Tongkat Ali and Testosterone: Scientific Review on Benefits and Side Effects
Tongkat Ali has developed a reputation for being a powerful testosterone booster, but does it actually work?
In this article I break down everything there is to know about tongkat ali and its interaction with testosterone levels in men.
What is Tongkat Ali?
Tongkat Ali (aka Eurycoma Longifolia Jack, Malaysian Ginseng, or Longjack) is a herb native to Indonesia, Malaysia, Thailand, Vietnam, and Laos. Traditionally, it has been used all over South East Asia to treat a variety of conditions.
In Indonesia and Malaysia, the root of tongkat ali is boiled in water, and the water is consumed to help with erectile dysfunction and to provide relief from fever, intestinal worms, and jaundice (1). In Vietnam, the flower and fruits are used to treat digestive issues, and the root is used to treat malaria and fever (2).
Today, tongkat ali is readily added to supplements for its supposed testosterone boosting abilities and to improve overall sexual health, energy, and stamina.
Does Tongkat Ali Increase Testosterone Levels In Humans?
Supplement manufacturers use animal and test-tube studies to make claims that their products are "scientifically proven" to work. Technically speaking, their statements are correct. But in a lot of cases, the same effects don't go on to affect humans in the same way.
The following are 5 studies that have observed how tongkat ali supplementation affects testosterone levels in humans.
Human Trial #1
Number of Subjects
76 men suffering from late-onset hypogonadism (low testosterone) were given 200mg of tongkat ali for 1-month.
Serum testosterone levels were measured both before and after the 30-days of treatment. Subjects also completed the Aging Males' Symptoms (AMS) questionnaire.
AMS is the most commonly used scale to measure health-related quality of life and symptoms in aging males.
At the start of the experiment, 35.5% of the men had normal testosterone levels and only 10.5% of them did not show any complaint of symptoms according to the AMS scale.
After 1-month of supplementating with tongkat ali, 90.8% had testosterone levels in the normal range and 71.7% showed normal values according to the AMS scale.
Key takeaway: I was unable to get access to the full research paper. As such, the summary above is based on the abstract. So I'm not exactly sure what the researchers defined as "low testosterone" and by how much the subjects' testosterone levels increased. These are questions that can only be answered by having a look at the full research paper. That being said, a positive interaction between Tongkat Ali supplementation and testosterone levels is evident.
Human Trial #2
Number of Subjects
109 men (aged 30-55) were randomly assigned to ingest a daily dose of either 300mg of tongkat ali or placebo for 12-weeks.
The primary measures for this experiment were the Quality of Life questionnaire and physical fitness tests (flexibility, strength, endurance).
Secondary measures included the Sexual Health questionnaire, International Index of Erectile Dysfunction questionnaire, hormonal profiles (free testosterone, total testosterone, IGF-1, DHEA, SHBG), semen analysis, and body composition.
All measurements were taken once on day 0, once at the 6-week mark, and once at the 12-week mark.
In the Quality of Life questionnaire, the difference in scores between groups was not statistically significant other than in the "physical functioning" and "vitality" sections; the tongkat ali group had significantly better scores in both. As for the physical fitness tests, no major differences were noted between groups.
No significant differences were noted between groups in the Sexual Health questionnaire either, but the tongkat ali group scored significantly better in the Erectile Function (IIEF) questionnaire. Hormonal profiles and body fat were also similar between groups.
The tongkat ali group did show major improvements in seminal parameters though. An 18.2% increase in semen volume and 44.4% increase in semen motility.
Key takeaway: Tongkat ali supplementation had no significant influence on testosterone levels.
Human Trial #3
Number of Subjects
63 subjects (32 men, 32 women) were screened for moderate stress and were randomly assigned to receive a daily dose of either 200mg of tongkat ali or placebo for 4 weeks.
Mood State and Hormonal Profiles were assessed before and after the 4-weeks of supplementation.
Mood State (Vigor, Depression, Anger, Confusion, Fatigue, and Anxiety) was measured using the Profile of Mood States (POMS) survey.
Hormonal profiles (coritsol, testosterone) were measured using saliva samples.
After 4-weeks of supplementation, the tongkat ali group showed significant improvements in tension (-11%), anger (-12%), and confusion (-15%) compared to placebo.
The tongkat ali group also had significantly lower cortisol levels (-16%) and higher free testosterone levels (+37%) compared to placebo.
Key takeaway: This is a more promising study, but keep in mind that the subjects were screened for stress. A 37% increase in T in 4-weeks is pretty drastic, but it's not for sure that the same effects will carry on to affect men that are otherwise healthy and without stress.
Human Trial #4
Number of Subjects
13 men and 12 women (aged 57-72) were given 400mg of tongkat ali extract for 5 weeks.
