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Supplements for Low Testosterone: Ashwagandha, Tongkat Ali, Vitamin D, Zinc and the Booster Myths

No supplement reliably raises low testosterone. Ashwagandha raised it a little and tongkat ali by an unclear amount in trials (grade B); fenugreek barely did (grade C), and tribulus did not in men with normal levels (grade C). Vitamin D and zinc make sense only to correct a measured deficiency (grade C and D). In men with obesity, losing weight raised it (grade B). Confirmed low testosterone needs a doctor; steroids and SARMs can injure the liver and fertility.

Published How we grade evidenceEditorial policy

The short version

  • Grade B. Ashwagandha raised testosterone in men by about 57 ng/dL in a 2026 meta-analysis of placebo-controlled trials, with no change in women (Fornalik 2026).
  • Grade B. Tongkat ali raised total testosterone in a meta-analysis of 5 randomized trials, including men with low levels (Leisegang 2022).
  • Grade C. Fenugreek's rise was small and the evidence very uncertain (Yang 2026). Grade C that tribulus doesn't raise it (Vilar Neto 2025).
  • Grade C. Vitamin D did not clearly raise testosterone in men (Paez-Allendes 2026), and zinc helped only in a tiny study of men short of zinc (grade D, Prasad 1996).
  • Grade B. In men with obesity, losing weight raised testosterone compared with starting levels, most of all after weight-loss surgery (Corona 2013).
  • Anabolic steroids lower your own testosterone and sperm production, and they, SARMs and "bodybuilding" products can injure the liver (Mingxing 2025; Mohideen 2023; Stolz 2019).
OptionWhat trials foundSize of effectGrade
AshwagandhaSmall rise in menAbout 57 ng/dLB
Tongkat aliRise in 5 pooled trialsSize in everyday units unclearB
FenugreekSmall rise, very uncertainSmallC
ShilajitRise in one trial in volunteers 45 to 55Significant rise vs placeboC
Vitamin DNo clear rise0.47 nmol/L, not significantC
ZincRise only in men short of zinc8.3 to 16.0 nmol/L in 9 menD
TribulusNo robust riseNone in 8 of 10 studies, all in men with normal levelsC
D-aspartic acidNo reliable rise; 6 g a day lowered itNone or lowerC
Weight loss in men with obesity (not a supplement)Rise, bigger with more weight lost2.9 nmol/L on diet, 8.7 after surgeryB

Do testosterone boosters work?

Mostly not. Looking at 27 marketed "boosters" across 52 studies, a 2024 systematic review judged that most did not raise total testosterone; it rated tongkat ali, ashwagandha and a purified shilajit extract among the few possibly effective (Morgado 2024). For the 10 most common ingredients in 5 popular, highly rated online boosters, only 30% of 37 human studies found a rise (Balasubramanian 2019).

Does vitamin D raise testosterone?

Grade C. Not in most men. A 2026 meta-analysis found no clear change in total testosterone (11 comparisons, a difference of 0.47 nmol/L that could be zero), and it rated the certainty low (Paez-Allendes 2026). A 2019 meta-analysis of 8 studies agreed, including in subgroups split by starting vitamin D level (Hosseini Marnani 2019). Two randomized trials found no effect in healthy men, one in men whose testosterone was already low (Lerchbaum 2017; Lerchbaum 2019).

One positive trial was in overweight men with low vitamin D on a weight-loss programme. Taking 3,332 IU a day for a year raised total testosterone from 10.7 to 13.4 nmol/L in the 31 men who took it, with no change in the 23 on placebo (Pilz 2011). So test your vitamin D, and correct it if it is low, for its own sake. Upper limit for adults: 4,000 IU of vitamin D a day, because more can cause high blood calcium; take more only with blood tests or your clinician's advice (NIH ODS; check your stack).

Does zinc increase testosterone?

Grade D. Only when you are short of zinc. Nine older men with marginal zinc deficiency took zinc gluconate (about 30 mg of zinc daily) for up to 6 months, and their testosterone rose to 16.0 nmol/L, up from 8.3; there was no placebo group (Prasad 1996). In men eating enough zinc, a high-dose zinc and magnesium product did not change total or free testosterone (grade C, Koehler 2009). Upper limit for adults: 40 mg of zinc a day, because more can cause copper deficiency; take more only with blood tests or your clinician's advice (NIH ODS; check your stack).

Does ashwagandha increase testosterone?

Grade B. A little, in men. A 2026 meta-analysis of placebo-controlled trials found testosterone rose by about 57 ng/dL in men and not in women, though the trials varied and more are needed (Fornalik 2026). In one 16-week crossover trial in overweight men aged 40 to 70 with mild fatigue, an extract giving 21 mg of withanolide glycosides a day raised saliva testosterone 14.7% more than placebo, though fatigue and vigor did not differ between the groups (Lopresti 2019).

