Tribulus terrestris

Source: U.S. Department of Health & Human Services, National Institutes of Health, Office of Dietary Supplements (2017).


INGREDIENT	Tribulus terrestris Tribulus terrestris is a plant containing compounds that some sellers claim can improve performance by increasing levels of several hormones, including the male hormone testosterone.
DOES IT WORK?	There’s limited research on the use of Tribulus terrestris supplements to increase strength or muscle mass. The few studies investigating it did not find that it had any benefit.

IS IT SAFE?	Tribulus terrestris hasn’t been studied enough to know whether it’s safe. Studies in animals show that high doses can cause heart, liver, and kidney damage.

BOTTOM LINE	There’s no scientific support for taking Tribulus terrestris supplements to improve exercise or athletic performance. Some sports-medicine experts advise against taking any dietary supplements claimed to boost testosterone.

REMARK	Many performance supplements in the marketplace contain more than one ingredient, and ingredients can work differently when they’re combined. Because most ingredient combinations have not been studied, it is not known how effective or safe they are in improving performance.