Ashwagandha is one of the few herbal supplements with several randomized trials in men looking at testosterone, sexual health, semen and strength. Many of those trials are small and short, and some are funded by supplement companies, but the pattern is consistent enough to describe. This guide covers what was found, how big the effects were, and what didn't work. For the general overview of ashwagandha, see our ashwagandha guide.
Testosterone: A Modest Rise
A 2026 systematic review and meta-analysis pooled 23 randomized, placebo-controlled trials (1,706 adults) of ashwagandha and hormone levels. It found testosterone rose in men (about 57 ng/dl, a mean difference) but not in women, and that estradiol didn't change in either Established. A 2021 systematic review of herbs and testosterone in men also found ashwagandha was one of two herbal extracts with positive effects, while noting most studies were in young, healthy men and that evidence was limited by small samples and varied doses.
- In 57 young men starting resistance training, 300mg of root extract twice a day for 8 weeks produced a bigger testosterone rise than placebo.
- In overweight men aged 40–70 with mild fatigue, 8 weeks of a root extract raised testosterone about 14.7% and DHEA-S about 18% more than placebo. But fatigue, vigor and sexual well-being scores didn't differ from placebo.
The takeaway: it nudges testosterone upward in studied groups, but a higher number on a blood test hasn't reliably meant that men felt better. It is not a replacement for testosterone treatment if a doctor has diagnosed low testosterone.
Libido and Sexual Satisfaction
Two randomized, double-blind, placebo-controlled trials of the same design tested 300mg of root extract twice a day for 8 weeks in healthy men aged 30–50 Preliminary:
- 100 men (93 analysed): better sexual desire, orgasm and desire domains of the erectile function questionnaire, and overall satisfaction than placebo, plus higher semen volume, sperm number, concentration and morphology.
- 76 men: better desire scores, more satisfying sexual events and erectile function scores than placebo, with a reported 36% higher ejaculate volume, 38% higher total sperm count and 87% higher sperm motility.
Both reported no adverse events. They're small, short, and the sperm and semen figures come from the trial's own analyses, so treat the percentages as indicative, not guaranteed results. Our ashwagandha for women guide covers libido findings in women.
Erectile Dysfunction: Not Supported So Far
For men with erectile dysfunction, the evidence is poor Not supported so far. In a randomized trial of 86 men with psychogenic erectile dysfunction, 60 days of ashwagandha root powder did no better than placebo: scores improved about 12.6% on ashwagandha and 19.1% on placebo, with no significant difference between the groups, and neither group reached a meaningful improvement. Better desire in healthy men (above) isn't the same as treating ED, and ED can signal heart, diabetes or other health problems that need a doctor.
Fertility and Sperm
A 2018 systematic review of ashwagandha in infertile men found only four clinical trials: one randomized trial and the rest observational. Compared with baseline, sperm concentration, semen volume and motility improved, as did testosterone and luteinising hormone, and no adverse effects were reported. The reviewers' conclusion was that the data are promising but too limited to be robust, and that larger, higher-quality trials are needed Preliminary. If you're trying to conceive and have a semen analysis showing a problem, see a fertility specialist; ashwagandha is at most an add-on to ask about.
Muscle and Strength
Ashwagandha is often sold to gym-goers. A 2026 meta-analysis of resistance-training trials found greater gains in bench-press and lower-body strength and chest circumference than placebo, but no clear effect on body fat. The evidence is small (three trials, 161 people) and statistically fragile: the strength results lost significance under a more conservative analysis, and each depended on one influential trial. The authors rated certainty as low to very low Mixed. So it may help a little, but training, protein and sleep matter far more.
Stress and Sleep
Part of why men feel better on ashwagandha is its stress and sleep effect, which is the best-supported benefit. In stressed adults, 250–600mg a day for 8–9 weeks lowered cortisol and stress scores, and meta-analyses found better sleep, especially in people with insomnia. See ashwagandha for anxiety and stress for the details.
How Much and How Long
| Goal | What the trials used |
|---|---|
| Sexual health, semen, testosterone | 300mg of root extract twice a day (600mg a day) for 8 weeks |
| Stress and sleep | 250–600mg a day for 8 weeks or more |
| Strength training | 300mg twice a day for 8 weeks |
Most trials ran 8 weeks, so judge it after about two months, not days. Nothing in the male trials went above 600mg a day. Our best ashwagandha supplement guide explains what to look for on a label.
Who Should Be Careful
- Thyroid: the same 2026 meta-analysis found thyroxine (T4) rose modestly, and there are thyrotoxicosis case reports. Ask a doctor first if you have thyroid disease.
- Liver: rare cases of liver injury have been reported, and worse outcomes in people with existing liver disease.
- Hormone treatment: if you take testosterone or other hormone therapy, or have a hormone-sensitive condition, ask your doctor, because there's no research on combining them.
- Medications: it may add to sedatives and interact with blood sugar, blood pressure and immune medicines.
The full evidence on risks is in is ashwagandha safe?.
