Do Testosterone Boosters Work?

Walk down any supplement aisle or scroll through YouTube for five minutes and you'll find confident claims: take this pill, your testosterone goes up, your energy returns, your muscles come back. The market is worth billions. The ads are everywhere. At HEXIS, our physicians review testosterone panels and evaluate men with low-T symptoms weekly — this question comes up in nearly every consultation. So it's worth answering honestly, based on what 52 peer-reviewed studies actually found — not based on what the supplement companies want you to believe.

The short answer is: most don't. A handful of ingredients have real data behind them. Most of the stuff in popular products does not.

The direct answer: A 2023 systematic review of 52 studies covering 27 OTC testosterone booster compounds found that the majority of ingredients fail to raise serum testosterone. Exceptions with some supporting evidence include ashwagandha, tongkat ali, fenugreek, and shilajit — but most studies are small, short-term, or industry-funded. Tribulus terrestris, despite being one of the most-marketed ingredients, does not raise testosterone in any of the four studies that tested it. (Morgado et al., 2023)

What Does the Biggest Review of Testosterone Boosters Actually Say?

The most important piece of research on this topic is a 2023 systematic review published in the International Journal of Impotence Research (Morgado et al., 2023). The authors searched through 52 studies covering 27 distinct compounds marketed as testosterone boosters.

Their headline finding: most of these compounds simply do not raise serum total testosterone in controlled studies.

That's not a fringe opinion. That's the conclusion of a systematic review — the highest level of study design, where researchers pool results across many individual trials to find out what the evidence says when taken as a whole.

A second major review focused specifically on herbal ingredients: Smith et al. (2021), published in Advances in Nutrition, analyzed 32 randomized controlled trials across 13 different herbs. Out of those 32 trials, only 9 showed a statistically significant increase in testosterone. And only 6 of those 32 studies were rated as having a low risk of bias — meaning the research on most of these herbs is not clean enough to draw firm conclusions from.

Here's the part that matters for your wallet: these products are not FDA-approved drugs. OTC testosterone booster supplements are sold under the Dietary Supplement Health and Education Act (DSHEA) of 1994, which means manufacturers do not have to prove their product works before putting it on the shelf. The FDA does not verify efficacy or safety before sale. This is a key distinction from how TRT is prescribed and monitored under physician supervision.

That's the baseline. The ingredient-level evidence is where it gets specific.

Which Supplements Have Any Real Evidence?

Of the 27 compounds reviewed by Morgado et al. (2023), four herbal ingredients — ashwagandha, tongkat ali (Eurycoma longifolia), fenugreek seed extract, and purified shilajit — have at least some peer-reviewed evidence supporting a testosterone-raising effect. The evidence base for each is limited: trials are typically small, short (under 12 weeks), and in some cases industry-funded. Here's what the data shows for each.

Ashwagandha (Withania somnifera)

Ashwagandha root extract showed positive results in the Smith et al. (2021) systematic review of 32 herbal trials, and was confirmed by Morgado et al. (2023) as one of the compounds with benefit in healthy men. The effect appears to occur in men who are already within the normal testosterone range — representing a modest increase rather than a correction of true deficiency.

The practical question is whether a modest increase in a man who is already in normal ranges translates to any meaningful change in how he feels or performs. Study durations are typically 8–12 weeks, and sample sizes are small. The answer isn't clear yet.

Tongkat Ali (Eurycoma longifolia)

Tongkat ali has probably the most consistent positive signal in both reviews. Morgado et al. (2023) identified it among the compounds showing benefit in both men with late-onset hypogonadism and in healthy men. The mechanistic hypothesis is that it may reduce sex hormone-binding globulin (SHBG) or stimulate LH release — which could free up more testosterone.

That said: these trials are typically 4–12 weeks, often involve small samples, and some are industry-funded. A 100 ng/dL increase is real if it replicates — but if you're sitting at 250 ng/dL with genuine hypogonadism symptoms, getting to 350 ng/dL doesn't put you in an optimal range. It just moves you from one low number to another low number.

