High testosterone levels improve just about every aspect of your health, fitness, and well-being.
They give you energy, enhance muscle growth, fat loss, and recovery, help you sleep, improve your mood, boost your sex drive, and more.
It’s no wonder, then, why so many people—particularly men—seek supplements that rev up their natural testosterone production.
How effective are so-called “testosterone boosters,” though?
Are testosterone boosters safe?
And what’s the best testosterone booster on the market?
Get evidence-based answers to these questions and more in this article.
Table of Contents
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What Is a Testosterone Booster?
A testosterone booster is a dietary supplement typically containing vitamins, minerals, nutrients, and herbs that purportedly increase your testosterone levels.
They differ from testosterone replacement therapy (TRT) because they don’t contain actual testosterone, only ingredients your body may use to increase its natural testosterone production. Doctors also have to prescribe TRT, whereas you can buy testosterone boosters over the counter.
Likewise, they’re different from anabolic steroids because, unlike steroids, testosterone boosters won’t raise testosterone levels to supraphysiological (beyond what’s possible naturally) levels. Moreover, testosterone booster supplements only contain legal substances, whereas steroids are illegal.
What Do Testosterone Boosters Do?
The most commonly touted testosterone booster benefits include increased energy levels, improved libido and sexual function, faster muscle growth, strength gain, and recovery, reduced body fat, and enhanced sleep and mood.
Supplement sellers claim that testosterone boosters achieve these benefits by boosting your body’s natural testosterone production.
Do Testosterone Boosters Work?
Testosterone booster ingredients vary from product to product. Let’s look at the most common ingredients found in testosterone booster pills and powders to see which, if any, do what they claim.
Creatine
Creatine is a natural compound composed of the amino acids L-arginine, glycine, and methionine. It’s the most researched sports supplement on the market and widely taken for its performance- and recovery-boosting effects.
Many people also believe that creatine increases testosterone.
This is based mainly on the results of three studies: two that found that people who supplemented with creatine significantly increased their testosterone, and one that found rugby players who took creatine saw an increase in dihydrotestosterone, a hormone converted from testosterone.
While these results seem promising, they’re the exception rather than the rule. All other research shows that creatine has no effect on testosterone.
Overall, it’s safe to say that creatine isn’t the “T” booster that many claim. That said, creatine enables you to train harder. And since intense exercise raises testosterone levels, creatine may indirectly cause your T levels to trend in the right direction.
D-Aspartic Acid
D-Aspartic Acid (DAA) is an amino acid that interacts with the brain’s N-methyl-D-aspartate (NMDA) receptors.
According to the results of animal and human cell studies, this interaction should trigger a train of events that spurs the testes to produce more testosterone.
That’s the theory, at least. However, in studies on living humans, the effect is unpredictable.
In one study published in the journal Reproductive Biology and Endocrinology, healthy men who took DAA daily for 12 days increased their testosterone by 42%. Three days after they stopped taking the supplement, their T levels were still 22% higher than they had been at the beginning of the experiment.
A similar study that used the same DAA supplement (brand name DADAVIT) reported that infertile men who took DAA daily for 90 days increased testosterone levels by 30-to-60%.
In contrast, studies on weightlifters show that taking DAA has either no impact on testosterone levels or that it causes T to decline.
For example, in one study conducted by scientists at the University of Western Sydney, researchers found that weightlifters who took 3 grams of DAA daily for 2 weeks saw no change in their testosterone levels. Interestingly, those who took 6 grams of DAA daily for the same period experienced a decrease in testosterone.
These haphazard results make it difficult to know how DAA affects testosterone. Until more high-quality studies show that DAA boosts T, it’s probably sensible to give it a wide berth.
Ashwagandha
Ashwagandha is a plant root commonly used in Ayurvedic (traditional Indian) medicine. It’s known as an adaptogen, which is a compound that causes an imperceivable level of stress in the body that trains it to better handle future stresses.
There’s evidence that ashwagandha increases testosterone, though this effect is conditional.
For example, ashwagandha boosts testosterone in men who have low testosterone caused by fertility issues related to stress or poor semen quality.
The only study showing ashwagandha has a positive effect on T levels not related to infertility was published in the Journal of the International Society of Sports Nutrition.
It found that men who took ashwagandha and lifted weights for 8 weeks gained almost twice as much muscle and strength, lost more than twice as much body fat, and experienced a five-fold greater increase in testosterone than those who trained and took a placebo.
While it’s tempting to get giddy over impressive figures like these, it’s prudent to remember that they’re only one trial’s results. Until scientists replicate the findings, it’s wise to remain skeptical.
At bottom, there’s good evidence that ashwagandha can restore testosterone levels in men with suppressed testosterone because of fertility issues. However, we need more evidence before we can confidently say whether it increases testosterone in healthy men.
