A handful of supplements have shown the ability to increase testosterone in clinical studies, but the effects are modest and often depend on whether you’re deficient in a specific nutrient to begin with. Zinc, magnesium, ashwagandha, fenugreek, D-aspartic acid, and boron are the most studied options. None of them will transform low testosterone into high testosterone on their own, but for men with nutritional gaps or borderline levels, certain supplements can produce a measurable difference.
Zinc and Magnesium: Filling Nutritional Gaps
Zinc and magnesium are the two minerals most directly tied to testosterone production, and deficiency in either one can drag levels down. A study from the American Society of Exercise Physiologists tested a combination of 30 mg zinc, 450 mg magnesium, and 10.5 mg vitamin B6 (sold as ZMA) in football players over an eight-week training period. The ZMA group saw total testosterone rise from about 568 to 752 ng/mL, while the placebo group actually declined slightly. Free testosterone jumped from 132 to 176 pg/mL in the supplement group.
Those are striking numbers, but context matters. The athletes in this study were training intensely, which depletes both zinc and magnesium through sweat and muscle repair. If you’re already getting enough of these minerals through your diet (red meat, shellfish, nuts, seeds, leafy greens), supplementing more won’t push testosterone higher. The benefit comes from correcting a shortfall, not from megadosing. Zinc in particular has a ceiling effect: once your body has enough, extra zinc won’t keep raising testosterone and can actually cause nausea or interfere with copper absorption.
Ashwagandha
Ashwagandha is one of the better-supported herbal options for testosterone. It works primarily by lowering cortisol, the stress hormone that competes with testosterone production. Multiple trials have shown increases in both total and free testosterone in men taking 300 to 600 mg of a root extract daily, with effects typically appearing after eight weeks of consistent use. The increases tend to be more pronounced in men who are stressed, sleep-deprived, or physically overtrained.
There are real safety considerations with ashwagandha, though. The National Center for Complementary and Integrative Health warns against using it if you have thyroid disorders or autoimmune conditions. It can interact with medications for diabetes, high blood pressure, seizures, and thyroid hormones, as well as immunosuppressants and sedatives. People with hormone-sensitive prostate cancer should avoid it entirely because of its testosterone-raising potential.
D-Aspartic Acid: A Short-Lived Boost
D-aspartic acid (DAA) is an amino acid that triggers the release of luteinizing hormone, the signal from your brain that tells your testes to produce testosterone. In one well-known study, 3 grams per day for 12 days increased testosterone by 42% and luteinizing hormone by 33%. Levels stayed elevated even three days after stopping supplementation.
The catch is that longer studies paint a less impressive picture. When researchers have extended DAA supplementation beyond two to three weeks, testosterone levels tend to drift back toward baseline. Your body appears to adjust to the stimulus. This makes DAA more of a short-term tool than a long-term strategy, and the dramatic percentage increases from that initial 12-day study haven’t been consistently replicated in longer or larger trials.
Fenugreek
Fenugreek seed extracts contain compounds called furostanolic saponins that appear to influence testosterone by inhibiting enzymes that convert it into estrogen. A 12-week study of 50 men aged 35 to 65 used 500 mg per day of a standardized extract enriched to 20% protodioscin (the active compound) and found improvements in both free and total testosterone, along with self-reported improvements in libido and mood.
The practical effect of fenugreek is generally mild. You’re unlikely to notice a dramatic physical change, but some men report better energy and sex drive within a few weeks. The extract can cause a maple syrup-like smell in sweat and urine, which is harmless but noticeable. Fenugreek also has blood sugar-lowering effects, so if you’re on diabetes medication, that interaction is worth being aware of.
Boron: A Lesser-Known Trace Mineral
Boron gets less attention than zinc or magnesium, but a small body of research suggests it can raise free testosterone by lowering sex hormone-binding globulin (SHBG), the protein that binds to testosterone and makes it unavailable for your body to use. In one study, 10 mg of boron daily produced a significant drop in SHBG within just six hours of the first dose, and free testosterone increased after one week of daily supplementation.
Most people get only 1 to 3 mg of boron per day through food (raisins, almonds, avocados), so a 6 to 10 mg supplement represents a meaningful increase. The research base is still thin compared to zinc or ashwagandha, but the early data is consistent enough that boron shows up in many well-formulated testosterone support products.
Vitamin D: Not What You’d Expect
Vitamin D is frequently marketed as a testosterone booster, and observational studies do show a clear correlation: men with higher vitamin D levels tend to have higher testosterone. But when researchers have tested vitamin D supplementation in randomized controlled trials, the results have been consistently disappointing. A structured review in the journal Clinical Therapeutics concluded there is “no sound evidence for the use of vitamin D supplementation as a testosterone adjuvant.”
This doesn’t mean vitamin D is worthless. Severe deficiency affects many body systems and correcting it supports overall health. But if you’re specifically trying to raise testosterone, vitamin D supplements alone are unlikely to move the needle in a clinically meaningful way.
Tribulus Terrestris: Popular but Unproven
Tribulus terrestris is one of the most heavily marketed testosterone-boosting herbs, but human evidence is weak. While some studies suggest modest effects on sexual function, clinical trials looking specifically at testosterone levels in men have produced mixed results. The Department of Defense’s Operation Supplement Safety program notes that findings on tribulus and testosterone are inconsistent. If you see it as the lead ingredient in a “T-booster” blend, that’s a red flag about how evidence-based the product is.
Safety Risks With Testosterone Supplements
The biggest danger in the testosterone supplement market isn’t the well-studied individual ingredients. It’s the proprietary blends and bodybuilding products that contain undisclosed or contaminated compounds. Research from Michigan Medicine found that many bodybuilding supplements linked to liver injury contained hidden anabolic steroids. These products can cause severe liver inflammation that takes months to resolve. In one case series, six patients taking a weight-loss supplement containing green tea extract developed significant liver damage, with four becoming severely jaundiced.
Stick to single-ingredient supplements from brands that provide third-party testing (look for NSF Certified for Sport or Informed Sport labels). Avoid products with vague “proprietary blends” that don’t disclose individual ingredient amounts. If a supplement promises results that sound like a steroid, it may literally contain one.
What Actually Moves the Needle
Supplements work best as gap-fillers, not primary interventions. A zinc or magnesium supplement can help if your diet is lacking, and ashwagandha may offer a modest boost if stress or poor sleep is suppressing your levels. But the lifestyle factors that influence testosterone are far more powerful: resistance training (especially compound lifts like squats and deadlifts), seven or more hours of sleep per night, maintaining a healthy body fat percentage, and managing chronic stress. Losing excess body fat alone can raise testosterone significantly, because fat tissue converts testosterone into estrogen.
If your testosterone is genuinely low (below about 300 ng/dL on a morning blood test), supplements are unlikely to bring you into a normal range. That’s the territory where medical treatment becomes relevant. For men in the low-normal range who want a modest edge, a targeted supplement combined with consistent training and sleep habits is a reasonable approach.