Of all the herbs sold for testosterone, ashwagandha has the most credible research behind it. That’s a low bar in this category, but it’s not nothing — and it deserves a more careful answer than either the supplement industry or its critics usually give.

What it is

Withania somnifera, used in Ayurvedic medicine for a long time, classed as an adaptogen — a loose term for substances claimed to help the body handle stress. The proposed mechanism for any hormonal effect runs through cortisol: lower chronic stress hormone, less suppression of testosterone.

That mechanism is plausible. Whether it produces a clinically meaningful change is the actual question.

What the trials found

Several small randomised controlled trials have measured testosterone in men taking ashwagandha, and the pattern is reasonably consistent: modest increases, concentrated in specific groups.

Men under significant stress. Trials in chronically stressed men have found reductions in cortisol alongside small rises in testosterone. These are the most coherent results, and they fit the proposed mechanism.

Men with fertility problems. Studies in men with low sperm counts or infertility have reported improvements in sperm parameters and some rise in testosterone. Promising, though these are small studies in a specific population.

Men doing resistance training. A few trials alongside structured training programmes reported greater testosterone increases than training alone. Effect sizes are modest and separating supplement from training is difficult.

Healthy men with normal levels. Thinner evidence, and what exists suggests less effect. Consistent with the pattern across this whole field: interventions work best in people who have something to correct.

The caveats that matter

Most of these trials are small — often fewer than a hundred participants — and short, typically eight to sixteen weeks. Many were funded by supplement manufacturers, which doesn’t invalidate them but does warrant caution.

Extract type and dose also vary considerably between studies, so results aren’t directly transferable to whatever is on a shop shelf. And crucially, the increases reported are modest. Nothing in this literature suggests ashwagandha will take a man from clinically low testosterone into a normal range. That is a different order of effect.

Safety

Generally well tolerated over the short term. Stomach upset and drowsiness are the common complaints. There have been case reports of liver injury, rare but documented, and it may interact with thyroid medication, sedatives, immunosuppressants and some blood pressure medicines.

It should be avoided in pregnancy, and anyone with thyroid or autoimmune conditions should check before starting. Long-term safety beyond a few months isn’t well characterised.

If you take regular medication, ask a pharmacist before adding it. This is exactly the sort of thing worth a two-minute conversation.

A reasonable conclusion

If you’re under sustained stress and want to try it, the evidence isn’t unreasonable and the risk is low — assuming no interactions. Buy from a reputable Australian supplier, since product quality varies and imported supplements have been found adulterated.

What it won’t do is resolve clinically low testosterone. If you have persistent symptoms, the useful step is finding out what your levels are, not spending three months hoping a capsule shifts them. You can do both, but don’t let one delay the other.

This article is general information, not medical advice. Speak to a doctor or pharmacist before starting any supplement, particularly if you take other medicines.