El tongkat ali es un extracto de raíz que se vende para la testosterona, la libido y el estrés, y pequeños ensayos en humanos respaldan una versión acotada de esa afirmación. En un análisis conjunto de cinco ensayos aleatorizados, elevó la testosterona total en hombres. El efecto fue más claro en hombres mayores o en hombres cuya testosterona era baja al inicio, y prácticamente nulo en hombres más jóvenes cuyos niveles ya eran normales.
Un ensayo controlado con placebo distinto halló que el cortisol descendía. La evidencia es escasa: los ensayos son pequeños y cortos, varios se basan en un único extracto de marca, y algunos están financiados por su fabricante.
Findings & Outcomes
What It Is
Healers across Malaysia, Indonesia, and neighboring countries have used the bitter root of Eurycoma longifolia for generations as a tonic for energy, stamina, and male vitality. The plant is a tall rainforest shrub. Longjack and Malaysian ginseng name the same root.
The active compounds are a family of bitter molecules called quassinoids, best known among them eurycomanone, alongside related steroid-like compounds. Water extraction of the root concentrates them; raw powder does not. Modern supplements sell it mainly for testosterone and libido, often stacked with a second herb, Fadogia agrestis.
What the Trials Show
Pooled across five randomized trials, tongkat ali raised total testosterone in men. Older men and men with low baseline testosterone gained the most; younger men already in the normal range gained little to nothing. A separate placebo-controlled trial in moderately stressed adults measured cortisol directly and found it fell over four weeks.
The libido, erectile-function, and strength signals each rest on one or two small trials.
Fadogia agrestis, the herb tongkat ali is usually stacked with, has no human trials at all.
The evidence leans on one preparation. Several of the single trials used the same branded water extract, Physta, and two were funded by its maker. The meta-analysis that pooled them declared no such funding.
The longest trials ran about twelve weeks, so nothing is known past that. Among supplements marketed for testosterone, few show any randomized human signal; tongkat ali is one that does, though still short of proof.
The Research & Studies
Everything here is based on the research we have collected and checked, sorted into groups and ordered with the strongest evidence first. Click any claim to open the studies behind it.
Progress Markers
Total testosterone rose in men across five trials (SMD 1.35), most in those low to start
Across the randomized trials pooled together, tongkat ali raised testosterone in men, and the increase was clearest in older men and men whose testosterone was low to start with.
A meta-analysis of five randomized trials found tongkat ali raised serum total testosterone in men (standardized mean difference 1.35, 95% CI 0.57 to 2.14), with the effect confirmed in the hypogonadal subgroup. A 12-week placebo-controlled trial in 105 men aged 50 to 70 with testosterone below 300 ng/dL saw total testosterone rise on 200 mg a day of a standardized extract. Measured in: Men, pooled from randomized trials of healthy and hypogonadal volunteers; the largest single RCT enrolled 105 men aged 50 to 70 with low testosterone.. The trials are small and heterogeneous, several are built around a single branded water extract (Physta) and some were funded by its manufacturer, and the effect is larger in hypogonadal or older men than in men already in the normal range. Follow-up was 4 to 12 weeks.
Who this may not transfer to:The pooled testosterone trials were in men, and the outcome is male serum testosterone in the context of hypogonadism and aging, so the finding does not transfer to women.
The studies · 3
Leisegang et al. 2022, Medicina · Medicina (Kaunas) 2022;58(8):1047
Chinnappan et al. 2021, Food Nutr Res · Food Nutr Res 2021;65:5647
Tambi et al. 2012, Andrologia · Andrologia 2012;44 Suppl 1:226-30
Counts once: this finding and 2 others here come from the same source, so they are one body of evidence, not separate confirmations.
Across 52 studies of testosterone boosters, most did nothing; tongkat was one of the few with a signal
When researchers reviewed the whole shelf of testosterone-booster supplements, most did nothing measurable; tongkat ali was one of the few with any measurable signal.
A systematic review of 52 studies covering 27 marketed testosterone-boosting ingredients found that most did not measurably raise total testosterone. Eurycoma longifolia was among the few judged possibly effective, for men with late-onset hypogonadism and for healthy men. Measured in: Systematic review across male athletes, men with late-onset hypogonadism, infertile men and healthy men.. The review's own verdict for tongkat ali is possibly effective, not established, and rests on the same small trial base graded elsewhere on this page; the label distinguishes it from ineffective ingredients, not proving a large effect.
Who this may not transfer to:The review's outcome was serum total testosterone in male populations, so it does not speak to effects in women.
