Tongkat Ali vs Fadogia vs Ashwagandha: Testosterone (2026)

Last reviewed: June 3, 2026 · Written by YourHealthier Science Team · Editorial Policy

Updated June 2026 · Reviewed by the YourHealthier Science Team

When comparing tongkat ali, fadogia agrestis, and ashwagandha for natural testosterone support, the deciding factor is the quality of evidence behind each. Tongkat ali has the strongest case: human clinical trials and a 2022 meta-analysis show it can raise total testosterone, likely by reducing the conversion of testosterone to estrogen and lowering cortisol. Ashwagandha supports testosterone indirectly by lowering cortisol and stress, with solid human evidence for the stress and sleep benefits themselves. Fadogia agrestis is the outlier: despite heavy social-media hype, it has no published human testosterone study, no standardized safe dose, and animal data raising testicular-safety concerns — making it the hardest to justify and the easiest to get wrong. For most men, the responsible order is to address the fundamentals first (sleep, training, body fat, stress), consider ashwagandha or tongkat ali where appropriate, and approach fadogia with real caution. Below is what each does, what the research shows, and who should be careful.

One framing matters before the details: "natural testosterone support" is not the same as treating low testosterone. If your levels are genuinely low, that is a medical issue deserving a proper workup — no supplement here substitutes for that.

Why these three get compared

Tongkat ali and fadogia agrestis are almost always discussed together because both are marketed as "natural testosterone boosters," and online communities (particularly podcast and fitness circles) popularized them as a stack. Ashwagandha gets pulled into the conversation because it is the best-known adaptogen for stress and is increasingly positioned for men's hormonal health. The problem is that grouping them implies they are interchangeable, and they are not: they differ enormously in how they work and, more importantly, in how much human evidence stands behind them.

It helps to understand the mechanisms each is proposed to use, because that explains both their appeal and their evidence gaps:

• Tongkat ali (Eurycoma longifolia): its active compound eurycomanone is thought to inhibit aromatase (the enzyme that converts testosterone to estrogen) and to help lower cortisol — two plausible, partly evidenced routes to higher available testosterone.
• Fadogia agrestis: theorized to stimulate luteinizing hormone (LH), which signals the testes to produce testosterone. This pathway is largely hypothetical in humans and rests on preclinical work.
• Ashwagandha: works upstream by reducing cortisol; since chronically elevated cortisol antagonizes testosterone, easing the stress load can indirectly support healthier testosterone, and the sleep and mood benefits help too.

Tongkat ali vs fadogia vs ashwagandha: head-to-head

	Tongkat Ali	Fadogia Agrestis	Ashwagandha
Human evidence	Yes — RCTs + 2022 meta-analysis	None published	Yes — for cortisol/stress
How it works	Aromatase inhibition, lower cortisol	LH stimulation (theorized)	Indirect — lowers cortisol
Safety profile	Well-characterized, mild effects	Unestablished; animal toxicity signals	Well-tolerated; some cautions
Typical dose	200–400 mg/day (std. ~1% eurycomanone)	No standardized human dose	~600 mg/day (KSM-66)
Best for	Direct testosterone support	Hard to recommend	Stress, sleep, indirect support

Tongkat ali: the one with human evidence

Of the two "direct testosterone boosters" in this comparison, tongkat ali is the one actually backed by human research. A 2022 systematic review and meta-analysis of randomized clinical trials, following PRISMA guidelines and drawing on PubMed, Scopus, Cochrane, and other databases, included nine studies (five RCTs in the meta-analysis) and reported a significant increase in total testosterone following Eurycoma longifolia treatment — in both healthy volunteers and men with hypogonadism (Leisegang et al., 2022). A separate six-month, double-blind, placebo-controlled RCT found that tongkat ali combined with training improved erectile function and raised total testosterone in older men with androgen deficiency (PubMed: 33541567).

On safety, tongkat ali is comparatively well-characterized. A 13-week subchronic toxicity and genotoxicity study of the powdered root found no mutagenicity or clastogenicity and an acute oral LD50 above 6 g/kg, with no adverse effects on blood, liver, or kidney markers at the doses tested (PMC3767077). Reported real-world side effects are generally mild — occasional sleep disturbance, mild increases in heart rate, and possible anxiety in sensitive individuals.

