Best Supplements for Testosterone, Ranked by Evidence

23 supplements · 1 outcomes · 40 trials

Our #1 pick

Tongkat Ali (Eurycoma longifolia) Likely helps Strong · 69

The strongest direct testosterone signal in the supplement aisle

200 to 400 mg of standardized hot-water extract daily. Most trials used 200 mg; the 2021 multicentre trial found 200 mg outperformed 100 mg for total testosterone.

4 to 12 weeks. The stress-hormone study saw cortisol and free testosterone shift within 4 weeks. The multicentre trial measured total testosterone gains at 12 weeks.

The testosterone supplement market is one of the most overhyped corners of the supplement industry. Walk into any nutrition store and you'll find shelves of products promising to "naturally boost T" with proprietary blends of exotic herbs, amino acids, and minerals. Most of them don't do anything measurable.

That's the bad news. The good news is that a handful of supplements have been tested in randomized, placebo-controlled trials where researchers actually measured serum testosterone before and after. Some of them work, some of them work only for specific populations, and some of the most popular ones are total duds.

This ranking is based on clinical trial evidence in men, not animal studies, not in vitro experiments, and not marketing claims. We prioritize supplements with multiple independent trials, meaningful effect sizes, and populations that actually apply to the person reading this. A supplement that raises testosterone in infertile men with severe oxidative stress may not do anything for a healthy 35-year-old.

One important caveat: if your testosterone is genuinely low (below 300 ng/dL), you should be talking to a doctor about TRT, not browsing supplement aisles. Supplements can nudge hormones in people with mild decline or suboptimal levels, but they're not a replacement for medical treatment when levels are clinically deficient.

#1 deep dive

Why Tongkat Ali (Eurycoma longifolia) takes the top spot

How it works

Tongkat Ali appears to act on the hypothalamic-pituitary-gonadal axis, reducing cortisol and improving the testosterone-to-cortisol ratio.⁴ One proposed mechanism involves quassinoids (particularly eurycomanone) stimulating Leydig cell testosterone production while simultaneously lowering cortisol's suppressive effect on the HPG axis.⁶

What the research says

A 2022 meta-analysis pooling data from five trials in men found a significant increase in serum total testosterone, with the strongest effects in men who started with low levels.⁶ A 2021 multicentre RCT in men aged 50 to 70 with testosterone below 300 ng/dL found that 200 mg daily raised total testosterone and improved aging-male symptom scores over 12 weeks.⁵ An earlier trial in moderately stressed adults reported a 37% increase in free testosterone alongside a 16% drop in cortisol exposure after just 4 weeks.⁴ The effect is more pronounced in men with suboptimal baseline levels than in healthy young men.⁶

Best for

Men over 40 with declining testosterone or men under chronic stress. The evidence is strongest when baseline levels are already low. Healthy young men with normal testosterone should not expect dramatic changes.

Watch out

Not recommended for people with hormone-sensitive cancers (prostate, breast). Some in vitro evidence of CYP2C8 inhibition, which could affect certain medications. Avoid during pregnancy.

Pro tip

Look for standardized hot-water root extracts (Physta is the most-studied brand). The eurycomanone content matters more than raw milligrams. Pair with stress management for a double hit on the cortisol side.

Evidence by outcome

Boost testosterone levels Likely helps

Raises total or free testosterone, especially when baseline levels run low.

d=1.86 Large effect 6 endpoints trust 69

Ashwagandha (Withania somnifera)

Early data

Limited · 48 Small effect

Lowers cortisol first, then testosterone follows

300 to 600 mg daily of a standardized root extract. KSM-66 and Shoden are the most-studied forms for hormonal endpoints.

8 to 16 weeks. Most testosterone-specific RCTs ran 8 weeks; the crossover trial used two 8-week periods.

