Tongkat ali is a plant from Southeast Asia that’s traditionally used in herbal medicine. 

Recently, it’s become popular in the health and fitness space because some people believe it also boosts testosterone, libido, and athletic performance.

Is this true, or are supplement sellers guilty of overhyping its benefits?

Here’s what science says.


What Is Tongkat Ali?

Tongkat ali, also referred to as longjack, Malaysian Ginseng, and Eurycoma longifolia Jack, is a herbal folk medicine native to Southeast Asia.

Over the centuries, people have used tongkat ali to treat a range of maladies, including low-back pain, indigestion, fever, jaundice, malaria, dysentery, and high blood pressure, but its most common use is as an aphrodisiac.

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What are Tongkat Ali Supplements?

Tongkat ali supplements are pills containing tongkat ali powder that people take as dietary supplements.

Typically, men take tongkat ali supplements to treat conditions that affect their sexual health, such as erectile dysfunction, low sex drive, and male infertility.

Recently, tongkat ali supplements have become increasingly popular among weightlifters because many believe they boost testosterone and athletic performance.

Tongkat Ali: Benefits

Here are the most commonly claimed benefits of tongkat ali and what science says about each.

Tongkat ali and Testosterone

Studies on rodent cells and “sexually sluggishrats (rats with little interest in sex) show that tongkat ali may increase testosterone, though research on castrated rats failed to replicate these findings. 

One study showed that healthy rats given tongkat ali for 12 weeks gained more muscle than rats that didn’t receive a supplement over the same period, hinting that tongkat ali may crank up testosterone production. Unfortunately, the researchers didn’t measure testosterone levels in this study.

Human studies show that supplementing with tongkat ali may boost testosterone production in men with low testosterone.

For example, in one study conducted by scientists at the University of Santa Catarina State, men with low testosterone who supplemented with tongkat ali for 6 months increased their testosterone levels by 43%. In the same study, men who only lifted weights 3 days per week increased their testosterone by ~30%, and those who lifted weights and took tongkat ali saw an almost 50% rise in “T.”

While these increases seem large, these men started with low testosterone. Thus, even though the gains were significant, they were just enough to take the men out of the “low” range and into the “natural” range. If you already have healthy levels of testosterone, it’s unlikely that you’d experience similar increases from tongkat ali supplements.

For instance, the only study to show that tongkat ali boosts testosterone in young, healthy men showed that taking 600 mg per day (a large dose) increased testosterone by 15% after 2 weeks. 

Although this result is promising, the increase is likely too small to significantly affect body composition. What’s more, the researchers didn’t follow up with the participants, so we don’t know how short-lived these increases were.

Several studies also cite research conducted by MI Tambi to bolster their argument that tongkat ali increases testosterone. Tambi’s studies showing the positive effect of tongkat ali on testosterone aren’t available online, though, making it impossible to assess their credibility. 

The only other evidence that tongkat ali affects testosterone levels comes from studies funded by supplement companies that make a tongkat ali supplement. Some of these studies suggest that tongkat ali increases testosterone, and others don’t, making it difficult to draw a conclusion either way.

At bottom, the research on tongkat ali’s effect on testosterone is hit or miss. Most research suggests that men (and animals) with low testosterone may benefit from taking tongkat ali. For everyone else, there’s little evidence that it’s effective. 

Tongkat ali and Male Sexual Health

Multiple studies show that tongkat ali has aphrodisiac effects in rats that are sexually sluggish, naive, and experienced; asexual; or otherwise healthy.

Research in humans is promising, too. In one study conducted by scientists at Universiti Sains Malaysia, men who supplemented with 300 mg of tongkat ali extract daily for 6-to-12 weeks increased subjective measures of libido by -8-to-11%.

Animal and human studies also show that tongkat ali positively affects erectile dysfunction and increases fertility by improving sperm motility and concentration.

Thus, there’s reasonable evidence that tongkat ali improves male sexual health, especially for those suffering from low libido, erectile dysfunction, and poor fertility.

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Tongkat ali and Athletic Performance

There’s no evidence that tongkat ali enhances endurance performance, though some small-scale studies and published abstracts show it has a positive effect on strength.

For example, in one study published in the International Journal of Engineering Research and Sports Science, men who took 100 mg of tongkat ali daily and performed circuit training 3 times weekly for 8 weeks increased their strength significantly more than those who took a placebo and followed the same training program.

The group taking tongkat ali also increased their overall muscle mass by 4%, while the placebo group gained no muscle.

Other studies that show dramatic improvements in strength after taking tongkat ali are funded by supplement companies whose primary product is a tongkat ali supplement. Interestingly, these studies also show that tongkat ali doesn’t change your body’s ratio of testosterone to epitestosterone.

This is significant because supplements (*cough* steroids *cough*) that significantly boost strength  ordinarily alter this ratio, making them easily detectable by drug tests. 

This prevents athletes who compete in drug-tested competitions from taking these supplements—if they did, they’d be “popped” for doping.