Fenugreek

Fenugreek seed extract was identified as having positive effects in the Smith et al. (2021) herbal review. There's a completed Phase 4 clinical trial (NCT03057899) that enrolled 88 men with testosterone deficiency syndrome, which adds to the evidence base.

Fenugreek appears to work partly by inhibiting aromatase — the enzyme that converts testosterone to estrogen. By blocking that conversion, less testosterone gets used up. That's a real mechanism. Whether the magnitude of the effect is clinically meaningful for men with actual low T is a different question.

Shilajit

Purified shilajit extract also appears in Morgado et al. (2023) as having evidence of benefit, specifically in men with late-onset hypogonadism. Raw shilajit — the resin form often sold online — can contain heavy metals, a documented problem in some sourced materials. Purified extract from a manufacturer with third-party testing is the only version worth considering.

Which Supplements Definitely Don't Work?

The gap between marketing and evidence is widest here.

Tribulus Terrestris

Tribulus is probably the most heavily marketed testosterone-booster ingredient in the supplement industry. It's in products that generate tens of millions of dollars in annual revenue. It has been studied four times in the Morgado et al. (2023) review.

In all four studies, tribulus terrestris did not increase testosterone.

Not "showed mixed results." Not "needs more research." Did not increase testosterone.

This ingredient is not doing what it's advertised to do. If tribulus is in your current testosterone booster, you are paying for a marketing claim without scientific support.

Vitamin D and Zinc

Both can raise testosterone — but only in men who are deficient in them. That distinction matters.

Vitamin D was covered by 10 studies in the Morgado et al. (2023) review. The finding is consistent: if a man has low vitamin D, correcting that deficiency can improve testosterone. If he's already sufficient, supplementing further doesn't move the needle.

The same logic applies to zinc — one of the 5 zinc/magnesium studies in the review. Zinc is involved in testosterone production, and zinc deficiency genuinely suppresses testosterone. But if your zinc levels are already normal, more zinc doesn't make more testosterone.

Getting your vitamin D and zinc tested is worthwhile. Correcting a real deficiency with appropriate doses makes sense. Spending $60/month on a high-dose "zinc booster" when your levels are already fine is not.

D-Aspartic Acid

D-aspartic acid (DAA) was one of the compounds reviewed in Morgado et al. (2023). The results were inconsistent across 2 studies — one showed an increase, one didn't. DAA stimulates LH release in theory, but the evidence base is thin enough that it's difficult to draw firm conclusions. It's a story this whole category keeps telling: promising mechanism, one positive trial, then nothing replicates cleanly.

What's Wrong With Most Testosterone Booster Products?

Most OTC testosterone booster products are formulated in ways that make the ingredient-level evidence irrelevant — even when a specific herb has supporting data. The primary problem is proprietary blends, and the secondary problem is contamination risk.

Most popular testosterone boosters use proprietary blends — a single listing that says "Testosterone Support Blend: 1200mg" with a dozen ingredients listed underneath but no indication of how much of each ingredient is in the formula. This matters because most of the ingredients with supporting evidence were tested at specific doses. If a study showed fenugreek working at 500mg/day and your product contains 50mg buried in a blend, that evidence doesn't transfer.

There's also a contamination concern specific to shilajit in raw resin form — heavy metals are a documented issue in some sourced materials. And more broadly, the supplement industry operates without mandatory pre-market testing, so what's on the label isn't always what's in the capsule.

If you're using any supplement, third-party testing verification (NSF Certified for Sport or USP Verified) is the minimum bar.

What Are the Actual Symptoms of Low Testosterone?

"Low energy" or "I want to be 22 again" is not the same as clinically low testosterone. Genuine hypogonadism produces a specific cluster of symptoms.

Testosterone production naturally declines with age — research on testosterone's role across the lifespan shows the decline is gradual but meaningful, with effects on muscle mass, bone density, and energy regulation becoming more pronounced over time (Barone et al., 2022). That age-related decline is different from true hypogonadism, which is a clinical diagnosis based on blood work, not just feeling tired.

