Dietary supplements claiming to boost testosterone or
enhance sexual performance are often explored and inquired about by athletes.
However, these products come with concerns. Many of the ingredients are created
in factories, making them unnatural, and lack scientific evidence regarding
their safety and efficacy, even if the products are labeled as “herbal” or “all
natural” (Campbell et al., 2013).
The Food and Drug Administration (FDA) holds dietary
supplement manufacturers responsible for truth in labeling and safety of all
dietary supplement products that enter the consumer market. Unfortunately, these
companies may not list each product ingredient on the supplement facts panel,
can make false or exaggerated claims, and/or add harmful ingredients. Due to
the unregulated nature of supplements, there is little data regarding the products
as a whole, including the ingredients, use of proprietary blends, and marketing
claims (Willoughby, Spillane, & Schwarz, 2014).
Testosterone boosters and sexual enhancement products have a
higher risk of containing harmful ingredients that are not listed on the label,
compared to other supplement categories. For example, phosphodiesterase type 5
(PDE5) inhibitors are pharmaceutical medications used to treat erectile
dysfunction. PDE5 inhibitors have been found in testosterone boosting and
sexual enhancement supplements, but have not been listed on the product label. In
2013, researchers tested sexual performance supplements to determine if they were
adulterated with PDE5 inhibitors or other undeclared ingredients. The marketing for all 54 tested supplements
claimed they did not contain synthetic substances. However, 81% of the tested
products contained one or more synthetic PDE5 inhibitor or similar ingredient, undisclosed
to the consumer (Campbell et al., 2013).
Taking dietary supplements that “boost testosterone” have
proven ineffective in reducing fat mass, as well as increasing total body or
muscle mass. Instead, products making these claims come with a lot of unknowns
and dangers (Willoughby et al., 2014).
Consumers are made to believe that testosterone levels and
muscle mass will increase with the use of dietary supplements claiming to be testosterone
boosters. Manufacturers even state that their product is scientifically proven
to work. When in reality, they often contain dietary ingredients that have not been
tested for efficacy or safety.
Tribulus terrestris (TT) is a popular herbal ingredient
found in testosterone boosting supplements. TT is associated with claims of
boosting testosterone and correcting erectile function. Physically-active men
are the target market for products containing TT (Pokrywka, 2014). Similarly,
TT allegedly improves plasma testosterone levels and increases skeletal muscle
growth (Antonio, Uelmen, Rodriguez, & Earnest, 2000). The use of dietary
supplements with TT has shown no substantiated benefits in human studies. As
with most dietary ingredients, there is a lack of evidence-based information
regarding the effectiveness and safety of TT use in sport (Pokrywka, 2014). The
consumer should be aware that many herbal/all-natural ingredients claiming to
boost testosterone levels or provide other anabolic effects have limited
scientific support.
Drug Free Sport believes that food should be the first
option for fueling when athletes are looking to reach performance goals.
Dietary supplements are poorly regulated by the FDA, with manufacturers loosely
following the FDA’s guidelines. Supplement companies market their products how
they wish, often place unlabeled ingredients in the bottle, and make false
claims. Appropriately-timed meals and snacks, on the other hand, have been proven
to aid in weight reduction and achieving sports performance goals.
If you are thinking about taking any dietary supplement,
please visit
Drug Free Sport AXIS™ to learn more about your options to make an
informed decision.
References:
Antonio, J., Uelmen, J.,
Rodriguez, R., & Earnest, C. (2000). The effects of tribulus terrestris on
body composition and exercise performance in resistance-trained males. International Journal of Sport Nutrition and
Exercise Metabolism, 10, 208-215.
Campbell, N., Clark, J.P.,
Stecher, V.J., Thomas, J.W., Callanan, A.C., Donnelly, B.F.,… Kaminetsky, J.C.
(2013). Adulteration of purported herbal and natural sexual performance
enhancement dietary supplements with synthetic phosphodiesterase type 5
inhibitors. International Society for
Sexual Medicine, 10, 1842-1849.
Pokrywka, A., Obminski, Z.,
Malczewska-Lenczowska, J., Fijatek, Z., Turek-Lepa, E., & Grucza, R.
(2014). Insights into supplements with tribulus terrestris used by athletes. Journal of Human Kinetics, 41, 99-105.
Qureshi, A., Naughton, D.P., &
Petroczi, A. (2014). A systematic review on the herbal extract tribulus
terrestris and the roots of its putative aphrodisiac and performance enhancing
effect. Journal of Dietary Supplements,
11(1), 64-79.
Willoughby, D.S., Spillane, M.,
& Schwarz, N. (2014). Heavy resistance training and supplementation with
the alleged testosterone booster NMDA has on effect on body composition, muscle
performance, and serum hormones associated with the
hypothalamo-pituitary-gonadal axis in resistance-trained males. Journal of Sports Science and Medicine, 13,
192-199.