The study · 1
Morgado et al. 2024, Int J Impot Res · Int J Impot Res 2024;36(4):348-364
Anxiety And Stress
Cortisol fell about 16% and testosterone rose about 37% over four weeks under stress
In stressed adults, four weeks of a standardized extract lowered the stress hormone cortisol, raised testosterone slightly, and improved several mood scores.
In 63 moderately stressed adults, four weeks of a standardized hot-water root extract lowered salivary cortisol by about 16% and raised testosterone status by about 37%, with reductions in tension (-11%), anger (-12%) and confusion (-15%) on a standardized mood scale. Measured in: 63 adults (32 men and 31 women) screened for moderate stress, placebo-controlled.. A single small 4-week trial in a self-selected moderately stressed group, using one standardized extract; the mood measures are self-reported scales and the result has not been replicated at this size.
Who this may not transfer to:The trial enrolled both men (32) and women (31) and reported the pooled effect across the group.
The study · 1
Talbott et al. 2013, J Int Soc Sports Nutr · J Int Soc Sports Nutr 2013;10(1):28
Sexual Function
Erectile-function scores improved over 6 months in aging men on 200 mg a day
Over six months, a daily standardized dose improved erectile-function scores in aging men, most so when it was paired with regular exercise.
In a 6-month randomized trial in 45 men (mean age 47) with androgen deficiency of aging, 200 mg a day of a standardized extract improved erectile-function scores and total testosterone, with the largest improvement in the group that combined the extract with concurrent exercise training. Measured in: 45 men, mean age about 47, with androgen deficiency of aging (ADAM), randomized across four arms.. The trial had no arm testing the extract alone against training alone, so its independent contribution cannot be cleanly separated from the exercise, and the sample was small.
Who this may not transfer to:Erectile function is a male-specific outcome measured only in men, so it does not transfer to women.
The study · 1
Leitao et al. 2021, Maturitas · Maturitas 2021;145:78-85
Energy And Fatigue
La fatiga y los síntomas de envejecimiento masculino bajaron a lo largo de 12 semanas con 200 mg al día
Hombres mayores con testosterona baja reportaron menos fatiga y menos síntomas relacionados con el envejecimiento con una dosis estandarizada a lo largo de 12 semanas.
En el ensayo controlado con placebo de 12 semanas en 105 hombres envejecidos con testosterona baja, 200 mg al día de un extracto estandarizado redujeron las puntuaciones de la Escala de Gravedad de la Fatiga y de Síntomas del Envejecimiento Masculino en comparación con placebo, con la reducción apareciendo dentro de dos semanas. Measured in: 105 men aged 50 to 70 with testosterone below 300 ng/dL, placebo-controlled.. Un único ensayo financiado por un fabricante usando cuestionarios de síntomas; los resultados son escalas autoinformadas y el resultado no se ha replicado de forma independiente con este tamaño.
Who this may not transfer to:Measured only in aging men with low testosterone; the fatigue effect has not been tested in women or in men with normal levels.
The study · 1
Chinnappan et al. 2021, Food Nutr Res · Food Nutr Res 2021;65:5647
Counts once: this finding and 2 others here come from the same source, so they are one body of evidence, not separate confirmations.
Muscle And Strength
Handgrip strength rose in active seniors on 400 mg a day for five weeks
A couple of small studies found modest gains in muscle strength in older adults taking a standardized extract, though this was a secondary result and not the main question.
Muscle strength rose as a secondary endpoint in the 12-week placebo-controlled trial of a standardized extract in aging men, and an uncontrolled pilot in 25 physically active seniors (13 men, 12 women) taking 400 mg a day for five weeks reported increased handgrip force alongside higher testosterone. Measured in: Aging men in a 12-week RCT (strength as a secondary endpoint) and 25 physically active seniors aged 57 to 72 in an uncontrolled 5-week pilot.. Strength was a secondary endpoint in one trial and the supporting pilot had no control group, so the ergogenic signal is thin and not yet tested as a primary outcome.
Who this may not transfer to:The pilot included both men and women aged 57 to 72 and reported strength gains in both, while the RCT strength endpoint was in men.
The studies · 2
Chinnappan et al. 2021, Food Nutr Res · Food Nutr Res 2021;65:5647
Henkel et al. 2014, Phytother Res · Phytother Res 2014;28(4):544-50
Counts once: this finding and 2 others here come from the same source, so they are one body of evidence, not separate confirmations.