Full breakdown

How it works

Ashwagandha's primary hormonal mechanism runs through cortisol reduction. Chronic stress suppresses the HPG axis, and by lowering cortisol (confirmed across a 2026 meta-analysis of 17 RCTs), ashwagandha removes a brake on testosterone production.¹⁹ Withanolides also show direct effects on steroidogenic enzymes in preclinical models, though the cortisol pathway appears to be the dominant driver in humans.¹⁷

What the research says

A 2026 meta-analysis pooling data from 1,706 participants across 17 RCTs confirmed that ashwagandha significantly increases total testosterone in men.¹⁹ A crossover trial in overweight men aged 40 to 70 found salivary testosterone rose significantly during the ashwagandha period versus placebo.¹² A 2019 trial in stressed adults showed testosterone increased in men, though the overall mixed-sex analysis was not significant.¹³ Two 2025/2026 RCTs in men with sexual dysfunction confirmed testosterone increases alongside improvements in sexual function, sperm quality, and quality of life.¹⁷¹⁸²⁰ The effect size is smaller than Tongkat Ali, but the evidence base is much deeper, with 12 studies and over 900 participants.¹⁹

Best for

Men dealing with chronic stress, poor sleep, or training-related fatigue. Ashwagandha's cortisol-lowering effect means the testosterone benefit is partly a downstream consequence of stress reduction. If stress is dragging your T down, this addresses the root cause.

Watch out

Rare cases of liver injury have been reported. Ashwagandha can affect thyroid hormone levels (T3/T4), so people on thyroid medication should consult their doctor. It has sedative properties and can interact with benzodiazepines and sleep medications.

Pro tip

Take with food. If you're also dealing with sleep issues or anxiety, ashwagandha pulls double duty. The testosterone benefit is a bonus on top of the well-established stress and sleep effects.

Evidence by outcome

Boost testosterone levels Early data

d=0.33 Small effect 13 endpoints trust 48

N-Acetyl Cysteine (NAC)

Likely helps

Strong · 70 Moderate effect

An antioxidant play for men with fertility concerns

600 mg daily. All relevant trials used this dose for 3 months.

12 weeks. Both the primary RCT and the meta-analysis used 3-month supplementation periods.

Full breakdown

How it works

NAC is a precursor to glutathione, the body's primary internal antioxidant. In the testes, oxidative stress damages Leydig cells (which produce testosterone) and Sertoli cells (which support sperm production). By restoring glutathione levels in seminal plasma, NAC reduces oxidative damage to reproductive tissue, which can allow testosterone production to recover.¹

What the research says

A 2019 RCT in 50 infertile men found that 600 mg daily of NAC for 3 months raised testosterone alongside broad improvements in sperm count, motility, morphology, and DNA integrity.¹ However, a larger meta-analysis pooling multiple trials found no clear effect of NAC on serum testosterone specifically, while confirming the sperm quality benefits.² The testosterone finding comes from a single trial in men with confirmed fertility problems and high oxidative stress. Whether NAC moves testosterone in men without these specific issues is unknown.

Best for

Men with diagnosed fertility issues, particularly those with high oxidative stress markers. This is not a general testosterone booster. It's a targeted intervention for a specific population where oxidative damage is suppressing reproductive function.

Watch out

Interacts with nitroglycerin (can cause dangerous blood pressure drops). Can increase anticoagulant effects. GI side effects are common at higher doses.

Evidence by outcome

Boost testosterone levels Likely helps

d=0.07 Moderate effect 2 endpoints trust 70

DHEA (Dehydroepiandrosterone)

Early data

Limited · 42 Moderate effect

A direct hormone precursor that works in older adults

25 to 50 mg daily. Higher doses have been used in fertility contexts (75 mg), but for testosterone support, 50 mg is the standard studied dose.

4 to 8 weeks. DHEA is a direct precursor, so conversion to testosterone begins quickly. Most studies measured outcomes at 4 to 12 weeks.

Full breakdown

How it works

DHEA is a steroid hormone produced by the adrenal glands that serves as a direct precursor to both testosterone and estrogen. Blood levels peak in the mid-twenties and decline roughly 2% per year after that. Supplementing DHEA provides raw material that the body can convert into testosterone through enzymatic pathways, particularly in people whose natural DHEA production has declined with age.

What the research says

Two trials in older adults (total n=48) show DHEA supplementation raises both DHEA-S levels and testosterone. The effect size is moderate and the evidence is consistent but limited by small sample sizes. A crossover trial in aging men also found significant increases in DHEA-S alongside testosterone. The strongest fertility evidence comes from IVF contexts, where 75 mg DHEA improved egg retrieval and pregnancy rates in poor responders, but that's a different use case. For general testosterone support in older men, the data is promising but thin.