In other words, the authors of these papers claim that tongkat ali greatly boosts strength in a way that makes it undetectable to the drug tests used by organizations such as the World Anti-Doping Agency (WADA)—which is convenient. 

While we can’t say for certain that these results are colored by financial interest or the result of scientific malpractice, it’s sensible to wait until a disinterested third party replicates them before taking them as read (which hasn’t happened yet).

Tongkat ali and Stress

Some people believe supplementing with tongkat ali reduces stress hormone levels and improves mood. However, there’s little strong evidence this is true.

One study published in the Japanese Journal of Pharmacology found that tongkat ali treated symptoms of anxiety as well as anti-anxiety medication in mice. 

In another study funded by a tongkat ali supplement manufacturer, 63 adults suffering from stress reduced cortisol levels by 16% after taking 200 mg of tongkat ali daily for a month.

Furthermore, an observational study published in the journal Clinical Interventions in Aging found no difference in depressive symptoms between people who took tongkat ali as part of their supplement regimen and those who didn’t.

Given the lack of good research on the effect of taking tongkat ali on stress, it’s impossible to say whether tongkat ali can help treat stress.

Tongkat Ali: Side Effects

Despite its long-term use in Southeast Asia, we know little about tongkat ali’s safety profile.

That said, most studies report few side effects.

As with most herbal supplements, tongkat ali supplements may contain natural toxins or microbial contaminants or be contaminated with toxins and heavy metals. 

For example, in two studies conducted by scientists at University Science Malaysia, researchers found that out of 100 tongkat ali products, 17% contained dangerously high levels of lead, and 26% contained dangerously high levels of mercury.

Taking products that contain high levels of heavy metals can cause side effects such as loss of appetite, headaches, hypertension, abdominal pain, kidney dysfunction, fatigue, sleeplessness, arthritis, hallucinations, and vertigo.

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Tongkat Ali: Dosage

Most studies use doses of 200-to-400 mg per day.

Some short-term research suggests taking up to 1.2 grams per day is safe, though we don’t know if it confers any benefit or if it’s safe to take this amount over a longer period.

Research suggests that it’s only safe to take tongkat ali orally, as any other means could enhance toxicity by ~100-fold. In the same writeup, the researchers suggest doses of 195 mg per pound of body weight per day and over are toxic and may increase the weight of your liver, kidneys, spleen, and testes. 

FAQ #1: What’s the best tongkat ali supplement?

There’s little scientific evidence that tongkat ali boosts testosterone in healthy men, improves athletic performance, or reduces stress. As such, I can’t recommend any tongkat ali supplements, let alone say which is best.

If you want science-backed supplements that have similar effects to tongkat ali, here’s what I recommend:

  • Nigella sativa, coenzyme Q10 (CoQ10), and ashwagandha root extract: Together, nigella sativa, CoQ10, and ashwagandha root extract can increase testosterone levels, protect sperm structure and function, and help restore lost fertility in men. If you want a multivitamin that contains clinically effective doses of all three, and 28 other ingredients designed to enhance your health and mood and reduce stress, fatigue, and anxiety, try Triumph.
  • Creatine: This will boost muscle and strength gain, improve anaerobic endurance, and reduce muscle damage and soreness from your workouts. If you want a 100% natural source of creatine that also includes two other ingredients that boost muscle growth and improve recovery, try Recharge.
  • Rhodiola rosea and bilberry extract: Studies show that rhodiola rosea improves mood and reduces symptoms of stress and depression, and bilberry extract enhances mental well-being. If you want a supplement that contains clinically effective doses of both, and two other ingredients that balance hormone and energy levels and reduce stress and fatigue, try Vitality.

(Or if you aren’t sure if these supplements are right for your budget, circumstances, and goals, take the Legion Supplement Finder Quiz! In less than a minute, it’ll tell you exactly what supplements are right for you. Click here to check it out.)

FAQ #2: Are the “tongkat ali before and after pictures” you find online real?

Because many supplement sellers claim tongkat ali boosts testosterone, they often market their products with “tongkat ali before and after pictures“ showing men who have gained muscle and lost weight.

You probably shouldn’t believe these pictures, though.

Supplement companies produce these images to sell their products, which means there’s a good chance they’ve been doctored to appear more impressive than they are.

Or, they simply show men who improved their body composition with other proven methods like high-protein dieting and strength training and are attributing the benefits to tongkat ali.

If you’d like to follow an exercise and diet program that will help you gain muscle and lose fat like clockwork, check out my fitness books for men and women, Bigger Leaner Stronger and Thinner Leaner Stronger.

(Or if you aren’t sure if Bigger Leaner Stronger or Thinner Leaner Stronger is right for you or if another strength training program might be a better fit for your circumstances and goals, take Legion Strength Training Quiz, and in less than a minute, you’ll know the perfect strength training program for you. Click here to check it out.)

FAQ #3: Should I believe online tongkat ali reviews?

Probably not.

There’s little evidence that tongkat ali supplements boost testosterone and athletic performance or lower stress. Anyone who writes a review stating otherwise is probably experiencing the placebo effect or has been paid by a supplement company to promote their product.

+ Scientific References