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New article on reporting side effects of supplements
Just published in The New England Journal of Medicine: A recent article brings up dietary supplement issues you need to be aware of and discusses how dietary supplement side effects could be monitored better. A PDF of the April 3rd article is available free online.

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You are here: Home Dietary Supplements OPSS: Operation Supplement Safety OPSS: Operation Supplement Safety OPSS Frequently Asked Questions (FAQs) What is Tribulus terrestris and why is it found in dietary supplements?

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 (T. terrestris) is a Mediterranean herb that bears a spine-covered fruit. Other names for T. terrestris include puncturevine caltrops, and small caltrops. The leaf, fruit, and root of T. terrestris have been used in the traditional medicines of China and India for centuries.

Tribulus terrestris is touted as being an indirect testosterone “booster.” For this reason, many athletes use T. terrestris to enhance muscle strength and athletic performance. Tribulus terrestris is also used for male impotence and as a treatment for many other conditions. T. terrestris is not a drug, and its mechanism of action, if any, remains unclear. One active component in T. terrestris—protodioscin—purportedly increases levels of hormones, including testosterone, luteinizing hormone, dehydroepiandrosterone (DHEA), and dihydrotestosterone, but the human body lacks the chemicals necessary to convert it. Insufficient data exist on whether T. terrestris increases levels of testosterone in humans, and no definitive scientific evidence shows that taking T. terrestris enhances strength or athletic performance.

Although T. terrestris has a chemical structure similar to that of the hormone DHEA (a precursor to testosterone and estrogen), no literature indicates it will result in a positive test for steroids. Since the findings on T. terrestris are inconclusive, we discourage the use of this and comparable products. Read multi-ingredient product labels carefully too, as T. terrestris is sometimes combined with other ingredients. It is important to note that contamination of dietary supplements with undeclared prohibited substances such as anabolic steroids has been reported, so you may want to read FDA’s "Tainted products marketed as dietary supplements potentially dangerous."