The honest caveats: not every man responds, product quality and standardization (commonly to ~1% eurycomanone) vary widely, and the strongest effects appear in older men with already-low testosterone rather than young men with normal levels. The typical researched dose is 200–400 mg/day of a standardized extract.

Transparency note: YourHealthier does not sell a tongkat ali product, so there is nothing to link here. We are covering it thoroughly because it is the best-evidenced of the two "boosters," and you deserve the full picture even where we have nothing to sell you.

Fadogia agrestis: popular, but the evidence isn't there

This is the section to read most carefully, because the gap between fadogia's popularity and its evidence is the widest in this entire comparison. Fadogia agrestis is a West African shrub that surged in popularity after being promoted in podcast and social-media circles as a testosterone booster, often stacked with tongkat ali. The reality is far less reassuring.

There is no published human trial assessing fadogia agrestis for testosterone outcomes. The entire reputation rests on a 2005 study in rats, which found higher serum testosterone in male rats given fadogia extract, but even those authors noted the mechanism was unclear. Men are not large rats, and a single rodent study is not a foundation for confident human use. Because there is no standardized human dose, anyone taking it is essentially running an uncontrolled experiment on themselves.

The safety questions are the bigger concern. Animal research on fadogia has raised signals of testicular toxicity at higher doses; the opposite of what a user hoping to support male hormonal health would want, and there is no long-term human safety data to weigh against it. In a category where a well-studied alternative (tongkat ali) exists, choosing the unstudied option with unresolved toxicity signals is difficult to justify on any rational basis.

We are not going to soften this: as a supplement decision, fadogia agrestis is built on hype rather than evidence, and the prudent stance is to avoid it until real human safety and efficacy data exist. If you are considering it anyway, that is precisely the situation where a conversation with your clinician is non-negotiable.

It is worth understanding why fadogia got so popular despite the thin evidence, because the pattern repeats across supplements. Its rise was driven almost entirely by influential podcasts and social-media figures discussing it as a testosterone tool, which created a demand wave that manufacturers rushed to fill — long before any human research existed to support the claims. This is the inverse of how evidence should drive use: the marketing and the hype arrived first, and the science never caught up. When you see a supplement that is everywhere on social media but absent from human trials, that gap itself is the warning sign. Tongkat ali, by contrast, was studied first and popularized second, which is the order you want.

Ashwagandha: the indirect, well-tolerated option

Ashwagandha takes a different route than the other two. Rather than acting directly on testosterone production, it works upstream by lowering cortisol, the body's primary stress hormone. Because chronically elevated cortisol works against testosterone, reducing that stress burden can indirectly support healthier testosterone, and the stress, sleep, and mood benefits are valuable in their own right, with human evidence behind them.

It is worth being precise: ashwagandha's strongest evidence is for stress, anxiety, and sleep, with testosterone support being more of a downstream effect than a guaranteed outcome. For men whose testosterone concerns are tangled up with high stress, poor sleep, and burnout (which is common — addressing that root cause is often more productive than chasing a direct "booster." The branded extract KSM-66 has the deepest clinical trial base, and a commonly studied dose is around 600 mg/day. KSM-66 ashwagandha also appears in evidence-informed men's-health stacks alongside cofactors like zinc and vitamin D (which support testosterone synthesis when you are deficient) and tongkat ali.

From YourHealthier: our Ashwagandha Plus (KSM-66) uses the KSM-66 extract. For the evidence and how to use it, see ashwagandha for men: testosterone, muscle & fertility, ashwagandha and cortisol, and ashwagandha dosage by goal.

The tongkat ali evidence: what meta-analyses actually found

Tongkat ali (Eurycoma longifolia) is the only one of these three compounds with a published meta-analysis specifically on testosterone outcomes. Leisegang and colleagues at the University of the Western Cape screened nine studies and included five RCTs in their 2022 quantitative synthesis. The pooled effect was statistically significant (SMD 1.352, 95% CI 0.565 to 2.138, p = 0.001), with the strongest signal in men with clinically low testosterone (PubMed).

The most cited individual trial is Henkel et al. (2014), which gave 200 mg of standardized tongkat ali extract daily to 76 men with late-onset hypogonadism for one month. Testosterone levels moved from below normal to within the reference range in 90.8% of participants, with total testosterone rising from a mean of 35.5% (PubMed). This is an encouraging finding, but the trial was small, open-label (no placebo arm), and funded by the extract manufacturer. Those limitations matter.

