Ashwagandha may help some adults sleep slightly better, particularly people who already experience insomnia. The strongest overall review found a modest average benefit rather than a dramatic sedative effect. It also found that results varied according to the extract, dose, duration and people being studied.[1]
That distinction matters. Ashwagandha is often marketed as a simple natural sleep aid, but it is an active herbal supplement with product-to-product differences, possible interactions and limited long-term safety evidence. Here is what the research can reasonably tell us before we decide whether it deserves a place in a sleep routine.
What is ashwagandha?
Ashwagandha, or Withania somnifera, is a plant used in Ayurvedic medicine. Modern supplements commonly contain an extract made from the root, the leaf, or a combination of both. These extracts contain naturally occurring compounds known as withanolides, although they are not the only compounds that may contribute to the plant’s effects.[4]
The word “extract” is important. A capsule containing 300 mg of one standardised extract is not necessarily equivalent to a capsule containing 300 mg of another. Plant part, extraction process, concentration and withanolide content can all change the final product. This makes ashwagandha harder to assess than a single, consistently manufactured compound.
Why is it linked with sleep?
Ashwagandha is commonly promoted as an adaptogen, a broad term used for substances said to help the body respond to stress. Some human trials suggest particular preparations may reduce perceived stress or anxiety. That creates one possible pathway to better sleep for people whose minds remain active at night.[4]
However, this does not prove that ashwagandha works as a direct sedative. Sleep may improve because stress feels more manageable, because a particular extract affects sleep-related processes, or because of several factors acting together. The precise mechanism in humans is not settled.
What does the research show about ashwagandha and sleep?
The most useful overview is a 2021 systematic review and meta-analysis of five randomised controlled trials involving 400 adults. Across those trials, ashwagandha produced a small but statistically significant improvement in overall sleep compared with placebo. The effect appeared more noticeable in participants with insomnia, in studies using at least 600 mg per day and when supplementation continued for at least eight weeks.[1]
The same review reported improvements in mental alertness after waking and anxiety, but no significant improvement in quality of life. No serious adverse events were recorded in the included trials. That sounds reassuring, but the studies were too small and short to rule out uncommon or longer-term problems.[1]
What did the individual trials find?
One trial involved 60 adults with insomnia and anxiety. Participants received either placebo or 300 mg of a standardised ashwagandha root extract twice daily for 10 weeks. The ashwagandha group improved across several sleep measures, including sleep onset latency and sleep efficiency.[2]
Another trial studied 150 healthy adults who reported non-restorative sleep. It tested 120 mg per day of a different root-and-leaf extract for six weeks. Participants taking the extract reported better sleep quality, while wrist-based activity monitoring also indicated improvements in selected sleep measures.[3]
These results suggest that certain ashwagandha preparations may support sleep in some adults. They do not prove that every formulation will work, that higher doses are always better, or that the same effect will continue indefinitely.
How meaningful is the benefit?
Statistical significance does not automatically mean a life-changing result. The pooled benefit in the 2021 analysis was modest. Someone with persistent insomnia may notice an improvement, while someone who already sleeps reasonably well may notice very little.
Results can also depend on what is being measured. Some trials use questionnaires that capture how a participant feels about their sleep. Others use actigraphy, where a wrist-worn device estimates sleep and wake patterns from movement. Both approaches can be useful, but neither provides the same information as a full overnight sleep study.
Placebo effects, changes in routine and natural fluctuations in sleep can also influence short trials. Randomisation and placebo controls reduce these problems, but they do not remove every source of bias. One trial in the meta-analysis was partly sponsored by a manufacturer, and all five trials were conducted in India. Larger independent studies across more diverse populations would give us greater confidence.[1]
Is there a proven dose or best time to take it?
No universal dose has been established for sleep. Trials included in the 2021 review used daily doses ranging from 120 mg to 600 mg, but they did not all use the same extract. Comparing those numbers alone can therefore be misleading.[1]
The review found stronger results in studies using at least 600 mg daily for eight weeks or longer. That is a subgroup finding, not a personalised dosing instruction. It does not show that everyone should take 600 mg or that increasing the dose will improve the outcome. A concentrated extract at a lower mass may deliver a different amount and profile of plant compounds than a less concentrated product at a higher mass.
There is also no well-established best time of day. Study protocols vary, with some splitting the dose and others using it once daily. Product directions and professional advice should take priority over a generic schedule found online.
