Take-home points
- Most active ingredients in ‘testosterone booster’ supplements have not demonstrated to increase testosterone.
- The safety of ‘testosterone booster’ supplements is questionable - the lack of safety regulations in the supplement industry is concerning.
- Testosterone replacement therapy is the most effective and clinically supported treatment to increase testosterone levels.
What is testosterone?
Testosterone is one of many androgen hormones which affect the brain, body, and behaviour. It links to many areas of health but most often with energy levels, sexual function, and muscle and bone development. In men, the testicles produce most testosterone. In women, albeit in much smaller amounts, the ovaries produce testosterone.
Learn more about the role of testosterone in the body
Why do people want to boost testosterone?
There are a couple of main reasons why people, men in particular, wish to boost their testosterone levels. We often hear or read about these in magazines, on product labels, or from the gym enthusiast with all the tips and tricks to ‘hack your health.’
The first reason is to reap the illustrious benefits of high (above average) testosterone levels. High testosterone levels as a defining masculine trait is a narrative that has survived centuries, with traditional stereotypical masculinity characterised by traits such as toughness, emotional control, physical strength, competitiveness and sexual competency. Even among men today, those with the most testosterone are often viewed as the most genetically gifted, or the ‘most manly’.
The second reason - and one that we would argue is more scientifically sound - is to avoid or reverse the detriments of low testosterone. In contrast to the supposed benefits of high testosterone levels, people with low testosterone commonly report fragility, fatigue, and sexual health concerns. Indeed, a wide range of studies now support the notion that low testosterone is a cause of symptoms such as:
- Decreased sex drive (low libido).
- Erectile dysfunction.
- Depressed moods.
- Irritability.
- Anaemia.
- Weakness.
- Reduced muscle mass and bone densit.
- An increased risk of falls and fractures.
People with an interest in long-term health may also be aware that low testosterone links with conditions such as type 2 diabetes, cardiovascular disease, and obesity, although whether testosterone is a cause or product of these conditions is still debated.
What are the testosterone boosting supplements (testosterone boosters)?
Some supplements to boost testosterone focus on just one active ingredient, while others contain a mixture of active ingredients. Reputable supplement companies typically state the dose of each ingredient, so you know what you are getting, but a ‘proprietary blend’ of ingredients with no dosing information is often used to bypass supplement regulations.
The 10 most common ingredients in testosterone-boosting supplements are:
- Tribulus Terrestris
- Ashwagandha
- DHEA (Dehydroepiandrosterone)
- D-Aspartic acid
- Fenugreek
- Zinc
- Magnesium
- Vitamin D3
- Horny Goat Weed
- Yohimbine
Do testosterone boosters work?
When considering which testosterone booster is best, unfortunately, they are largely ineffective. Chase Clemesha and his research team evaluated 50 “Testosterone booster” supplements and found that only 24.8% contained ingredients that demonstrably increase testosterone; strikingly, 61.5% of the testosterone supplements used ingredients that had not been studied for testosterone, 18.3% used ingredients which did not change testosterone levels, and 10.1% had data showing a decrease in testosterone.1
A major concern is that from 191 studies of the active ingredients in the top 5 ‘Testosterone Booster’ Amazon supplements, only 19% were human studies. And only 30% of these human studies reported a testosterone increase.2 A recent scientific review of active ingredients in testosterone supplements said that “19% of ingredients received an A grade for strong positive evidence with net positive evidence in two or more randomized controlled trials… 68% received C or D grades for contradicting, negative, or lacking evidence.”3 The sad reality is that most studies on testosterone-boosting ingredients are conducted on animals or in petri dishes.
Do not be fooled by favourable Amazon supplement reviews either. Although the top 5 Testosterone Boosters on Amazon have an average review score of 4.56 out of 5, it is no secret that online reviews are subject to predatory habits by vendors, fake ‘computer bot’ and paid consumer reviews.2 In fact, out of the 13,806 reviews (in 2019) for the 5 Amazon ‘Testosterone Booster products’, a popular metrics tool for evaluating Amazon reviews (ReviewMeta, which identifies unverified purchases, incentivized reviews, and phrase repetitions) considered 66.6% of them untrustworthy.
