Which supplements have real evidence for boosting testosterone?

Testosterone, the main male sex hormone, is essential for muscle growth, bone strength, fat distribution, red blood cell production and sexual health. Because levels tend to fall gradually with age, a large market has emerged for supplements that claim to raise testosterone, restore energy and improve performance. The question is whether any of those products are actually supported by science.

The answer is more complicated than many advertisements suggest. Some supplements do show potential in research, especially for people with particular deficiencies, but the evidence is not strong enough to support broad claims for the general public. What matters most is what the research actually shows, not what marketing promises.

What low testosterone means

Before looking at specific supplements, it helps to define low testosterone. Clinically important low testosterone, also called hypogonadism, is diagnosed when levels drop below 300 nanograms per decilitre (ng/dL) and are accompanied by symptoms such as low libido, erectile dysfunction, reduced muscle mass, higher body fat, fatigue and mood changes.

Age is only one factor in declining testosterone. Obesity, chronic stress, poor sleep, some medications and other health conditions can also play a role. In many cases, improving these underlying issues has a greater effect than taking supplements, even though that receives far less attention in commercial advertising.

Vitamin D and testosterone

Vitamin D, despite being called a vitamin, acts more like a hormone and has one of the clearest scientific links to testosterone production. Several studies have found an association between vitamin D status and testosterone levels.

One major study in Hormone and Metabolic Research reported that men taking 3,332 IU of vitamin D per day for a year had a meaningful rise in testosterone compared with those given a placebo. The increase was about 25% across total, bioactive and free testosterone.

That said, the effect seems strongest in people who are already deficient. Estimates suggest vitamin D deficiency affects a large share of adults, but men with already adequate levels usually see little additional testosterone benefit from supplementation.

Researchers believe vitamin D may influence testosterone through receptors in the testes and pituitary gland, which points to a direct role in hormone regulation. Because deficiency is common and proper-dose supplementation is generally low risk, vitamin D is among the more evidence-backed options for supporting healthy testosterone.

Zinc and magnesium

Zinc is important for testosterone production, and a lack of it has been clearly connected to hypogonadism. Research in Nutrition found that supplementing zinc-deficient men raised testosterone significantly, while restricting zinc in healthy men lowered it.

Those benefits mainly apply when zinc is missing from the diet. Men with enough zinc already tend to see little added testosterone effect from extra supplementation. Athletes and people who sweat heavily may be more likely to run low, which could make supplementation more relevant for them.

Magnesium appears to follow a similar pattern. A study in Biological Trace Element Research found that magnesium supplementation increased both free and total testosterone, especially when paired with exercise. Magnesium also supports many enzyme reactions involved in hormone production.

The well-known ZMA combination, which includes zinc, magnesium aspartate and vitamin B6, has long been promoted to athletes. Some studies are encouraging, but others have found no meaningful testosterone boost, particularly in people without deficiencies. The combination seems most useful for those whose diets are lacking in these minerals.

D-aspartic acid

D-aspartic acid (D-AA) is an amino acid involved in the regulation of testosterone production and release. Early studies attracted attention, including a 2009 trial in which 2.7 grams per day for 12 days increased testosterone by about 42% in men who started with low levels.

Later research has been far less consistent. Studies involving men with normal testosterone, including resistance-trained athletes, generally found no important increase. Some research even suggested testosterone may fall with longer use.

At present, the evidence suggests D-AA may help some men with low testosterone or fertility problems, but it does not appear useful for those with normal hormone levels. More research is needed on dosing, duration and who is most likely to benefit.

Fenugreek

Fenugreek is a traditional herb that has drawn interest for possible testosterone-related effects. Several studies have reported positive findings, including one in Phytotherapy Research that found 600 mg of fenugreek extract daily improved testosterone levels and sexual function in men.

Its possible effects may come from compounds called furostanolic saponins, which could limit testosterone breakdown or increase luteinising hormone (LH), the signal that helps stimulate testosterone production. Fenugreek may also inhibit 5-alpha reductase, the enzyme that converts testosterone to dihydrotestosterone (DHT).

Even so, the research is not uniform. Many studies have been funded by companies with a commercial interest in the results, which raises concerns about bias. More independent studies would help confirm the findings.

Ashwagandha

Ashwagandha, an adaptogenic herb widely used in Ayurvedic medicine, has shown some ability to support testosterone, especially in people under stress. One study in the Journal of the International Society of Sports Nutrition found that 600 mg of ashwagandha root extract daily for eight weeks increased testosterone by around 15% versus placebo.

The effect may be indirect, largely through lowering stress and regulating cortisol. Because chronic stress can push cortisol up and testosterone down, reducing stress may create a more favorable hormonal environment.

Some research also suggests ashwagandha may improve strength, muscle mass and recovery in resistance-trained men, although it is not yet clear how much of that comes directly from testosterone changes.

DHEA

Dehydroepiandrosterone, or DHEA, is a precursor to both testosterone and oestrogen. Since the body produces less DHEA with age, some people have assumed supplementation might raise testosterone.

The evidence is mixed. A few studies have shown small testosterone increases, especially in older men with low DHEA, but many others have found no meaningful effect. DHEA may also carry risks, including prostate enlargement and changes in cholesterol levels.

It is banned by many sports bodies because of its hormone-like activity. Given the inconsistent evidence and possible side effects, it should be used cautiously and preferably with medical supervision.

Supplements with little supporting evidence

Some widely sold supplements do not have convincing evidence for raising testosterone. Tribulus terrestris has repeatedly failed to show a reliable testosterone boost in well-designed studies. Horny goat weed, also known as Epimedium, also lacks strong evidence for such claims.

Boron has shown some early promise, but the research remains limited. Tongkat ali, or Eurycoma longifolia, has produced mixed findings, with some studies pointing to stress reduction but inconsistent effects on testosterone itself.

Lifestyle matters too

Supplements should not distract from the basics. Regular resistance training, enough sleep, stress control, maintaining a healthy body composition and avoiding excessive alcohol can all have a major influence on testosterone.

Research consistently shows that improving these core habits often produces stronger and more lasting results than supplements alone. The best approach is usually a combination of healthy lifestyle choices and, where appropriate, evidence-based supplementation.

Bottom line

There is no simple yes-or-no answer to whether scientifically proven testosterone-boosting supplements exist. Vitamin D, zinc and magnesium have the strongest evidence, especially for people who are deficient. Fenugreek and ashwagandha also look promising, but more independent research is needed.

Still, expectations should remain realistic. Most of these supplements have only modest effects, particularly in men whose testosterone is already normal. They are not a substitute for medical testosterone therapy.

Anyone concerned about low testosterone should start with proper testing and medical advice. Lifestyle changes should come first, with supplements used as a supporting tool rather than the main solution. The most credible supplements are those that correct real nutrient gaps while also supporting overall health.

This content is provided for informational purposes only and is not a substitute for professional advice. AFP editorial staff were not involved in the creation of this content.

Featured Video