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What is Tribulus terrestris and why is it found in dietary supplements?


What is Tribulus terrestris and why is it found in dietary supplements?

OPSS Answer

Tribulus terrestris is an herb also known as puncturevine caltrops or small caltrops. Its leaves, fruit, and root have been used in the traditional medicines of China and India for centuries.

It is now used as a “testosterone booster” because it has a chemical structure similar to a known hormone (DHEA) involved in testosterone and estrogen production in the human body. For this reason, testosterone booster products with Tribulus terrestris are marketed for sexual enhancement and athletic performance. One component—protodioscin—purportedly increases levels of some hormones, including testosterone and dehydroepiandrosterone (DHEA), but the human body lacks the chemicals necessary to convert it.

There are little or no reliable data regarding the ability of Tribulus terrestris to increase testosterone levels in humans or enhance strength or athletic performance. And despite the chemical similarity to DHEA, there is no literature to indicate that Tribulus terrestris will result in a positive test for steroids. But since the findings on this ingredient are inconclusive, we discourage its use. Note too that the types of dietary supplement products in which Tribulus terrestris is found are the types often contaminated with undeclared drugs or controlled substances such as anabolic steroids; read FDA’s “Tainted Products Marketed as Dietary Supplements” for more information.

FAQ updated 10 May 2014