Fasted blood samples were collected 3 times: once before supplementation, once at the 3-week mark, and finally at the 5-week mark.
Muscular strength was assessed via a handgrip dynamometer test before each blood sample.
5-weeks of supplementation allowed men to increase total testosterone levels by 15.1%, free testosterone levels by 61.1%, and grip strength by 16.6%.
Key takeaway: When testosterone is released into the blood stream, most of it (about 95%) gets bound to SHBG. Bound testosterone is unable to exert an influence on your body. Free testosterone is what provides all the benefits. The fact that tongkat ali supplementation increased free testosterone levels by 61.1% is very interesting to note.
Human Trial #5
Effects of a Proprietary Freeze-Dried Water Extract of Eurycoma longifolia (Physta) and Polygonum minus on Sexual Performance and Well-Being in Men: A Randomized, Double-Blind, Placebo-Controlled Study.
Number of Subjects
26 healthy men were randomly assigned to ingest a daily dose of either 300mg of tongkat ali or placebo for 12-weeks.
The two primary aims of this experiment were to see how tongkat ali supplementation affected sexual performance and quality of life. To assess these measures, subjects completed a series of subjective surveys.
The tertiary objective of this study was to measure the affect of tongkat ali supplementation on serum testosterone levels.
Researchers reported that the subjects receiving supplementation had significantly improved scores on subjective measures of libido and improved sexual performance compared to placebo.
In the subjects receiving tongkat ali, total testosterone levels went up 10.36% while free testosterone levels actually dropped by 18%.
Key takeaway: Although tongkat ali supplementation increased total testosterone levels by 10%, the decrease in free testosterone levels is definitely not desirable. As mentioned above, it is free testosterone that exerts its influence on your body.
The Bottom Line: Tongkat Ali Is a Potential Testosterone Booster
Out of the 6 human trials studying the effects of tongkat ali supplementation on testosterone, 3 show an increase, 1 shows no impact, while one shows an increase in total T and a decrease in free T.
More evidence than not shows tongkat ali to have a positive influence on testosterone.
But keep in mind that a lot of the studies that showed the best results had subjects who had very low testosterone levels to begin with (and therefore a very wide room for improvement), were moderately stressed, or were elderly (57+). If you don't meet these criteria, don't expect supplementation to impact your testosterone levels to the same extent.
Key takeaway: The current state of research is inconclusive, but more evidence than not shows tongkat ali supplementation to increase testosterone levels. The best results were seen in men who had very low testosterone levels to begin with, were moderately stressed, or were elderly (over 57).
Tongkat Ali for Bodybuilding
In Human Trial #4 cited above, the men supplementing with tongkat ali gained 17% more grip strength. This does not directly translate to bodybuilding benefits, but it's still interesting to note since grip strength is a solid indicator of overall body strength as well.
In another study, researchers recruited 14 healthy men and put them on an intense resistance-training program (alternate days) for 5 weeks. During this time, each participant was also randomly assigned to ingest a daily dose of either 100mg of tongkat ali or placebo. Body composition, arm circumference, and 1-rep max (exercise not mentioned), were recorded once at baseline and once at the 5-week mark (3). Men supplementing with tongkat ali gained more muscle (2.13kg), lost more body fat (-2.86%) and had bigger arms (+0.7 inches) compared to placebo.
Key takeaway: Tongkat ali supplementation seems to be effective at speeding up muscle growth and fat-loss, but more research is needed to confirm this effect.
Other Tongkat Ali Benefits
Tongkat ali is still relatively new to the west and, as such, the only human trials performed with it have looked into its impact on testosterone and exercise performance. The benefits listed below have been found in animal and test-tube studies, so its not for sure that they will carry on to affect humans the same way. Either way, here are some potential benefits of tongkat ali supplementation:
- Aphrodisiac (4)
- Anti-anxiety (5)
- Pro-erectile (6, 7)
- Improved bone mineralization (8)
- Estrogen blocker (9, 10)
Tongkat Ali Side Effects
According to WebMD, supplementing with tongkat ali is possibly safe when taken for 9 months. But some other anecdotal reports of side-effects I've seen include:
- Increased heart rate
The Down and Low on Tongkat Ali
Tongkat ali is amongst my favorite ingredients to see in test boosters because more evidence than not supports its ability to increase testosterone levels. There's a lot more evidence for it than other more popular ingredients like fenugreek or tribulus terrestris. It is still not definitively proven to have a positive impact, but if you see it on the ingredient profile, you at least know that it has a potential benefit. You can only be sure by actually using it and getting your before/after measurements.
TL;DR: Based on the current state of the research, Tongkat Ali has powerful testosterone boosting effects in men diagnosed with andropause (low T), in moderately stress men, and in the elderly. Whether the same effects carry on if you don't meet these conditions still remains to be seen.