Tribulus Terrestris

Supplements · Hormone Support · Supplement, Typed Supps

One of the most popular testosterone-booster herbs, on weak evidence.

Stage by stage

Intake (Extract capsule): Active compounds absorbed in the small intestine.
Small intestine (Absorbed): Absorbed alongside other plant compounds.
Bloodstream (Circulates): Circulates throughout the body.
Testosterone & libido (Most trials show no effect): Studied for testosterone and libido, with most controlled trials in healthy men showing no meaningful increase.

What the evidence supports

Raising testosterone — insufficient evidence. Tested repeatedly in men and consistently found to do nothing. This is not an evidence gap — it is a well-replicated negative, and it is the single claim the product is sold on.
Improving athletic performance or body composition — insufficient evidence. Follows from the above. Trials in athletes have found no effect on strength or lean mass.
Improving libido or sexual function — limited evidence. A few small trials, some in women and some in men with erectile dysfunction, report modest effects. This is the least weak claim and it is not the one on the label.

Typical dose

There is no established dose, because there is no established effect on the thing it is sold for. Trials have used roughly 250–1,500 mg daily of extract, most often around 750 mg, for one to three months — and at those amounts repeatedly found no change in testosterone.

Upper limit: No formal upper limit and no long-term safety data. Sleep disturbance, fatigue and raised heart rate have been reported above about 1,000 mg daily

Timing

With food, standard dosing.

Time to effect

Weeks: Most trials show limited hormonal effect regardless of duration.

Medication interactions

Diabetes and blood pressure medication: May add to glucose and blood pressure lowering. (moderate)
Lithium: Possible diuretic effect altering lithium levels. (high)

Common myth

“Tribulus significantly raises testosterone.” In reality: Most controlled human trials in healthy men don’t show a meaningful increase, despite its popularity as a ‘booster.’