A more recent RCT (Antonio et al., 2024) tested 400 mg of tongkat ali daily for four weeks in exercise-trained men and women. The result: no significant differences between groups for body composition, free testosterone, cortisol, or mood. This null finding doesn't invalidate the earlier positive data, but it does suggest that effects may require longer supplementation periods, higher doses, or may be limited to men with suboptimal baseline testosterone. Healthy, active adults with normal testosterone may not see measurable changes at standard doses.

The honest summary: tongkat ali has plausible testosterone-raising effects supported by a meta-analysis, but the evidence base is small (five RCTs total), most trials are industry-funded, and the strongest results appear in men who start with low baseline levels. It is the best-studied option in this comparison, but "best-studied" among three weak evidence bases still means limited data.

Fadogia agrestis: why zero human trials is a problem

Fadogia agrestis became popular almost entirely because of mentions on the Huberman Lab podcast. The compound has exactly zero published human trials for any endpoint — testosterone, safety, dose-response, or pharmacokinetics. Everything we think we know comes from animal studies, mostly in rats.

The most cited animal study (Yakubu et al., 2005) gave rats fadogia aqueous extract at 18, 50, and 100 mg/kg/day for five days. Testosterone increased at all doses. But at higher doses, the same research group later found testicular histological changes, including increased organ weight and altered cell architecture. Whether these findings translate to humans at supplement doses is unknown, because nobody has conducted the trial. The absence of human data is not a gap that enthusiasm or influencer endorsement can fill.

Supplement companies selling fadogia are essentially asking consumers to extrapolate from a handful of rat studies, dose-convert across species (which introduces massive pharmacokinetic uncertainty), and accept the risk of a compound with documented testicular toxicity signals in animals. For a goal as serious as hormonal manipulation, this risk-benefit ratio doesn't hold up. If someone wanted to experiment with fadogia, the responsible minimum would be pre- and post-supplementation blood work (total testosterone, free testosterone, LH, FSH, liver and kidney panels) at 30 and 90 days — and a willingness to stop immediately if anything looks off.

How ashwagandha fits: the indirect testosterone path

Ashwagandha (particularly the KSM-66 root extract) approaches testosterone from a different angle. Rather than stimulating the hypothalamic-pituitary-gonadal axis directly, it works primarily through cortisol reduction. Chronically elevated cortisol suppresses testosterone production — so by lowering cortisol, ashwagandha can indirectly allow testosterone to recover toward baseline.

The strongest evidence comes from Lopresti et al. (2019), a 16-week, double-blind, placebo-controlled trial of 57 men taking 600 mg/day of KSM-66. The ashwagandha group showed 14.7% higher testosterone and 18% higher DHEA-S compared to placebo, alongside a 15% increase in salivary testosterone. Cortisol dropped by a non-significant margin, though previous Lopresti trials documented 27.9% cortisol reduction over 60 days (PubMed).

The practical implication: ashwagandha works best for men whose testosterone is being dragged down by chronic stress and elevated cortisol. If your cortisol is already normal, the testosterone-raising effect may be minimal. This is different from tongkat ali, which appears to act through Leydig cell stimulation in the testes. Both mechanisms are legitimate — they just address different upstream problems. For a complete breakdown of ashwagandha's evidence: ashwagandha for men.

Where shilajit fits

Shilajit is worth a brief mention because it appears in many men's-health and testosterone-support products, often alongside tongkat ali and ashwagandha. It is a mineral-rich resin used traditionally for energy and vitality, and some research has looked at its effects on testosterone and fertility in men. As with ashwagandha, treat it as a supportive option rather than a direct, guaranteed booster, and weigh it against the fundamentals first.

From YourHealthier: our Shilajit Adaptogen Complex is a full-spectrum resin. For what the research does and does not support, see shilajit benefits for men and whether shilajit is safe.

What actually moves testosterone first (before any supplement)

Here is the part the supplement-stack conversation tends to skip: the highest-impact levers for testosterone are not bottles. Before spending on any of these, the fundamentals do more for most men than any supplement on this page:

• Sleep. Testosterone is produced heavily during sleep; chronic sleep restriction measurably lowers it. This is often the single biggest lever.
• Resistance training and activity. Lifting and staying active support healthy testosterone and body composition.
• Body fat. Excess body fat increases aromatization of testosterone to estrogen; losing excess fat can improve levels.
• Stress management. Chronic stress keeps cortisol elevated, which works against testosterone. The exact pathway ashwagandha targets, but lifestyle handles it for free.
• Correcting deficiencies. Zinc and vitamin D are cofactors for testosterone synthesis; correcting a genuine deficiency helps, but megadosing when you are not deficient does not.