The symptoms of actual low T include:

• Persistent fatigue that doesn't respond to normal rest
• Low libido — meaningful, sustained reduction, not just a bad week
• Loss of muscle mass despite training
• Increased body fat, particularly central (belly) fat
• Difficulty concentrating
• Depression or mood changes
• Reduced morning erections or erectile dysfunction

These symptoms overlap with a lot of other conditions. That's precisely why the only reliable way to know if testosterone is genuinely low is a blood test — and why the timing of that test matters. Serum total testosterone should be measured in the morning, when levels are naturally at their peak, on at least two separate occasions (Livingston et al., 2017). A single afternoon reading can produce a false-low result.

The threshold for hypogonadism varies slightly by lab but is generally below 300 ng/dL total testosterone. Understanding the symptoms of low testosterone and what they actually indicate is the first step toward getting the right evaluation.

How Is Low Testosterone Properly Diagnosed?

Testosterone itself is only part of the picture — and that's why proper diagnosis matters. When you check testosterone levels, the first result tells you total testosterone — but total testosterone includes testosterone bound to proteins like SHBG, which can't actually be used by your cells. Free testosterone, the fraction that is available for use, can be low even when total testosterone appears borderline-normal (Livingston et al., 2017).

A complete evaluation looks at:

• Total testosterone (morning draw, twice)
• Free testosterone (since binding globulin levels affect how much is usable)
• LH and FSH (to distinguish primary hypogonadism from secondary, which involves the pituitary)
• Thyroid function, complete blood count, vitamin D, and zinc status

That combination of numbers tells you whether low T is real, whether it's coming from the testes or the pituitary, and what treatment actually makes sense for your specific situation. The European Academy of Andrology guidelines are clear that confirmed hypogonadism warrants physician evaluation and individualized treatment planning (Corona et al., 2020).

How Does OTC Compare to Prescription TRT?

Prescription testosterone replacement therapy (TRT) and OTC testosterone booster supplements are not comparable interventions — they differ in regulatory status, mechanism, dosing precision, and magnitude of effect.

TRT is FDA-approved for diagnosed hypogonadism. It comes in several clinically validated delivery forms — intramuscular injection, transdermal gel, topical solution, subcutaneous pellets — each with different pharmacokinetics and patient preferences (Barbonetti et al., 2020). The goal is to restore testosterone to the mid-to-upper normal range with calibrated, physician-monitored dosing.

OTC supplements are dietary products sold without proof of efficacy. For a full breakdown of how prescription TRT is prescribed and monitored, see our guide on testosterone replacement therapy for men.

The TRAVERSE trial, one of the largest RCTs of prescription TRT ever conducted, enrolled men with confirmed hypogonadism and demonstrated improvements in sexual function and hypogonadal symptoms with prescription testosterone (Pencina et al., 2024). The prostate safety data from that same trial showed that TRT did not increase the risk of high-grade prostate cancer (Bhasin et al., 2023). Separately, TRAVERSE data showed that prescription TRT significantly improved depressive symptoms in men with hypogonadism who had depressive syndromes at baseline (Bhasin et al., 2024).

Sexual function is one of the primary drivers men seek testosterone evaluation. Research on TRT specifically for sexual symptoms — including low libido and erectile dysfunction — shows clinically meaningful improvements in men who have confirmed low T (Rastrelli et al., 2019). Supplements, even the ones with positive trial data, have not been studied for sexual symptom endpoints with anywhere near the rigor of these prescription TRT trials.

This is a different category of evidence from anything in the OTC supplement space.

An OTC supplement might move your testosterone from 280 ng/dL to 330 ng/dL — if it works at all, and if you're using one of the few ingredients with actual evidence. Prescription TRT, when appropriately dosed, restores testosterone to the mid-to-upper normal range. That is a fundamentally different intervention.