Fenugreek Extract
Fenugreek is a herb used in Ayurveda medicine to improve general health, stimulate appetite, and boost virility.
People believe fenugreek boosts testosterone because it prevents the enzyme alpha-5-reductase from converting testosterone into estrogen, and thus simultaneously increases testosterone and decreases estrogen.
There’s some truth to this, though context is key.
Studies tend to show that fenugreek increases testosterone in older testosterone-deficient men. That said, some of these studies are funded and conducted by supplement companies that manufacture and sell testosterone booster supplements containing fenugreek. As such, it’s difficult to know how much financial interest colored the results.
In another study conducted by scientists at the University of Mary Hardin-Baylor, researchers had men with no testosterone abnormalities exercise and take 500 mg of fenugreek or a placebo daily for 12 weeks.
The results showed that exercising increased all the men’s T levels but that taking fenugreek provided no additional benefit. Fenugreek did seem to curb the increase in estrogen caused by exercise, though.
Thus, fenugreek may increase testosterone in men who have low testosterone, but it’s ineffective in otherwise healthy men.
Tribulus Terrestris
Tribulus terrestris is a herb used in Ayurveda medicine to promote male sexual wellness.
The idea that tribulus boosts testosterone stems from animal research showing that its main active compound, protodioscin, increases luteinizing hormone, which prompts the testes to crank up testosterone production.
However, several subsequent human studies have failed to replicate this finding, which is why a systematic review published in the Journal of Dietary Supplements concluded that tribulus is ineffective at increasing testosterone.
Eurycoma Longifolia (Tongkat Ali)
Eurycoma longifolia, also referred to as tongkat ali, longjack, and Malaysian Ginseng, is a herbal medicine native to Southeast Asia.
People commonly use eurycoma longifolia as an aphrodisiac, with many believing that it improves libido because it boosts testosterone.
Research only partially supports this theory.
Studies on rodent cells, “sexually sluggish” rats (rats with little interest in sex), and men with low testosterone show that eurycoma longifolia may increase testosterone.
Only one study has investigated how eurycoma longifolia affects testosterone levels in healthy men. It found that eurycoma longifolia may marginally increase testosterone but not enough to meaningfully improve body composition, energy levels, or sexual function.
All other available evidence that eurycoma longifolia increases T comes from studies funded by supplement companies that make a eurycoma longifolia supplement. Some of these studies suggest that eurycoma longifolia increases testosterone, and others don’t, making it difficult to conclude either way.
At bottom, the research on eurycoma longifolia’s effect on testosterone is hit or miss. Most research suggests that men (and animals) with low testosterone may benefit, but it’s probably a dud for everyone else.
Zinc
Zinc is a “trace mineral” (a mineral we need in small amounts) found primarily in meat, fish, seafood, and cereals.
Eating too little zinc is associated with suppressed testosterone production, which is why many believe supplementing with zinc boosts T.
While studies on zinc-deficient men and men with low testosterone often show that taking zinc improves T levels, studies on healthy men are less promising. For example, most research investigating how ZMA (a supplement containing zinc, magnesium, and vitamin B6) affects healthy men shows that zinc has no effect on testosterone.
In other words, zinc probably isn’t the T booster many claim, though it may help increase testosterone to healthy levels if you have low T, especially if zinc deficiency is the underlying cause.
Another potential upside of supplementing with zinc is that it may prevent testosterone levels from slumping after exhausting exercise (an effect commonly seen among athletes).
For instance, in studies where athletes and unfit men follow intense exercise programs, results show that those who take zinc maintain healthy testosterone levels, while those who take a placebo experience a significant drop in T.
Boron
Boron is a trace element primarily found in fruit, tubers, legumes, and alcoholic drinks, such as wine, cider, and beer.
There’s little research investigating the effects of boron on testosterone and the evidence we have is inconsistent.
For example, in one small study conducted by scientists at Tehran University of Medical Sciences, researchers gave 8 healthy men 10 mg of boron daily for a week. Blood test results taken 6 hours after the first dose showed that the men’s testosterone levels were trending upward, and after 7 days, their testosterone levels were significantly higher (~28%) than they had been at the beginning of the trial.
A previous study by the same lead researcher showed that taking boron daily for 4 weeks increased testosterone by only a small, insignificant amount (~11%).
In another study published in the International Journal of Sport Nutrition, scientists gave bodybuilders 2.5 mg of boron or a placebo daily for 7 weeks. The results showed that both groups increased their testosterone levels but that taking boron was no more effective than placebo.
Given these conflicting results, it’s too early to say how boron affects testosterone. As such, it’s probably not worth supplementing with boron until we have more evidence that it’s effective.