How it works
Fadogia agrestis raised testosterone in rats at 18 to 100 mg/kg, never tested in people
The testosterone reputation of Fadogia agrestis comes entirely from rat studies, where it raised testosterone and mating behavior. It has never been tested in people.
In male rats, an aqueous stem extract of Fadogia agrestis at 18, 50 and 100 mg/kg raised serum testosterone in a dose-related way and increased mounting and intromission frequency over five days. No human trial of Fadogia agrestis has been published. Measured in: Male albino rats; no human studies exist.. This is a rodent finding only, at doses and by a route that do not translate to human use, and the same research line reported testicular harm at sustained higher doses.
Who this may not transfer to:Measured only in male rats; no human trial of Fadogia agrestis has been done, so the finding does not transfer to people.
The study · 1
Yakubu et al. 2005, Asian J Androl · Asian J Androl 2005;7(4):399-404
How It Works
Anatomy of the Practice
1In the stress and hormone system
Tongkat ali acts on the hormonal stress axis, easing cortisol output while supporting the body's own testosterone. The testosterone-to-cortisol ratio roughly tracks whether the body is building or breaking down tissue. This pairing is the best-measured of the herb's effects in people.
2On free testosterone
Some testosterone in the blood is bound to a carrier protein, SHBG, and is not available to tissues. Part of the herb's action is a rise in the unbound fraction; one trial in older adults saw free testosterone rise as that carrier protein fell. The shift is modest and measured in small groups.
3Who it moves most
Any hormonal shift is larger in men who started with low testosterone and smaller in men already in the normal range, where there is less to change. The effect works through the body's own production, so it depends on a system that can still respond.
The quassinoids in the root, eurycomanone chief among them, raise testosterone in laboratory and animal studies. They act on the signaling that drives testosterone production in the testes, and on the enzyme that converts testosterone into estrogen. That matches the human trials. It also fits the smaller effect seen in a man whose levels are already normal.
Tongkat ali raises the body's own testosterone output by a small amount. Testosterone therapy replaces the hormone from outside and lifts it into a range a clinician targets, with monitoring for fertility and blood thickness.
Choosing and Using It
Ways to Do It
The levers that raise testosterone and steady stress hormones are mostly free, and they are the first thing to try for any man. A standardized extract is a low-cost addition on top of those basics, most useful for older men or men with confirmed low testosterone.
Losing excess weight, sleeping enough, treating sleep apnea, resistance training, and drinking less alcohol each raise testosterone or lower the stress hormones that suppress it. Together they move it more than any capsule, and they carry the strongest evidence. A supplement added on top of neglected basics does the smaller share of the work.
The human trials used a standardized water extract of the root, most often 200 mg a day, ranging from about 100 to 400 mg, taken for four to twelve weeks. The trials used a water extract; raw-root powder and undefined blends are a different material. This is the studied range for fatigue, stress, or blood-confirmed low testosterone. Check your levels with a clinician before and after.
Independent testing catches contamination and confirms the capsule holds a defined extract. Look for a mark such as NSF or Informed Choice, or a published heavy-metal certificate of analysis. Standardization also varies widely between brands, so a product that names what it standardizes to is the closest match to the research.
Set one dose for eight to twelve weeks, tracking a single symptom or lab value. Then stop and see what holds without it. That gives a clearer read than an open-ended habit while the picture past twelve weeks is still thin.
Supplements often pair tongkat ali with Fadogia agrestis on the same testosterone claim, though Fadogia has no human trials behind it. That leaves tongkat ali as the only half of the stack tested in people. Its animal safety signal is set out in the cautions.
Go Deeper
- Testosterone therapy: how confirmed low testosterone is actually diagnosed and treated.
- Ashwagandha: another root taken for stress and testosterone, with the same pattern of small, often industry-funded trials.
The Chinese Medicine View
Tongkat ali grows in Southeast Asia, in the traditional medicine of Malaysia and Indonesia, not China. The classical Chinese texts never listed it, so it has no assigned channel, temperature, or flavor.
Its use still lines up with a familiar Chinese category: the warming Yang tonics. Healers have long given bitter, warming roots to people who are cold, depleted, tired, and low in drive, the Kidney Yang picture of warmth, stamina, and reproductive vitality. A root taken for centuries to restore energy and male vigor sits squarely in that group.
The modern trials point at the same men: older, depleted, or low in testosterone. Chinese medicine had no concept of testosterone, so the parallel holds only for who and what is treated: low drive, fatigue, waning vigor.
