Testosterone Supplement Claims Not Always Backed by Medical Research
“Testosterone boosting” (sometimes called “T boosting”) supplements may claim to improve a man’s testosterone levels along with his libido, muscle mass, and energy. But there is little scientific research available to substantiate such claims, according to a recent study in the World Journal of Men’s Health.
Men’s testosterone levels gradually decline as they get older. For some men, this drop leads to fatigue, moodiness, less interest in sex, and reduced muscle mass. Testosterone replacement therapy (TRT) is sometimes prescribed to alleviate these symptoms.
However, some men decide to try dietary supplements instead, feeling that it is a more “natural” approach. But supplements aren’t regulated by the U.S. Food and Drug Administration (FDA), and their manufacturers aren’t supposed to make claims that their products can treat medical conditions. Yet some still do.
“Many supplements on the market merely contain vitamins and minerals, but don’t do anything to improve testosterone,” study co-author Mary K. Samplaski said in a University of Southern California report. “Often, people can be vulnerable to the marketing component of these products, making it difficult to tease out what is myth and what is reality.”
Researchers used the search terms “testosterone booster” and “testosterone supplement” to conduct a Google search of these supplements. They studied the ingredients and manufacturers’ claims for 50 products.
Among all 50 supplements, 109 ingredients were identified, with an average of 8.3 ingredients per product. Zinc, fenugreek, vitamin B6, Tribulus, and Maca extract were some of the most frequently used substances.
Overall, the products made 16 health-benefit claims, such as “improve sleep” and “better mood.” The most common claims were “boost T or free T,” “build body lean mass or muscle mass,” “increase sex drive or libido,” and “feel or be stronger.”
Did the products live up to their promises? It was difficult to tell, since over 60% of the supplements had no scientific research to support their claims. Only 5.5% of the products had more than two medical studies investigating their effects on testosterone.
Available information was conflicting as well. About a quarter of the ingredients had data showing increases in testosterone, and 18% showed no changes in levels. But 10% showed that the supplement deceased testosterone levels.
The researchers also considered the FDA’s Recommended Daily Allowance (RDA) and upper tolerable income level (UL). Some of the ingredients, such as vitamins B12 and B6 were well above recommended amounts. Two of the supplements contained more zinc that the FDA’s UL, which was “worrisome,” the authors noted.
They encouraged patients to be “realistic” with their expectations of supplements.
“Ninety percent of ‘T booster’ supplements claimed to boost T,” they wrote. “However, only 24.8% of these had data to support these claims.”
“Certainly, [testosterone supplementation] is not a substitute for a healthy lifestyle, which is what many of the claims seem to tout,” they added.
University of Southern California
“Are testosterone-boosting supplements effective? Not likely, according to new research”
(June 26, 2019)
The World Journal of Men’s Health
Clemesha, Chase G., et al.
“‘Testosterone Boosting’ Supplements Composition and Claims Are not Supported by the Academic Literature”
(Full-text. Published online: June 14, 2019)