Testosterone Booster Side Effects
Testosterone boosters are poorly regulated and typically contain unique combinations of minimally studied compounds.
This is likely why case reports (studies of individual patients) detailing adverse testosterone booster side effects, such as abdominal pain, blood clots, and liver conditions, are not uncommon.
What’s more, research published in the World Journal of Men’s Health shows that ingredients in commercially available testosterone boosters regularly exceed recommended daily allowance (RDA) guidelines, which can have negative health consequences, and sometimes exceed the “upper tolerable intake level” (above which, adverse side effects become significantly more likely).
Ironically, data from the same paper suggests that another potential side effect of taking testosterone boosters is decreased testosterone. This is because T boosters often contain ingredients that have little scientific support.
For instance, some T boosters include ingredients such as apigenin, astragalus, and vitamin B6, all of which have been shown to lower T.
Should You Take Testosterone Booster Supplements?
If you have low testosterone, a supplement containing a clinically effective dose of ashwagandha, fenugreek, or zinc may increase your T to healthy levels.
However, if you have healthy testosterone levels, taking a testosterone booster supplement probably won’t increase your T further and most certainly won’t have effects akin to anabolic steroids.
For most people, the best way to ensure your testosterone levels are healthy is to stay lean, lift weights, manage stress, eat a healthy diet (and take a multivitamin), and maintain good sleep hygiene.
And if you want an exercise and diet program that’ll take care of most of these points, check out my fitness books for men and women, Bigger Leaner Stronger and Thinner Leaner Stronger.
(If you aren’t sure if Bigger Leaner Stronger or Thinner Leaner Stronger is right for you or if another strength training and diet program might be a better fit for your circumstances and goals, take Legion Strength Training Quiz and the Legion Diet Quiz, and in just a couple of minutes, you’ll know the perfect strength training and diet plan for you.)
FAQ #1: What is the best testosterone booster for men?
Here are the best ways for most men to boost testosterone:
- Lift weights: People who exercise regularly have higher testosterone levels. This is even true in elderly and obese people.
- Eat a healthy diet: Eat a high-carb diet with plenty of healthy fats. (And if you’d like specific advice about what diet to follow to reach your fitness goals, take the Legion Diet Quiz.)
- Minimize stress: Increased cortisol leads to reduced testosterone.
- Take a multivitamin supplement: Vitamin and nutrient deficiencies can negatively affect testosterone levels. If you want a multivitamin that contains clinically effective doses of 31 ingredients (including ashwagandha and zinc) designed to enhance your health and mood and reduce stress, fatigue, and anxiety, try Triumph. (And if you’d like more specific advice about what supplements to take to reach your fitness goals, take the Legion Supplement Finder Quiz.)
- Take a DHEA supplement: Studies show that DHEA increases testosterone production in older men and estrogen production in older women. If you want a wellness supplement that contains a clinically effective dose of DHEA as well as three other ingredients designed to make you feel fitter, livelier, and calmer, try Vitality.
- Get plenty of sleep: Sleep deficiency correlates with low testosterone.
FAQ #2: Should I trust testosterone booster reviews?
Maybe.
If someone positively reviews a testosterone booster because it helped them increase their previously low T levels, you may be able to trust the review. Just don’t forget that no one is fully immune from the placebo effect, and this likely influenced their results.
If they say taking a testosterone booster increased their T similarly to steroids, it’s probably unreliable.
FAQ #3: Can women take testosterone boosters?
Women can take testosterone boosters but need to be aware that some only work because they affect the testes. Without testes, these supplements won’t work the same in women as in men.
Testosterone boosters that work by acting on enzymes throughout the body, like fenugreek, are more viable options for women.
FAQ #4: Are testosterone boosters steroids?
No.
Supplements sold as testosterone boosters differ from anabolic steroids because they don’t raise T to unnaturally high levels and aren’t illegal.
FAQ #5: Are testosterone boosters safe?
It’s impossible to comment on the safety of testosterone boosters as a whole since every product contains different ingredients at varying doses.
That said, the most common ingredients included in testosterone boosters are generally safe and well-tolerated.
We know less about the safety profile of the more obscure ingredients often found in T boosters. Furthermore, many manufacturers include excessively high doses of some ingredients, which may cause unwanted side effects.
FAQ #6: Do testosterone boosters work for muscle gain?
If you have low testosterone and use a testosterone booster to increase your T to a healthy level, yes.
If you already have healthy testosterone levels, taking a testosterone booster is unlikely to make a noticeable difference to your body composition.
FAQ #7: What’s the best natural testosterone booster?
The best way to naturally boost your testosterone is to stay lean, lift weights, manage stress, eat a healthy diet (and take a multivitamin), and maintain good sleep hygiene.
If you do all of this and still have low testosterone, taking ashwagandha, fenugreek, or zinc may help.
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