Best for

Men over 40 whose DHEA levels have naturally declined. This is not appropriate for younger men with normal adrenal function. DHEA is essentially providing a building block that your body already makes less of as you age.

Watch out

DHEA is a hormone, not a nutrient. It can cause acne, hair loss, and mood changes. It converts to both testosterone AND estrogen, so the net hormonal effect is unpredictable. Banned by most sports organizations (WADA, NCAA). Not recommended for anyone with hormone-sensitive cancers. Available over the counter in the US but classified as a controlled substance in some countries.

Evidence by outcome

Boost testosterone levels Early data

d=0.90 Moderate effect 2 endpoints trust 42

Magnesium

Early data

Limited · 44 Small effect

Fixes the deficiency that might be holding your T back

200 to 400 mg daily of elemental magnesium. Magnesium glycinate or citrate are better absorbed than oxide.

8 to 14 weeks in the studies that measured testosterone.

Full breakdown

How it works

Magnesium is a cofactor for over 300 enzymatic reactions, including several involved in steroid hormone synthesis. It also helps regulate SHBG (sex hormone-binding globulin), which determines how much testosterone stays free and biologically active versus bound and unavailable. The hypothesis is that magnesium deficiency (which affects roughly half the US population) constrains testosterone production, and correcting the deficiency removes that bottleneck.

What the research says

The direct testosterone evidence for magnesium is preliminary: two studies in 64 participants with a small effect size. However, the biological plausibility is strong given magnesium's role in steroidogenesis, and the high prevalence of deficiency means many men are likely leaving testosterone on the table by being low in magnesium. This is more of a 'fix the foundation' play than a testosterone booster per se.

Best for

Men who suspect they're magnesium-deficient (common if you sweat heavily, drink alcohol regularly, take certain medications, or eat a highly processed diet). If your magnesium status is already optimal, supplementation is unlikely to boost testosterone further.

Watch out

High doses (above 400 mg) can cause diarrhea, especially with magnesium oxide or citrate. Magnesium can reduce absorption of antibiotics, bisphosphonates, and thyroid medications. Separate dosing by 2 hours.

Pro tip

Get your RBC magnesium tested, not just serum magnesium. Serum levels stay normal until you're severely depleted because your body pulls magnesium from bones and tissue to maintain blood levels.

Evidence by outcome

Boost testosterone levels Early data

d=0.32 Small effect 2 endpoints trust 44

Maca (Lepidium meyenii)

Early data

Limited · 42 Small effect

Boosts libido without actually changing hormone levels

1,500 to 3,000 mg daily of gelatinized or dried root powder.

4 to 12 weeks for libido effects. Testosterone changes, if any, take longer.

Full breakdown

How it works

Maca's mechanism for sexual function remains unclear because it consistently improves libido and sexual desire without measurably changing serum testosterone, estrogen, or other reproductive hormones. The leading hypothesis involves macamides and macaenes acting on the endocannabinoid system or directly on androgen receptors, but this is speculative.²⁸

What the research says

Maca has seven testosterone-relevant endpoints across four studies (n=148), but the signal is faint. What maca does well, and consistently, is increase subjective sexual desire in men, supported by three studies showing a strong effect on self-reported libido.²⁸²⁹ A 2023 study in men over 50 found improvements in aging-male symptoms and physical performance without significant testosterone changes. If you're looking for confirmed serum testosterone increases, maca is not the answer. If you're looking for functional improvement in sex drive, the evidence is actually solid.

Best for

Men who want libido support regardless of whether their testosterone numbers change. Maca's strength is in subjective sexual function, not hormonal markers.

Watch out

Generally well tolerated, but some reports of insomnia, GI discomfort, and elevated blood pressure at higher doses. Contains compounds with theoretical MAO-inhibitory activity, so caution with antidepressants.

Pro tip

Color matters in preclinical research (red maca for prostate, black maca for sperm), but most human trials used generic yellow maca. The gelatinized form is easier on the stomach than raw.

Evidence by outcome

Boost testosterone levels Early data

d=0.30 Small effect 7 endpoints trust 42

Betaine (Trimethylglycine)

Early data

Limited · 44 Large effect

An exercise-context testosterone signal, mostly in young athletes

2,000 to 2,500 mg daily, taken with meals.

2 to 14 weeks. The shortest trial saw endocrine changes after just 14 days of supplementation.

