Testosterone (T) supplement ads scour the internet, claiming to increase testosterone, libido, and general "manliness." However, most "T booster" supplements do not have ingredients to support their claims. Americans spend billions of dollars on dietary supplements, even though most products show little if any, evidence of benefits.
On average, T boosters contain eight different ingredients, but some options have more than 50 – most are plant and herbal extracts, vitamins, minerals, and other micronutrients. In addition, testosterone boosters usually include ingredients from traditional remedies, such as fenugreek, zinc, maca, and ashwagandha.
Testosterone replacement therapy (TRT)
As men age, there is a progressive decline in T of about 0.4 to 2.0% per year after age 30. Men in their 70s have average T levels about 35% lower than younger men. Reasons for this T decline include:
- Failure of the testes to produce T.
- Impaired function of the hypothalamic-pituitary-gonadal (HPG) axis.
- Comorbid medical issues.
- Exogenous medications.
Hypogonadism (testosterone deficiency) is diagnosed when total serum T levels are below 300 ng/dL combined with symptoms that include decreased libido and bone density, erectile dysfunction, fatigue, weakness, and increased body fat and sweating.
Despite TRT's well-documented beneficial effects on erectile function, bone marrow, muscle mass, strength, fatty tissue, and metabolism, only about 5% of hypogonadal men receive T treatment. The cost and lack of insurance coverage for T treatment may be a primary reason. In addition, patients may hesitate to try TRT because they conflate TRT with anabolic steroids. Other patients may worry about TRT's side effects, health risks, and embarrassment in presenting their symptoms of low T to their healthcare provider. Hence, instead of TRT, 50% of American adults consume dietary supplements, including "T boosters," hoping to increase T.
The American Association of Clinical Endocrinologists and the American Urological Association do not recommend testosterone supplements; however, they recommend TRT in patients with clear signs and symptoms of hypogonadism.
Testosterone supplement companies comparable to the wild west
The supplement industry is notoriously suspect and is the economic wild-west. The industry is largely unregulated and has a track record of getting away with selling useless and sometimes dangerous products.
The FDA oversees both supplements and medicines, but the regulations for dietary supplements differ from prescription or over-the-counter medication. According to the FDA, nutritional supplements "are not intended to treat, diagnose, prevent, or cure diseases," and "claims like these can only legitimately be made for drugs, not dietary supplements." Despite the FDA's position, nutritional supplements continue to claim or imply that they affect medical conditions.
In addition, supplement companies are responsible for evidence that their products are safe and that their labels are truthful. However, they do not have to provide safety evidence to the FDA before marketing their product if it does not contain a new dietary ingredient.
Dietary supplements can make unsubstantiated medical claims if the claim is followed by, "The FDA has not evaluated this statement. This product is not intended to diagnose, treat, cure, or prevent any disease."
Still, the FDA monitors the marketplace for potential illegal products that are misleading or may be unsafe. In addition, the FDA can take legal action against companies and websites that sell dietary supplements when the companies make false claims about their products.
Studies do not support testosterone-boosting and composition claims
A 2020 study evaluated 50 "T booster" supplements for active ingredients and product claims. Researchers evaluated each supplement for literature that supported the claim, as well as Recommended Daily Allowance (RDA) and upper tolerable intake level (UL). Results showed 90% percent of the supplements claimed to "boost T," although only 25% had data to support these claims. Moreover, data showed 10% decreased testosterone, while 18% showed no change in T.
There was no data on the effect of T for 62% of the supplements– a 2018 study showed minimal human studies on T boosters, resulting in no definitive efficacy findings.
Many supplements had therapeutic doses of vitamins and minerals that exceeded recommended levels and were occasionally over the UL. On average, the supplements contained 1,291% of the RDA for vitamin B12, 808% for vitamin B6, 272% for zinc, 200% for vitamin B5, and 188% for vitamin B3. Thirteen of the products exceeded US Food and Drug Administration for the UL of ingredients (Zinc, vitamin B3, and magnesium).
Testosterone booster advertising not based on science
Science-Based Medicine (SBM) is a non-profit organization with no corporate or government sponsorship dedicated to the non-biased evaluation of medical treatments and products in a scientific light. According to SBM, testosterone-booster claims consist of suggestions and innuendo with no testable science. For example, in a review of Nugenix Total T, one of many newer T boosters, a commercial shows men on a golf course saying their sexual performance had gone downhill and some men stating that Nugenix Total T had restored their performance.
In the ads for T boosters, extensive and vague symptom lists virtually guarantee that any middle-aged man will self-diagnose low T. Also, free samples are usually offered, with a catch: there are only enough for two weeks, while they say results may take 30 days. Finally, you are automatically signed up for regular shipments upon accepting the free samples.
Testosterone boosters in athletics
Some testosterone supplements claim to be "all-natural," and their product labels list only permitted substances, which makes the product seem safe. In addition, the product advertising insinuates they are natural, legal, and effective ways to boost testosterone to gain a competitive edge and won't cause an anti-doping violation.
However, prohibited lists include "other substances with similar chemical structure or similar biological effects." This wording allows for the possibility that the product could contain a banned substance. In addition, although a supplement does not have a prohibited ingredient, there could still be contamination issues with the product that could generate a positive test for banned substances.
The U.S. Anti-Doping Agency bans substances that enhance physical performance, are a health risk, or otherwise violate the spirit of the sport. In fact, according to a 2018 report by the World Anti-Doping Agency, 1,640 sports supplements contain banned substances. In addition, illegal steroids sometimes contaminate common supplements.
Effective nutritional supplements
Tongkat ali (TA) and fadogia agrestis are two supplement ingredients that may be exceptions to the rule, providing a slight boost in testosterone. TA roots are a traditional "anti-aging" remedy to improve libido, energy, sports performance, and weight loss. Results of one study indicate that daily tongkat ali root extract improves stress hormone profile and specific mood state parameters and may be an effective shield from the detrimental effects of stress. In addition, TA may reduce sex-hormone-binding globulin (SHBG), which may enhance free testosterone availability, which has positive implications for libido, muscle growth, and overall well-being.
Fadogia agrestis, known for its aphrodisiac effects, may increase libido, and testosterone, which can contribute to increased muscle mass, strength, and overall physical performance. Most studies have been conducted on animals, and human studies are needed.
Tonghat ali and fadogia agrestis will not significantly boost testosterone levels but may mildly increase some testosterone parameters. Patients taking these supplements should have regular bloodwork and be followed by a medical provider.
Studies that review the effects of T boosters are sparse. In addition, T supplements are not regulated as stringently by the FDA in the same way as medications. With fitness and weight control emerging as popular health goals, the pursuit of supplements claiming to increase endogenous T naturally has increased. However, there is little evidence supporting their use. If you need T, consider TRT, not products falsely claiming to boost T.