Does Ashwagandha Work?

The myth and the verdict

The myth is that ashwagandha simply "works" because it is an adaptogen. That is partially true, but too broad. The better verdict is narrower: ashwagandha has plausible, trial-backed benefits for perceived stress and sleep in some adults, while many of the bigger wellness claims outrun the evidence. It is also not automatically safe because it is botanical. Short-term use looks tolerable in many trials, but rare liver injury reports have become consistent enough that safety needs to be part of the decision, not a footnote.1, ⁴, ⁶

This is a category problem. Ashwagandha is not one intervention. Studies use different roots, extracts, withanolide concentrations, doses, and outcome measures. A positive trial of one standardized extract for stress does not prove that every gummy, powder, or multi-ingredient blend will do the same thing. It also does not prove long-term safety.

What the trial evidence actually says

For stress and anxiety-like symptoms, the evidence leans positive, but not definitive. A 2024 systematic review and meta-analysis of randomized trials concluded that ashwagandha improved psychosomatic functions related to stress and anxiety, while also noting variation in preparations and study designs.1 A 2025 systematic review focused on cortisol, stress, and anxiety in adults similarly found improvements across included randomized trials, but the evidence base remained heterogeneous.²

For sleep, the evidence is also more credible than the marketing average. A PLOS One systematic review and meta-analysis found that ashwagandha extract improved sleep outcomes compared with control, with the clearest signal in people with insomnia and at doses of 600 mg per day or higher in some analyses. The same review cautioned that serious adverse effect data were limited and that more safety data are needed for long-term use.³

For testosterone and sexual health, the evidence is thinner. NCCIH describes limited evidence that taking ashwagandha for 2 to 4 months may increase testosterone levels and sperm quality, but that is not the same as proving meaningful improvements in vitality, muscle gain, fertility, or sexual function for the average user.⁶ A 2025 randomized trial in healthy adult men reported sexual health improvements after 8 weeks of root extract, but it is one trial in a defined population, not a universal result.7

For athletic performance, cognition, diabetes, menopause, female infertility, asthma, and broad immune support, the public-facing claims are ahead of the evidence. NCCIH states that there is not enough evidence to determine whether ashwagandha is helpful for several of those conditions.⁶ That does not mean every claim is false. It means the evidence has not cleared the bar for confident advice.

The mechanism sounds plausible, but it does not settle the question

The common mechanism story is that ashwagandha helps the body regulate stress physiology, especially cortisol and related neuroendocrine signaling. That is plausible. Several human studies measure cortisol, perceived stress, anxiety scales, and sleep outcomes, and some show movement in the expected direction.²

The gap is that a plausible mechanism is not the same as a reliable clinical effect. Cortisol can change without a person sleeping better, feeling calmer, or functioning better. Stress scales can improve in short studies without proving durable benefit. Botanical extracts can also contain different active compounds depending on cultivation, processing, and standardization. Mechanism helps explain why the supplement might work. It does not tell you whether your product, at your dose, for your problem, is worth taking.

The same applies to safety. A supplement can have calming effects and still create problems in rare users. Liver injury linked to ashwagandha appears idiosyncratic, meaning it is not easily predicted from dose alone. In the Iceland and U.S. Drug-Induced Liver Injury Network case series, five cases were attributed to ashwagandha-containing supplements, with a pattern that included jaundice and cholestatic or mixed liver injury.⁴ A 2026 scoping review described a reproducible syndrome of idiosyncratic, frequently cholestatic, ashwagandha-associated liver injury, including severe outcomes in vulnerable patients.5

Why the myth persists

The myth persists because the kernel of truth is real. If a person takes ashwagandha during a stressful month, sleeps better, and feels calmer, that experience is meaningful. It is also easy to generalize. A supplement that helps one stress-related outcome becomes a product said to support hormones, workouts, focus, immunity, mood, and aging.

Marketing also compresses evidence. "Shown in clinical studies" can refer to a small, short trial with one extract. The consumer sees a broad promise. The study may have tested a narrow outcome in a narrow population. Multi-ingredient products make this worse because the label highlights ashwagandha while the trial evidence, if any, may not match the formula.

Traditional use adds another layer. Ashwagandha has a long history in Ayurvedic practice, which supports why researchers study it, but traditional use does not answer modern questions about concentrated extracts, daily long-term use, drug interactions, pregnancy, liver disease, or online products with variable quality. A plant used historically in one context can behave differently as a high-dose standardized extract sold for everyday self-treatment.

What is true nearby

The fair position is not "ashwagandha is useless." The fair position is: consider it a stress and sleep supplement with incomplete safety data, not a cure-all. If you are a healthy adult considering it for short-term stress or sleep, the evidence gives you a reasonable basis to try a standardized single-ingredient product, ideally for a defined period, while watching for side effects.

Safety should shape that trial. NCCIH says ashwagandha may be safe short term, up to about 3 months, but long-term safety is not established. It also lists possible side effects such as drowsiness, stomach upset, diarrhea, and vomiting, and advises avoiding it during pregnancy and breastfeeding.⁶ NCCIH also flags cautions for people with autoimmune or thyroid disorders, upcoming surgery, hormone-sensitive prostate cancer, and possible interactions with diabetes drugs, blood pressure drugs, immunosuppressants, sedatives, anti-seizure medications, and thyroid hormone medications.⁶

The liver caveat is the one people miss. It is rare, but it is not imaginary. Stop using ashwagandha and seek medical advice if you develop jaundice, dark urine, severe itching, unusual fatigue, right upper abdominal pain, or pale stools. If you already have liver disease, the risk-benefit case is weak. Germany's Federal Institute for Risk Assessment has advised children, pregnant and breastfeeding people, and people with acute or pre-existing liver disease to avoid ashwagandha supplements, and it cautions that a safe intake level cannot currently be derived from available data.⁸

The practical answer: ashwagandha can be worth a cautious, time-limited trial for stress or sleep. It should not be treated as a harmless daily default, and it should not be used to replace care for anxiety, insomnia, hormonal problems, fertility concerns, or liver symptoms.