Ashwagandha and Testosterone: An Australian Evidence Check

Ashwagandha (Withania somnifera) has become one of the most searched-for supplements among men wondering how to lift their testosterone naturally. Testosterone matters for energy, mood, libido, muscle and bone, so it is understandable that men want a simple, over-the-counter option. Ask the internet "does ashwagandha increase testosterone?" and you will find confident claims in both directions. So what does the actual evidence say — and where does a herbal supplement fit for an Australian man worried about low testosterone? Here is a balanced look at the research, its limits, and when it is worth seeing a GP instead.

What is ashwagandha?

Ashwagandha is a herb used in traditional Ayurvedic medicine and is often described as an "adaptogen" — a substance promoted for helping the body cope with stress. In Australia it is sold widely as a complementary medicine, usually as a standardised root extract in capsules or powders, and is commonly marketed for stress, sleep, energy and, increasingly, testosterone and "male vitality". Because chronic stress and poor sleep can genuinely affect hormones, the idea that a calming herb might nudge testosterone is not unreasonable on its face. Marketing claims still need to be checked against evidence, though, so let us look at the best study we have.

What the testosterone research actually shows

The most frequently cited human trial is a 2019 randomised, double-blind, placebo-controlled crossover study published in the American Journal of Men's Health (Lopresti et al., 2019). It looked specifically at ageing, overweight men — middle-aged and older men who were carrying excess weight and reporting some fatigue — rather than young athletes or men diagnosed with a hormone problem. Because it used a crossover design, each participant took both a standardised ashwagandha extract and a placebo (in random order, separated by a washout period), so each man effectively acted as his own comparison.

Over roughly eight weeks of supplementation, the men taking ashwagandha showed a modest rise in testosterone — in the order of 15% compared with placebo — along with a similar increase (around 18%) in DHEA-S, a hormone precursor. The study found no significant change in cortisol (a stress hormone) or oestradiol. Participants also reported some improvement in fatigue and vitality on questionnaires. Taken at face value, that is a genuine, measurable signal, and it is why ashwagandha keeps appearing in "natural testosterone" discussions. But the size and context of that effect matter enormously.

What about energy, stress and libido?

Ashwagandha's traditional reputation is as a calming, anti-stress tonic, and the trial above did measure vitality alongside hormones. Some men in the study reported improvements in fatigue and general vigour while taking the extract (Lopresti et al., 2019). If ashwagandha does help some men feel a little better, part of that may be an indirect effect, because better-managed stress and sleep can support healthier hormone patterns over time. It is worth being cautious, though: vitality and mood are self-reported and easily influenced by expectation, the effects seen were modest, and feeling more energetic is not the same as correcting a testosterone deficiency. If low energy, low libido or low mood are persistent, they deserve a proper look rather than being managed with a supplement alone.

The important limits of the evidence

A single, modest, short-term result is not the same as a proven treatment. Several caveats apply:

• The men were not hypogonadal. They were overweight men with mild fatigue, not men diagnosed with testosterone deficiency. A percentage rise within or towards the normal range is very different from correcting a genuine clinical deficiency.
• It was short and relatively small. The trial ran over a matter of weeks, not years, in a modest number of men. We do not have good long-term data on whether any benefit is sustained or clinically meaningful.
• One product, one dose. The results apply to the specific standardised extract and dose used, not necessarily to whatever ashwagandha product you happen to find on a shelf, which can vary widely in potency and quality.
• "Modest" is the operative word. Even a real 15% shift in men who were not deficient is a long way from the effect of medically supervised testosterone therapy in men who genuinely need it.

In short, the evidence is best described as promising but preliminary. It does not establish ashwagandha as a treatment for low testosterone.

Ashwagandha is not a treatment for low testosterone

This is the most important point for anyone with symptoms. Clinical guidelines are clear that male hypogonadism — clinically low testosterone — is diagnosed on the basis of consistent symptoms plus unequivocally low testosterone confirmed on blood testing, ideally a morning sample repeated to confirm, and that testosterone therapy is reserved for men who meet that definition (Endocrine Society clinical practice guideline, 2018). A herbal supplement does not diagnose anything, is not a substitute for that assessment, and has not been shown to treat hypogonadism.