For men weighing whether they need prescription therapy versus lifestyle and supplement approaches, understanding who TRT is actually for requires a real diagnosis, not a symptom checklist (Tsametis & Isidori, 2018). The TRAVERSE data is about prescription TRT — it does not validate OTC supplements, and conflating the two would be a misreading of what those trials actually tested.

When Should You See a Doctor Instead of Trying Supplements?

Men with persistent low-testosterone symptoms — fatigue, low libido, muscle loss, mood changes lasting more than a few weeks — should get a blood test, not another supplement. Delaying a proper evaluation by cycling through OTC products costs real time in a condition where treatment lag has documented consequences for bone density and muscle mass.

Dr. Rena Malik, MD — a board-certified urologist and pelvic surgeon who covers evidence-based men's health in her clinical education content — has consistently emphasized that creatine, beta-alanine, and most marketed OTC testosterone boosters do not convincingly raise testosterone. Her position: men experiencing real symptoms should not delay proper evaluation by cycling through supplements first.

There's also a cost-of-delay issue. If your testosterone is genuinely in the low-hypogonadal range, a year spent trying supplements before getting properly tested and treated is a year of unnecessary symptoms — and potential ongoing loss of bone density and muscle mass. The European Academy of Andrology guidelines are clear that confirmed hypogonadism warrants physician evaluation and treatment, not a supplement trial (Corona et al., 2020).

The Bottom Line on Testosterone Boosters

The OTC testosterone booster industry is built on a real problem — low T is genuinely underdiagnosed and undersupported in medicine — but the products often don't solve it.

Some ingredients have data worth taking seriously. Ashwagandha, tongkat ali, fenugreek, and shilajit (purified, third-party tested) have signals that aren't completely dismissed by the research. Vitamin D and zinc matter if you're deficient. Tribulus does not raise testosterone, period.

But even for the better options, the honest framing is: these ingredients may produce a modest increase in testosterone at the margins for men who are already in normal-to-low ranges. They are not a substitute for physician-supervised evaluation if you have real symptoms.

If you want to understand your own numbers and get a full picture of what's happening with your hormones, HEXIS starts with labs — not with a protocol built on guesswork. A consultation with a HEXIS provider means reviewing your actual testosterone panel, not estimating based on symptoms alone. That's how you find out whether supplements, lifestyle changes, or prescription TRT is actually appropriate for your situation.

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Frequently Asked Questions

Do testosterone booster supplements actually work?

Most don't. A 2023 systematic review of 52 studies covering 27 OTC compounds found the majority fail to raise serum testosterone (Morgado et al., 2023). A small number of ingredients — ashwagandha, tongkat ali, fenugreek, and purified shilajit — have some supporting evidence, but most studies are short-term and small. Tribulus terrestris, widely marketed, does not raise testosterone in any of the four studies that tested it.

Does tribulus terrestris boost testosterone?

No. Despite being one of the most-marketed testosterone booster ingredients, tribulus terrestris failed to raise serum testosterone in all four studies reviewed by Morgado et al. (2023). The marketing claims for this ingredient are not supported by the controlled research.

What's the difference between OTC testosterone boosters and TRT?

OTC testosterone boosters are dietary supplements not reviewed by the FDA for efficacy. Prescription TRT is an FDA-approved medical treatment for confirmed hypogonadism, administered and dosed by a physician based on lab results (Barbonetti et al., 2020). The evidence base, the magnitude of effect, and the level of medical oversight are entirely different categories.

Should I take testosterone supplements before seeing a doctor?

Not as a substitute for evaluation. If you have persistent symptoms of low testosterone — fatigue, low libido, loss of muscle mass — the right first step is a blood test, not a supplement cycle. Some supplements may be worth discussing with your provider, but they don't replace proper diagnosis (Livingston et al., 2017).

Do zinc and vitamin D boost testosterone?

Only if you're deficient. Zinc and vitamin D are involved in testosterone production, and correcting a true deficiency can improve levels. If your levels are already adequate, additional supplementation does not raise testosterone further. Both are worth testing before supplementing (Morgado et al., 2023).

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