A Yang tonic was never meant for everyone. It suits the cold and depleted person and burdens the one who already runs hot or dry. Yin-deficiency signs (night sweats, a flushed face, restlessness, hot palms) mark someone a warming herb would push further toward heat. It is an interesting parallel that the measured benefit also falls mostly to men who were depleted to start and fades in men who began in better shape, but the tradition never measured testosterone, so the parallel is offered here as a lens, not as the old framework being confirmed.
Cautions For This Practice
Extra restraintEverything to be aware of is here, in one place. This practice suits most healthy people; a few situations call for real care.
Mercurio por encima del límite en el 36 % de los productos de tongkat ali probados
In a survey of 100 tongkat ali herbal preparations from the Malaysian market, 36% contained mercury from 0.52 to 5.30 ppm, above the permitted limit for traditional medicines, with contamination varying batch to batch. Este es un problema de calidad del mercado, no una propiedad de la hierba, medido en productos malasios; argumenta a favor de extractos estandarizados y probados de forma independiente, no polvos sin verificar.Ang et al. 2004, Int J Toxicol
Fadogia agrestis harmed rat testicular function over 28 days of dosing
In male rats given an aqueous Fadogia agrestis stem extract daily for 28 days at 18, 50 and 100 mg/kg, testicular function indices shifted in a direction the authors described as adverse to testicular function, with recovery mainly at the lowest dose. Related work reported liver and kidney changes. This is an animal toxicity signal at sustained higher doses; human safety has not been studied, so the size and threshold of any risk in people is unknown, not reassuringly absent.Yakubu et al. 2008, J EthnopharmacolYakubu et al. 2009, Hum Exp Toxicol
Fadogia agrestis, the common stack partner, has an animal testicular-toxicity signal and no human data
Fadogia agrestis, the herb sold alongside tongkat ali on the same testosterone claim, has never been tested in a human trial. Its reputation rests on rat studies. A low-dose stem extract raised testosterone and mating behavior. At higher daily doses over four weeks, it damaged testicular tissue, the researchers called the change adverse, with recovery mainly at the lowest dose. Related animal work reported liver and kidney changes too. There is no human safety data on Fadogia agrestis.
Heavy-metal contamination in some products
Market surveys have found mercury above the permitted limit in about a third of tongkat ali products, with levels varying by batch and source. This is a product-quality problem tied to how a given batch is made, so independent heavy-metal testing on the specific product is the check that matters.
Hormone-sensitive conditions and fertility treatment
Tongkat ali can shift testosterone and related hormones, so anyone with a hormone-sensitive condition, being treated for one, or undergoing fertility treatment should raise it with their clinician before starting. How much these hormones move in these groups has not been measured.
Existing medication and medical conditions
The human trials were short and run mostly in otherwise healthy men. Effects alongside long-term medication, or in significant heart, liver, or kidney disease, are not well characterized. On regular medication or a chronic condition, tell your prescribing doctor before starting, and keep to the doses and standardized extracts the trials used.
Do not let it delay a low-testosterone diagnosis
Confirmed low testosterone (hypogonadism) is diagnosed on morning blood tests, and its treatment is a clinician's call. Using tongkat ali to self-treat symptoms of possible low testosterone can delay that diagnosis. If symptoms persist (low drive, fatigue, poor erections) get a morning blood test before relying on a capsule.
Pregnancy, breastfeeding, and use by women
Most of the human research is in men. Tongkat ali has not been studied for safety in pregnancy or breastfeeding, so avoid it there. The few trials that included women were short, so its effects in women are not well established.
Start slow, be smart, read the research, and consult a professional if you have any concerns. This is here to inform your choice, not make it for you.
Common Questions
Does tongkat ali actually raise testosterone?
Modestly, and only for some men. The pooled figure is an average, and some men in the trials got no measurable change. The likeliest responder started low or older; a younger man in the normal range is likeliest to feel nothing.
Should I stack tongkat ali with Fadogia agrestis?
They are packaged together for marketing reasons. Only tongkat ali has human trials behind it; Fadogia agrestis has none.
Explore Related
Other pages this one connects to, by the evidence they share, the outcomes they touch, and the ground they cover.
All 13 sources on this page independently checked and cross-referenced.
Thomas Dehli, Founder & Editor, Sacred Lotus
Sacred Lotus has published Chinese medicine reference material since 2001. Integrative pages are held to the same standard as the herb and formula library: cite the source, grade the claim at its real strength, and say where the research has not looked. This page is educational and it is not medical advice. Last reviewed and updated August 9, 2026.
Evidence strength
How confidently the research supports a claim. Strength describes the evidence, not our endorsement.