If your testosterone is genuinely low, the priority is to find out why. Low testosterone can be a signal of other treatable issues — significant excess weight, poorly controlled diabetes, obstructive sleep apnoea, or thyroid and pituitary problems — and some causes are reversible. Reaching for a supplement can simply delay a proper diagnosis. You can read more in our guides to low testosterone symptoms and the blood tests used to check testosterone.

Supplement quality and TGA regulation in Australia

In Australia, ashwagandha is generally sold as a "listed" complementary medicine on the Australian Register of Therapeutic Goods, and it is worth understanding what that does and does not mean. Listed medicines are regulated by the Therapeutic Goods Administration (TGA) for the safety and quality of their permitted ingredients, but they are not individually assessed by the TGA for effectiveness — the regulator does not verify that a given product does what its marketing implies. Potency can also vary between brands, and the amount of active withanolides in a capsule may differ from the extract used in research.

More broadly, the "boost your testosterone" marketplace is a mixed one. Ashwagandha itself is a herbal supplement and is a world away from anabolic-androgenic steroids — but many products and "performance" compounds sold online to raise testosterone or build muscle are unregulated, and some carry well-documented health harms (Pope et al., 2014). A healthy scepticism towards big promises — and a chat with your GP or pharmacist before starting any supplement, especially if you take other medicines or have a thyroid or autoimmune condition — is sensible.

If you have symptoms, get properly assessed

There is nothing wrong with a reasonable, well-made ashwagandha supplement if you are using it to help with stress or sleep, and the testosterone research, while limited, is not nothing. But if you are genuinely worried about low testosterone, the evidence-based path is not the supplement aisle. It is the basics that reliably help — losing excess weight, resistance training, good sleep and moderating alcohol — combined with a proper check-up if symptoms persist. Our guide on how to increase testosterone naturally covers those levers, and if you want to understand how supplements compare with medical treatment, see our piece on testosterone supplements versus TRT.

A telehealth GP can organise the right blood tests, interpret them in context, look for reversible causes, and only consider testosterone therapy where it is clinically appropriate.

The bottom line

• The best human trial to date found ashwagandha produced a modest, short-term rise in testosterone (in the order of 15%) in ageing, overweight men — a real but small signal.
• Those men were not diagnosed with low testosterone, the study was short, and it used one specific extract, so the result should not be over-interpreted.
• Ashwagandha is not a treatment for hypogonadism, which is diagnosed and managed medically on the basis of symptoms plus confirmed low testosterone.
• In Australia it is sold as a listed complementary medicine — assessed for safety and quality, but not for effectiveness — so choose reputable products and be wary of unregulated "testosterone boosters".
• If you have symptoms of low testosterone, see a GP and get tested rather than relying on a supplement.

References

1. Lopresti AL, et al. A Randomized, Double-Blind, Placebo-Controlled, Crossover Study Examining the Hormonal and Vitality Effects of Ashwagandha (Withania somnifera) in Aging, Overweight Males. Am J Mens Health. 2019;13(2). https://pubmed.ncbi.nlm.nih.gov/30854916/
2. Bhasin S, et al. Testosterone Therapy in Men With Hypogonadism: An Endocrine Society Clinical Practice Guideline. J Clin Endocrinol Metab. 2018;103(5):1715-1744. https://pubmed.ncbi.nlm.nih.gov/29562364/
3. Pope HG Jr, et al. Adverse Health Consequences of Performance-Enhancing Drugs: An Endocrine Society Scientific Statement. Endocr Rev. 2014;35(3):341-375. https://pubmed.ncbi.nlm.nih.gov/24423981/

This article is general information only and is not a substitute for personalised medical advice. Testosterone is a prescription-only (S4) medicine in Australia and is prescribed only where clinically appropriate. Speak with an AHPRA-registered GP about your individual situation.