The same review found a small rise in the thyroid hormone T4, and a 73-year-old woman developed an overactive thyroid after taking ashwagandha for two years (Kamal 2022). It has also caused liver injury: in 5 cases from Iceland and the US, jaundice started 2 to 12 weeks in, and in the 4 followed up, liver tests recovered within 1 to 5 months (Björnsson 2020). Our ashwagandha guide covers stress.

Does tongkat ali increase testosterone?

Grade B. Probably, by an amount that is hard to pin down. Pooling 5 randomized trials, a 2022 meta-analysis found total testosterone went up, and the rise held in men with low testosterone (Leisegang 2022). The effect is reported only on a standardized scale, so its size in everyday units is unclear, and a 2024 review rated tongkat ali only possibly effective (Morgado 2024). In a 6-month trial in 45 men around 47 with symptoms of low testosterone, the clearest gains in erections and testosterone came in the group that combined 200 mg of tongkat ali with exercise training (Leitão 2021). Quality is a worry: in Malaysian testing, 36 of 100 tongkat ali products held more mercury than allowed (Ang 2004), and 26 of 100 in a second survey (Ang 2006).

Does fenugreek raise testosterone?

Grade C. Barely. A 2026 meta-analysis pooled 6 studies and found a small rise in total testosterone, no stable change in free testosterone, and very low certainty; none of its 13 studies had a low risk of bias, and the authors say the evidence does not support boosting claims (Yang 2026). An earlier meta-analysis of 4 trials was more positive (Mansoori 2020).

Do tribulus and D-aspartic acid work?

Grade C that tribulus doesn't raise testosterone. In a 2025 systematic review, 8 of 10 studies found no change in male hormones, but all 8 were in men whose levels were normal; the only 2 in men with low testosterone saw small rises (60 to 70 ng/dL) against their own starting levels (Vilar Neto 2025). In 21 young men, 4 weeks of tribulus left testosterone unchanged (Neychev 2005). The same review found erections improved in 3 of 5 studies at 400 to 750 mg a day, but called that evidence low (grade C). Our tribulus page rates it B for low testosterone because of those erection results; for testosterone itself, the hormone studies above are what count.

Grade C for D-aspartic acid: no reliable rise. Human results are few and inconsistent: a review found only 4 human studies, of poor quality (Roshanzamir 2017). In resistance-trained men, 3 g daily left testosterone unchanged over 28 days (Willoughby 2013), and taking 6 g daily brought both total and free testosterone down (Melville 2015).

What about shilajit, boron, magnesium and maca?

  • Shilajit, grade C. In one randomized trial in healthy volunteers aged 45 to 55, 90 days of purified shilajit, 250 mg taken twice daily, raised total and free testosterone compared with placebo (Pandit 2016). Shilajit is an Ayurvedic product, and in a US study 1 in 5 Ayurvedic medicines bought online contained lead, mercury or arsenic (Saper 2008).
  • Boron and magnesium, grade D. Each rests on one study without a placebo group in which testosterone rose: boron in 8 men for a week, where free testosterone rose (Naghii 2011), and magnesium for 4 weeks in athletes and inactive men (Cinar 2011).
  • Maca, grade C. It raised sexual desire after 8 weeks in men aged 21 to 56 without changing testosterone (Gonzales 2002).

What else raises testosterone?

Grade B for weight loss. Pooling studies of men with obesity, a meta-analysis found that total testosterone rose 2.87 nmol/L with a low-calorie diet and 8.73 nmol/L after weight-loss surgery, compared with starting levels; the more weight lost, the bigger the rise (Corona 2013). Our weight-loss guide covers what helps there.

Grade C for sleep. A review found that short or lost sleep goes with lower testosterone (Liu 2022), but two 2019 trials of short sleep in young men found little or no fall (Smith 2019). Obstructive sleep apnea (breathing stops during sleep) was linked to lower testosterone across 18 studies of 1,823 men, even after allowing for age and weight, and most clearly when it was severe (Su 2022). Loud snoring with daytime sleepiness is worth a check.

Grade B that exercise alone doesn't change it. In 11 trials (421 inactive men with normal levels in all), exercise training did not change resting testosterone; men with low levels were not tested (Potter 2021).

When is it really low testosterone, and what helps?

The Endocrine Society says to diagnose low testosterone only when you have symptoms and signs and a fasting morning blood test is clearly low, then repeat the test to confirm it and look for the cause (Bhasin 2018). When treatment is needed, the usual medicine is prescription testosterone, which your doctor prescribes and monitors. The FDA approves it only for low testosterone caused by medical conditions of the testicles, pituitary gland or brain, and says its benefit and safety for age-related low testosterone have not been established (FDA, 2015).

In a large trial in men with low testosterone and heart disease or high heart risk, major heart events were no more common on testosterone (7.0% vs 7.3%), but atrial fibrillation, acute kidney injury and blood clots in the lungs were more common (Lincoff 2023). Testosterone therapy also suppresses sperm production, so the Endocrine Society advises against it for men planning a pregnancy soon (Desai 2022; Bhasin 2018). Our sperm count guide covers fertility.