Full breakdown

How it works

Betaine is an osmolyte and methyl donor involved in homocysteine metabolism. The testosterone link may work through improved cellular hydration in testicular tissue, enhanced methyl-group availability for steroidogenic enzymes, or cortisol reduction during intense training. The exact mechanism is not well established.²³²⁴

What the research says

Three trials with a total of 115 participants have measured testosterone alongside betaine supplementation. A 14-week study in adolescent soccer players found testosterone was preserved during a training season (when it normally drops), with a large between-group difference.²³ A 2-week crossover in teenage handball players showed higher post-exercise testosterone.²⁴ A 2023 crossover trial in adult CrossFit athletes found a small but significant testosterone increase alongside performance improvements.²⁵ The large effect sizes in the skeleton come from the adolescent studies, which have limited applicability to the general adult population. All three studies are in trained athletes during exercise interventions, so we don't know if betaine moves testosterone in sedentary adults.

Best for

Men who train regularly and want a potential edge in hormonal recovery between sessions. The evidence is thin and population-specific, but betaine is inexpensive, well-tolerated, and has separate benefits for exercise performance and homocysteine reduction.

Watch out

Can cause fishy body odor in some people at higher doses (related to trimethylamine metabolism). The serious adverse events in the safety literature (cerebral edema, lung disease) are from pharmaceutical-dose betaine used to treat homocystinuria, not supplement doses.

Evidence by outcome

Boost testosterone levels Early data

d=2.04 Large effect 3 endpoints trust 44

What doesn't work

Save your money on these

Tribulus Terrestris Not enough research

The most heavily marketed testosterone booster with the least convincing data. Two small studies totaling about 30 participants found a faint signal, but not enough to build any confidence. What tribulus actually has decent evidence for is sexual satisfaction and erectile function, which are separate outcomes from testosterone. If you're buying tribulus hoping to raise your T levels, the research doesn't support it. If you're buying it for bedroom performance, that's a different conversation.

D-Aspartic Acid Not enough research

Heavily promoted in bodybuilding circles, but we haven't deeply researched D-aspartic acid's testosterone evidence yet. The few available studies are small and contradictory, with some suggesting a temporary spike and at least one finding testosterone actually decreased. Not enough clinical research to recommend it.

Boron Not enough research

Boron is a popular ingredient in testosterone-boosting blends, but we haven't deeply researched its testosterone evidence yet. The studies that do exist are small and inconclusive, so don't expect much from products that lean on boron as a headline ingredient.

Fenugreek Not enough research

Popular in testosterone booster blends, but the data is mixed. Some trials show testosterone increases, others show none. What fenugreek may actually improve is libido and sexual function through pathways that have nothing to do with serum testosterone. If you're taking it for sex drive, fine. If you're taking it to move the number on your bloodwork, the evidence doesn't consistently back that up.

Horny Goat Weed (Epimedium) Not enough research

The name sells itself, but the testosterone evidence is entirely from animal studies. No human trials have measured serum testosterone changes with epimedium supplementation. The active compound icariin has PDE5-inhibitory activity (similar to sildenafil) which may help erectile function through a completely different mechanism than testosterone.

Synergistic stacks

Combinations that work better together

The Stress-Cortisol Stack

Ashwagandha (KSM-66) + Magnesium glycinate

Ashwagandha lowers cortisol through the HPA axis while magnesium supports the enzymatic machinery of steroid hormone synthesis. Different mechanisms, no absorption competition. If stress is driving your testosterone down, this addresses both the hormonal signal and the mineral foundation.

Ashwagandha 600 mg with breakfast, magnesium 400 mg with dinner.

The Low-T Recovery Stack

Tongkat Ali + Magnesium

Tongkat Ali directly stimulates testosterone production while magnesium corrects the deficiency that may be constraining it. The Tongkat Ali evidence is strongest in men with already-low T, which is also the population most likely to be mineral-depleted.

Tongkat Ali 200 mg with breakfast, magnesium 400 mg with dinner. Give it 8 to 12 weeks before assessing.

Buying guide

What to look for on the label

Form matters

•For Tongkat Ali, look for hot-water root extracts standardized for eurycomanone. Physta is the most-studied form. Raw root powder has not been tested in clinical trials.
•For ashwagandha, KSM-66 and Shoden are the best-studied forms. Generic root powder varies wildly in withanolide content.
•For magnesium, avoid magnesium oxide (poorly absorbed). Glycinate, citrate, and malate are better options.
•For fenugreek, extracts standardized for furostanolic saponins (like Testofen) have the testosterone-relevant data. Generic seed powder is studied for blood sugar, not hormones.