Supplements are the last 10%, not the first move. A man who sleeps poorly, carries excess fat, and is chronically stressed will get more from fixing those than from any "booster."

Who should be cautious

• Anyone considering fadogia agrestis: given the absence of human data and animal toxicity signals, this warrants particular caution and a clinician conversation.
• Men with a hormone-sensitive condition (e.g., prostate concerns): discuss any testosterone-affecting supplement with your doctor first.
• Those on medications: supplements can interact; confirm with a pharmacist.
• Anyone with symptoms of genuinely low testosterone (fatigue, low libido, mood changes): get a blood test and medical evaluation rather than self-treating with supplements.
• Younger men with normal levels: "boosters" show the least effect here; expectations should be modest.

Setting realistic expectations

Whatever you choose, calibrate your expectations to what these supplements can and cannot do, because disappointment in this category usually comes from believing the marketing rather than the data.

First, "natural testosterone support" is a modest effect at best, not a transformation. Even tongkat ali, the best-evidenced option, shows its clearest results in older men with already-low testosterone, not dramatic gains in young men with normal levels. If your testosterone is normal, do not expect a supplement to push it meaningfully higher or to feel like a different person.

Second, give any supplement a fair, defined trial and judge it honestly. Several weeks at a proper dose is reasonable; if you notice nothing, it is fair to stop rather than escalate the dose or stack more. Change one thing at a time so you can actually attribute any effect.

Third, and most important: if how you feel (energy, libido, mood, recovery) is genuinely off, that deserves a medical evaluation, not a supplement experiment. The symptoms people attribute to "low T" can have many causes, and a blood test plus a clinician is the only way to know what is actually going on. Supplements are a reasonable addition to a healthy foundation; they are a poor substitute for diagnosis.

What the social media conversation gets wrong

The testosterone supplement conversation on TikTok and YouTube follows a predictable pattern: an influencer holds up a bottle, claims it "changed my life," and shows before-and-after physique photos that could be explained by training, lighting, diet, or the passage of time. What you almost never see is bloodwork. And the reason you don't see bloodwork is that subjective "I feel better" testimonials are far more compelling to audiences than a lab report showing a 40 ng/dL increase that may or may not be clinically meaningful.

Fadogia agrestis is the most extreme example of this phenomenon. Its popularity is almost entirely traceable to a single podcast episode, not to a body of clinical research. The compound went from obscurity to bestseller status on Amazon without a single published human trial. That is an unprecedented level of consumer trust placed in an untested botanical, and the supplement industry should be embarrassed that it happened.

Tongkat ali and ashwagandha, by contrast, have earned at least a portion of their popularity through published RCTs. Neither has a perfect evidence base. But "imperfect evidence" and "zero evidence" are different categories, and treating them as equivalent does a disservice to compounds that have actually been studied.

If the social media conversation about testosterone supplements shifted from "what works for me" to "what does my bloodwork show after 12 weeks," the market would look very different. Fadogia would disappear. Tongkat ali and ashwagandha would survive — in more honest, more targeted forms. And consumers would stop spending money on compounds whose only evidence base is a rat study and a podcast recommendation.

If you decide to try one: a practical protocol

Step 1: Get baseline bloodwork. Before starting anything, get a comprehensive hormone panel: total testosterone, free testosterone, SHBG, LH, FSH, and a basic metabolic panel. Without baseline numbers, you are guessing — and supplement companies prefer that you guess, because subjective reports of feeling better are easier to generate than measurable hormonal changes.

Step 2: Fix the non-supplement factors first. Sleep deprivation drops testosterone by 10 to 15 percent (Leproult and Van Cauter, 2011, PubMed). Resistance training raises it. Excess body fat converts testosterone to estrogen via aromatase. Chronic stress elevates cortisol, which directly suppresses testosterone synthesis. If any of these factors are off, supplements will be fighting against a current that lifestyle changes could eliminate for free. For more on the cortisol-testosterone relationship: ashwagandha and cortisol.

