This study conducted for 4 weeks showed that Tribulus terrestris didn't increase testosterone levels above normal range in men.
The aphrodisiac herb Tribulus terrestris does not influence the androgen production in young men
October 2005
Vladimir Neychev
Abstract
The aim of the current study is to investigate the influence of Tribulus terrestris extract on androgen metabolism in young males. Twenty-one healthy young 20-36 years old men with body weight ranging from 60 to 125 kg were randomly separated into three groups-two experimental (each n=7) and a control (placebo) one (n=7). The experimental groups were named TT1 and TT2 and the subjects were assigned to consume 20 and 10 mg/kg body weight per day of Tribulus terrestris extract, respectively, separated into three daily intakes for 4 weeks. Testosterone, androstenedione and luteinizing hormone levels in the serum were measured 24 h before supplementation (clear probe), and at 24, 72, 240, 408 and 576 h from the beginning of the supplementation. There was no significant difference between Tribulus terrestris supplemented groups and controls in the serum testosterone (TT1 (mean+/-S.D.: 15.75+/-1.75 nmol/l); TT2 (mean+/-S.D.: 16.32+/-1.57 nmol/l); controls (mean+/-S.D.: 17.74+/-1.09 nmol/l) (p>0.05)), androstenedione (TT1 (mean+/-S.D.: 1.927+/-0.126 ng/ml); TT2 (mean+/-S.D.: 2.026+/-0.256 ng/ml); controls (mean+/-S.D.: 1.952+/-0.236 ng/ml) (p>0.05)) or luteinizing hormone (TT1 (mean+/-S.D.: 4.662+/-0.274U/l); TT2 (mean+/-S.D.: 4.103+/-0.869U/l); controls (mean+/-S.D.: 4.170+/-0.406U/l) (p>0.05)) levels. All results were within the normal range. The findings in the current study anticipate that Tribulus terrestris steroid saponins possess neither direct nor indirect androgen-increasing properties. The study will be extended in the clarifying the probable mode of action of Tribulus terrestris steroid saponins.