Here are TRTed, we do not consider all testosterone supplements useless - some may provide a modest testosterone ‘boost’ - but the persistent issue is not knowing which active ingredients are effective and in what situation. To all the common ingredients we have encountered in testosterone booster supplements, evidence is consistently scarce, mixed, and requires more vigorous investigation. We await a scientific review from experts that promotes the efficacy and safety of a particular over-the-counter ingredient or product.
Are testosterone boosters safe?
There are two main concerns about the safety of testosterone-boosting supplements: contamination of non-listed ingredients, and unwanted side effects of high doses.
The first issue regarding the contamination of non-listed ingredients is often overlooked, and applies to the supplement industry generally. Specifically of note, while the safety, purity, and efficacy of pharmaceutical products is thoroughly and continuously controlled, there are no premarket safety requirements for supplement manufacturers in Europe and the United States.4 There are also no obligatory tests about the quality and quantity of the active ingredients, i.e. checking the ingredients and doses on the label align with those in the product. Studies have found that many supplements contain substances like prohormones or anabolic androgenic steroids, that may boost testosterone, but not in the way you intend.5 In one analysis of 3132 dietary supplements, researchers found that “more than 28% of the analyzed dietary supplements pose a potential risk of unintentional doping.”6
The second potential issue is that some active ingredients in testosterone boosting supplements have been linked with adverse effects, at least in high doses. The evidence is fairly weak, to be clear, but there are reports of tribulus contributing to gynocomastia (the development of breast tissue), ashwaganda inducing liver injury,7 and magnesium triggering diarrhea.8 These are by no means ‘facts’ but the lack of evidence that testosterone-boosting supplements are safe is concerning, particularly when supplements are not well regulated, sometimes contaminated, and commonly hide dosing information behind ‘proprietary blends’. That said, some active ingredients in testosterone-boosting ingredients have stronger evidence of safety in certain dose ranges: DHEA,9 yohimbine,10 and vitamin D3.11 Therefore, if you can access such ingredients from well-respected supplement companies and consume the tolerable doses suggested, such active ingredients may be consumed safely.
Testosterone replacement therapy vs. testosterone boosters
Testosterone-boosting supplements and testosterone replacement therapy (TRT) share the same goal but are not comparable treatments. Only TRT contains testosterone; testosterone boosters, on the other hand, intend to indirectly boost testosterone production. Typically, health professionals will only use TRT to treat low testosterone, as there is an abundance of evidence supporting their efficacy in men with low testosterone. Unlike supplements, TRT cannot be purchased over-the-counter.
The US Food and Drug Administration (FDA) clearly states that, “Unlike drugs, supplements are not intended to treat, diagnose, prevent, or cure diseases. That means supplements should not make claims, such as “reduces pain” or “treats heart disease”.12 Claims like these can only legitimately be made for drugs, not dietary supplements.”
Read more about the benefits of testosterone replacement therapy in patients with hypogonadism
Join the conversation on the TRTed Community!
References:
- Glemesha CG et al. World J Mens Health 2020;38(1):115-122.
- Balasubramanian A et al. J Sex Med 2019;16(2):203-212.
- Kuchakulla M et al. Int J Impot Res 2021;33(3):311-317.
- Wierzejska RE. Int J Environ Res Public Health 2021;18(17):8897.
- De Cock KJ et al. J Pharm Biomed Anal 2001;25(5-6):843-52.
- Kozhuharov VR et al. Biomed Res Int 2022;2022:8387271.
- Lubarska M et al. Int J Environ Res Public Health 2023;20(5):3921.
- Fine KD et al. N Engl J Med 1991;324(15):1012-7.
- Panjari M et al. Maturitas 2009;63(3):240-5.
- Vogt HJ et al. Int J Impot Res 1997;9(3):155-61.
- Johnson KC et al. Eur J Clin Nutr 2022;76(8):1117-1124.
- Available at (Accessed on 14/08/2023): https://www.fda.gov/food/dietary-supplements/dietary-supplement-ingredient-directory.