Red flags

•Any product claiming to 'boost testosterone by 300%' or similar. The largest effect seen in clinical trials (Tongkat Ali in hypogonadal men) was roughly a 30-50% increase, and that's the ceiling.
•Proprietary blends that don't disclose individual ingredient doses. If you can't verify you're getting the studied dose, you're guessing.
•'Testosterone support complex' products combining 8+ ingredients at sub-therapeutic doses. You end up with a little of everything and enough of nothing.
•Products featuring tribulus, D-aspartic acid, or boron as primary ingredients. These are marketing choices, not evidence-based choices.

Quality markers

•Third-party testing (NSF, USP, Informed Sport). Especially important for hormone-adjacent supplements where contamination with actual hormones or prohormones has been documented.
•Standardized extracts with specified active compound content (e.g., withanolides for ashwagandha, eurycomanone for Tongkat Ali).
•Companies that cite specific clinical trials on their labels or websites. If they're using a studied form, they should be able to point to the study.

The bottom line

The honest truth about testosterone supplements is that most of them don't move the needle in healthy young men with normal levels. The ones that do tend to work best in specific populations: men over 40 with declining levels, men under chronic stress, or men with nutrient deficiencies dragging their hormones down.

Tongkat Ali has the strongest direct evidence for raising serum testosterone, particularly in men whose levels have already started to decline. Ashwagandha has the deepest evidence base overall and works through a different angle, lowering cortisol to let testosterone recover. Everything else on this list has a narrower use case or weaker evidence.

If you're going to try one thing, match it to your situation. Stressed and run-down? Ashwagandha. Over 50 with confirmed low T? Tongkat Ali. Training hard and want a performance edge? Betaine is interesting but early. And if someone tries to sell you tribulus or D-aspartic acid, save your money.

Frequently asked

Common questions

Can supplements actually raise testosterone?

Yes, but modestly. The best-studied supplements raise testosterone by roughly 10 to 50 ng/dL in the populations where they work, which is meaningful if you're starting from a borderline level but won't transform someone from low-normal to high-normal. For comparison, TRT typically raises testosterone by 300+ ng/dL.⁶¹⁹ Supplements work best when something specific is suppressing your T: chronic stress (ashwagandha), age-related decline (Tongkat Ali, DHEA), or nutrient deficiency (magnesium).

I'm in my 20s with normal testosterone. Will any of these help?

Probably not in a way you'd notice. Most of the positive trials enrolled men over 40, men under chronic stress, or men with confirmed fertility issues. If your testosterone is already in the healthy range and nothing is actively suppressing it, supplements have very little room to push it higher. Your body tightly regulates testosterone through feedback loops, and healthy young men are already near their natural ceiling.

Are testosterone-boosting supplements safe?

The supplements on this list have acceptable safety profiles at the doses studied, but they're not risk-free. DHEA is an actual hormone with unpredictable downstream effects on estrogen and DHT. Ashwagandha can affect thyroid function and has rare liver injury reports. Tongkat Ali has some CYP enzyme inhibition that could affect drug metabolism. The biggest safety risk in this category is actually contamination: some testosterone booster products have been found to contain undeclared anabolic steroids or prohormones, which is why third-party testing matters.

What about zinc and vitamin D for testosterone?

Both have biological plausibility but limited direct evidence. Zinc deficiency clearly suppresses testosterone, and correcting a deficiency restores it, but supplementing above adequate intake doesn't push T higher. Vitamin D has a similar story: one trial in men with low vitamin D showed a testosterone increase after 12 months of supplementation, but it's a single study and the effect was modest. Both are worth taking if you're deficient, but neither is a testosterone booster in the way Tongkat Ali or ashwagandha are.

How long should I try a testosterone supplement before deciding if it works?

Give it at least 8 weeks, ideally 12. Get bloodwork before you start and again at 12 weeks so you have actual numbers rather than vibes. If your total testosterone hasn't moved meaningfully after 3 months at the studied dose, the supplement isn't working for you.

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Sources

Generated April 4, 2026