What are the risks of steroids, SARMs and "research" products?

These are drugs, not supplements, and we give no amounts. This includes anything sold as a prohormone or a "research" compound. SARMs (selective androgen receptor modulators) are unapproved muscle-building drugs.

  • Your own testosterone shuts down. In a meta-analysis of athletes and active people, anabolic steroid users had testosterone about 142 ng/dL lower, systolic and diastolic blood pressure about 12 and 8 mmHg higher, and higher LDL cholesterol and liver enzymes (Mingxing 2025). Low testosterone with symptoms can follow steroid use, depending on the dose, length and type (Rahnema 2014).
  • Infertility. Steroids, like testosterone therapy, suppress sperm production. Recovery after stopping varies with how long they were used, age and how the testicles worked before, and some men need hormone treatment or fertility help to recover (Desai 2022).
  • Liver injury. SARMs have been linked to a jaundice-type liver injury like that of steroids (Mohideen 2023). Of 44 young men with liver injury from bodybuilding supplements, 71% went to hospital, and products often held unlisted anabolic steroids (Stolz 2019). Our liver guide lists the warning signs.
  • Labels are wrong. Of 44 products sold online as SARMs, only 52% contained one, 39% contained another unapproved drug, and just 41% matched the label amount (Van Wagoner 2017). Of 92 adulterated muscle-building products the FDA flagged in 2007 to 2016, 82 held steroids or steroid-like drugs (Tucker 2018). See how to choose a quality supplement.

What we'd skip

  • Tribulus for testosterone: no change in 8 of 10 studies (Vilar Neto 2025).
  • D-aspartic acid: no rise, and a lower level at 6 g daily (Melville 2015).
  • Vitamin D in men with normal testosterone, or zinc when you already eat enough: no change (Lerchbaum 2017; Koehler 2009).
  • Anything sold as a SARM or a steroid-like "research" product: unapproved drugs, often mislabeled, linked to liver injury (Van Wagoner 2017; Mohideen 2023).

Safety and interactions

  • Ashwagandha: liver injury has been reported (Björnsson 2020). It raised the thyroid hormone T4 in trials (Fornalik 2026) and has been linked to an overactive thyroid (Kamal 2022); if you have thyroid disease or take thyroid medicine, don't start it without your clinician. If you take thyroid medicine or an antidepressant, see can I take ashwagandha with levothyroxine? and can I take ashwagandha with SSRIs?, and ask your prescriber or pharmacist.
  • Tongkat ali, shilajit and fenugreek: no studies have tested them with medicines, so ask your pharmacist if you take prescription medicines. Tongkat ali products have held mercury (Ang 2004), and Ayurvedic products bought online have held lead, mercury or arsenic (Saper 2008).
  • Tribulus: a 71-year-old man on a statin developed serious muscle breakdown (rhabdomyolysis) after taking tribulus (Huff 2024). If you take a statin, ask your prescriber first.
  • Stacks: if a blend adds zinc, vitamin D or magnesium to a multivitamin, check your stack against the upper limits.
  • Most of these trials were in adult men. Women, people who are pregnant or breastfeeding, and anyone under 18: ask a clinician.

When to see a doctor

  • Low sex drive, fewer morning erections, erection problems, breast tissue growth, hot flushes, loss of body hair or a low sperm count: get two morning blood tests through your doctor.
  • Yellow skin or eyes, dark urine, itching or pale stools while taking any supplement: stop it and get seen the same day.
  • Chest pain, a swollen painful leg or sudden breathlessness on testosterone or steroids: emergency care.
  • Symptoms after stopping steroids or SARMs: tell your doctor what you took.
  • Don't stop a prescribed medicine on your own; ask the prescriber or pharmacist.

FAQ

What is the best supplement to raise testosterone? None reliably does. Ashwagandha raised testosterone a little and tongkat ali by an unclear amount in trials in men (grade B). In men with obesity, losing weight raised it (grade B), and confirmed low testosterone needs a doctor.

Does ashwagandha increase testosterone? A little, in men. A 2026 meta-analysis found a rise of about 57 ng/dL in men and none in women (grade B). Liver injury and an overactive thyroid have been reported, so with thyroid disease or thyroid medicine, ask your clinician first.

Does vitamin D increase testosterone? Not clearly. Two meta-analyses found no clear change in men (grade C); one trial of 54 overweight men low in vitamin D found a rise. Test your level and correct it if it is low.

Does creatine increase testosterone? In 3 weeks of creatine in college rugby players, testosterone did not change, though DHT, a related hormone, rose 56% after the first week (van der Merwe 2009). Our creatine page covers its other effects.

Are SARMs safer than steroids? Not in practice. They are unapproved drugs linked to the same kind of liver injury as steroids, and in one test only about half of products sold as SARMs contained one.

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