Why longer use is not automatically better
Most sleep trials lasted six to twelve weeks. Evidence that a benefit appeared after eight weeks does not establish that continuous use for many months or years is safe or more effective. The US National Institutes of Health notes that short-term use appears reasonably well tolerated, but long-term safety remains unclear.[4]
Safety, side effects and who should be cautious
Commonly reported short-term effects include stomach upset, diarrhoea, vomiting and drowsiness. Ashwagandha may also interact with medicines used for diabetes, blood pressure, thyroid function, seizures, sedation and suppression of the immune system.[4]
It should be avoided during pregnancy and breastfeeding. Professional advice is also important for people with thyroid or autoimmune conditions, people preparing for surgery, anyone taking regular medication, and anyone unsure whether a specific formulation suits their health circumstances.[4]
The Australian liver warning
Australia’s Therapeutic Goods Administration advises that ashwagandha may be linked with liver injury in very rare cases. Although most reported Australian cases resolved after the suspected product was stopped, some required medical care or hospitalisation. The TGA advises people with current or previous liver problems to avoid products containing Withania somnifera.[5]
Stop taking the product and seek prompt medical advice if you develop yellowing of the skin or eyes, dark urine, unusual tiredness, weakness, persistent nausea or vomiting, abdominal pain, or loss of appetite. Sudden vomiting or diarrhoea can also represent an acute reaction and warrants stopping the product and arranging assessment.[5]
Can stopping ashwagandha cause withdrawal?
There is no established ashwagandha withdrawal syndrome. Evidence is currently limited to isolated reports rather than controlled studies.
A 2025 case report described one person who experienced anxiety, insomnia and a rapid heart rate after abruptly stopping 600 mg per day. The authors considered withdrawal one possible explanation, but a single case cannot prove cause or tell us how frequently this might occur.[6]
If you have used ashwagandha regularly and are concerned about stopping, speak with a doctor or pharmacist. They can consider the exact product, dose, duration, other medicines and the reason you began taking it. Avoid assuming that a taper is necessary for everyone or that abrupt cessation is always harmless.
A practical way to decide if ashwagandha suits you
- Start with the reason your sleep is poor. A supplement is unlikely to solve an inconsistent schedule, late caffeine, an uncomfortable room or an untreated health issue.
- Set realistic expectations. The average sleep benefit in current research is modest.
- Read beyond the milligrams. Check whether the product uses root, leaf or both, the type of extract, its standardisation and the labelled directions.
- Check your health and medicines first. Ask a doctor or pharmacist when pregnancy, breastfeeding, liver, thyroid or autoimmune concerns, surgery, chronic disease or regular medicines are relevant.
- Track the outcome. Note sleep onset, awakenings, wake time and next-day alertness. This makes it easier to judge whether anything meaningful has changed.
- Do not let a supplement delay assessment. Persistent insomnia, loud snoring, choking or gasping during sleep, marked daytime sleepiness or other concerning symptoms deserve professional attention.
For more practical, evidence-led guidance across sleep, exercise and nutrition, explore the ProActive Health Group health articles.
The takeaway
Ashwagandha is not pure hype, but it is not a guaranteed sleep solution either. Certain extracts may offer a modest benefit, particularly for adults with insomnia, and meaningful changes may take several weeks. The research is still limited by small trials, different formulations and short follow-up periods.
If you are considering it, compare the actual extract rather than the milligrams alone, check whether it is appropriate alongside your health conditions and medicines, and treat new symptoms seriously. Good sleep foundations and proper assessment of persistent problems still matter more than any single supplement.
Sources
- Cheah KL, Norhayati MN, Yaacob LH, Abdul Rahman R. “Effect of Ashwagandha (Withania somnifera) Extract on Sleep: A Systematic Review and Meta-analysis.” PLOS ONE, 2021. View on PubMed.
- Langade D, Kanchi S, Salve J, Debnath K, Ambegaokar D. “Efficacy and Safety of Ashwagandha (Withania somnifera) Root Extract in Insomnia and Anxiety: A Double-blind, Randomized, Placebo-controlled Study.” Cureus, 2019. View on PubMed.
- Deshpande A, Irani N, Balkrishnan R, Benny IR. “A Randomized, Double Blind, Placebo Controlled Study to Evaluate the Effects of Ashwagandha (Withania somnifera) Extract on Sleep Quality in Healthy Adults.” Sleep Medicine, 2020. View on PubMed.
- National Institutes of Health Office of Dietary Supplements. “Ashwagandha: Is It Helpful for Stress, Anxiety, or Sleep?” Fact Sheet for Health Professionals, 2025. View the fact sheet.
- Therapeutic Goods Administration. “Herbal Preparations Containing Withania somnifera (Withania, Ashwagandha).” Australian Government, 2026. View the safety alert.
- Holzman A, Brown AE, Kelley J, Rappaport D, Martini WA. “Unmasking Potential Withdrawal Effects of Ashwagandha: A Case Report and Review.” Cureus, 2025. View on PubMed.