Step 3: Choose based on your bottleneck. High stress and elevated cortisol → ashwagandha KSM-66 at 600 mg per day (dosage guide). Normal cortisol but low-normal testosterone → tongkat ali at 200 to 400 mg per day of standardized extract (minimum 2 percent eurycomanone). Neither stress nor low testosterone diagnosed → you may not need either compound.

Step 4: Retest at 8 to 12 weeks. Run the same panel. If total and free testosterone have not moved meaningfully, the supplement is not working for you — regardless of how you feel subjectively. Feeling more energetic without hormonal changes may be a placebo response or an improvement in sleep quality from ashwagandha, which is a valid outcome but not testosterone support.

What about stacking tongkat ali and ashwagandha together? No published trial has tested this combination. Mechanistically, it is plausible because they work through different pathways (direct gonadal stimulation versus cortisol reduction). Some practitioners recommend this stack for men with both high stress and suboptimal testosterone. The same monitoring protocol applies: baseline labs, 8 to 12 week retest, objective assessment. For timing: when to take ashwagandha.

One more consideration: shilajit also has preliminary testosterone data. A small RCT (Pandit et al., 2016) found 250 mg of purified shilajit twice daily increased total testosterone by 20.4 percent over 90 days in healthy men aged 45 to 55 (PubMed). The trial was small and manufacturer-funded, but shilajit addresses a different mineral pathway than either tongkat ali or ashwagandha. For the full evidence: shilajit benefits for men.

Watch: expert breakdown

Dr. Gillett and NP James O'Hara discuss the evidence, mechanisms, and safety considerations for tongkat ali and fadogia agrestis, with direct references to the published research.

Why YourHealthier

We could have written this to push what we sell, but the most useful thing we can tell you is where the evidence actually sits, including being blunt that fadogia agrestis, despite its popularity, has no human testosterone data and unresolved safety concerns. We covered tongkat ali in full even though we do not sell it, because it is the better-evidenced "booster." Where we do have a genuinely well-evidenced, well-tolerated option (KSM-66 ashwagandha for the stress-and-cortisol route) we linked it and the research behind it. And we put the unglamorous truth front and center: sleep, training, body fat, and stress move testosterone more than any supplement. That is the honest version, which we think serves you better than a bigger order.

Frequently asked questions

Watch: testosterone supplements — what the evidence actually supports

Related reading

• Ashwagandha for Men: Testosterone, Muscle & Fertility
• Ashwagandha Benefits: 7 Research-Backed Reasons
• Ashwagandha Dosage: How Much to Take by Goal
• Ashwagandha and Cortisol: The Science Behind Stress Relief
• KSM-66 vs Regular Ashwagandha
• Shilajit Benefits for Men: Testosterone, Fertility & Energy
• Shilajit Benefits: 8 Effects Ranked by Evidence
• Shilajit vs Ashwagandha: Which Adaptogen?
• Best Supplement Stacks: A No-Hype Guide
• Best Supplements for Stress: Adaptogens Ranked
• Ashwagandha Side Effects: What to Know
• Creatine for Brain Health & Focus
• Longevity Supplements: 7 That Actually Work
• Best Supplement Stack for Muscle Growth

References

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2. Henkel RR, et al. Tongkat Ali as a potential herbal supplement for physically active male and female seniors. Phytother Res. 2014;28(4):544-550. PubMed
3. Lopresti AL, Drummond PD, Smith SJ. A randomized, double-blind, placebo-controlled crossover study examining the hormonal and vitality effects of ashwagandha in aging, overweight males. Am J Mens Health. 2019;13(2):1557988319835985. PubMed
4. Yakubu MT, Akanji MA, Oladiji AT. Aphrodisiac potentials of the aqueous extract of Fadogia agrestis stem in male albino rats. Asian J Androl. 2005;7(4):399-404. PubMed
5. Antonio J, et al. The effect of Tongkat Ali supplementation on body composition in exercise-trained males and females. Appl Sci. 2024;14(11):4372.
6. Wankhede S, et al. Examining the effect of Withania somnifera supplementation on muscle strength and recovery. J Int Soc Sports Nutr. 2015;12:43. PubMed
7. Chauhan S, et al. Effect of standardized root extract of ashwagandha on well-being in adults. Cureus. 2022;14(1):e21567. PubMed

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