help a little with how stressed people feel, and possibly with sleep, over several weeks.
For more detail, see ashwagandha for anxiety, ashwagandha for sleep: dose and when to take it, ashwagandha for men: testosterone, fertility and strength and ashwagandha for women. Comparing options? Read ashwagandha vs magnesium, ashwagandha vs rhodiola, reishi vs ashwagandha and tulsi vs ashwagandha, or see how ashwagandha ranks against other natural anxiety supplements.
Ashwagandha side effects
In short trials, most healthy adults tolerate ashwagandha well. A 2026 review of 23 trials in healthy adults (2,317 people, up to 180 days) found no serious side effects linked to standardised root extracts, though several of its authors work in the supplement industry. The usual complaints are:
- stomach upset, nausea or diarrhoea
- drowsiness
- headache
Rarer but more serious are cases of liver injury. In one case series from Iceland and the US, five people developed jaundice and itching 2 to 12 weeks after starting ashwagandha products; their liver tests returned to normal within 1 to 5 months where follow-up was available. There are also case reports of thyroid changes. Stop and see your GP if you notice yellow skin or eyes, dark urine or itching. Our ashwagandha side effects guide covers women, men and mood effects in more depth.
Is ashwagandha safe in the UK?
Ashwagandha is not banned in the UK. As of October 2026 it is legal to sell as a food supplement, but its safety is under review:
- 2024: the FSA ran a call for evidence on ashwagandha supplements.
- June 2026: the FSA published a summary of the 19 responses and said the evidence goes to its Committee on Toxicity (COT) for a risk assessment, with the outcome to be published.
- June 2026: the FSA told Which? it would advise people with pre-existing liver conditions and pregnant women to avoid ashwagandha supplements, while saying it could not yet confirm a direct link with liver injury.
- September 2026: the COT discussed a third draft statement on ashwagandha’s safety. It was held in private because it contains unpublished information, and nothing has been published yet.
Elsewhere, Denmark’s food authority banned ashwagandha in food supplements in 2023, after a 2020 assessment by the Technical University of Denmark found no safe intake level could be set; some researchers dispute that conclusion. The US National Center for Complementary and Integrative Health says it may be safe for up to 3 months, but there isn’t enough information on long-term use.
Who should avoid ashwagandha
- anyone pregnant, breastfeeding or trying to conceive (see ashwagandha and breastfeeding)
- under 18s
- people with liver disease, a thyroid condition or an autoimmune condition
- men with hormone-sensitive prostate cancer, and anyone due to have surgery
- anyone taking thyroid, diabetes, blood pressure, sedative, epilepsy or immune-suppressing medicines, unless their GP or pharmacist agrees
For the full timeline, other countries and what could happen next, read our ashwagandha UK safety review.
How to take ashwagandha
- Form: a root extract, with the extract amount and plant part stated on the label.
- Dose: trials mostly used about 240 to 600mg of extract a day. See how much ashwagandha to take per day.
- Timing: evening suits many people; some split it morning and evening. See when to take ashwagandha.
- How long: trials usually ran for about 8 weeks, and the safety data mostly covers up to 3 months. Take breaks rather than using it indefinitely.
How we use ashwagandha
Our Flow CBD Oil is a daytime oil made with broad spectrum CBD, ashwagandha extract and maca root extract in coconut MCT oil, with our Energise terpene blend. If you’d rather avoid ashwagandha, our Broad Spectrum CBD Oil contains only CBD and MCT oil. See CBD and ashwagandha for taking the two together.
Two ashwagandha-free options sit alongside Flow below. Our Magnesium Glycinate Sleep Complex is a berry drink powder; magnesium contributes to a reduction of tiredness and fatigue. Our Reishi Mushroom Adaptogenic Complex is a reishi hot chocolate with cacao and maca, and contains a little natural caffeine from the cacao.
The FSA’s 10mg a day figure is precautionary advice rather than a legal limit, set while longer-term safety research continues. At Evopure we think it is a very cautious figure, and many adults use more. If you go above it, increase slowly, and check with your GP or pharmacist first if you take any medication.
iAll our products are for adults (18+) only. We don’t recommend our products during pregnancy or breastfeeding. If you have a thyroid or autoimmune condition, or take sedatives or any other medicines, check with your GP or pharmacist first.
Choosing an ashwagandha supplement in the UK
Look for a root-only extract, a clear amount of extract per dose, and the withanolide percentage. Seeing KSM-66 on labels? Our KSM-66 ashwagandha guide explains root-only extracts and withanolides. We’ve also checked the labels of popular UK ranges:
- Holland and Barrett ashwagandha: strengths, gummies and KSM-66
- Vitabiotics ashwagandha: is it KSM-66?
- Wild Nutrition ashwagandha: what’s in it and how to take it
- Home Bargains ashwagandha: what to check on a budget label
Deciding between forms? Our guide to ashwagandha gummies vs liquid, capsules and powder compares dose accuracy, sugar and alcohol.
Our guide to how long ashwagandha takes to work sets out each trial’s time points and how to track your own.
Sources 12
- Akhgarjand C et al. Does ashwagandha supplementation have a beneficial effect on the management of anxiety and stress? A systematic review and meta-analysis. Phytother Res, 2022.
- Lopresti AL et al. An investigation into the stress-relieving and pharmacological actions of an ashwagandha extract. Medicine, 2019.
- Cheah KL et al. Effect of ashwagandha extract on sleep: a systematic review and meta-analysis. PLoS One, 2021.
- Wankhede S et al. Examining the effect of Withania somnifera supplementation on muscle strength and recovery. J Int Soc Sports Nutr, 2015.
- Coope OC et al. Safety and tolerability of standardised ashwagandha root extract in healthy adults: a systematic review. Pharmaceuticals, 2026.
- Björnsson HK et al. Ashwagandha-induced liver injury: a case series from Iceland and the US Drug-Induced Liver Injury Network. Liver Int, 2020.
- FSA. Summary of responses to call for evidence on ashwagandha, June 2026.
- COT. Draft minutes of the 8 September 2026 COT meeting (item 5: third draft statement on ashwagandha).
- Which?. Ashwagandha: stress buster or health risk?, June 2026.
- Hayashi M et al. Painless thyroiditis by Withania somnifera (ashwagandha). Cureus, 2024.
- Patwardhan B et al. Danish ban on ashwagandha: truth, evidence, ethics, and regulations. J Ayurveda Integr Med, 2024.
- NCCIH. Ashwagandha.
