En esa misma pagina que antes te he pasado creo que esta
EDIT: aqui esta
http://wiki.fit/tribulus-terrestris/
En los hombres sanos, la testosterona no se ve influenciada con suplementos de tribulus terrestris. Puede haber un aumento en los hombres infértiles, pero este es débil. No dice que no funcione para todo el mundo.
Pero ademas, si que hay estudios que dicen que lo aumentan, aun que puede ser poco o insignificante. Pero hay otros qe dicdn cosas distintasc)
" In this human study concluded by Antonio et al. Tribulus Terrestris supplementation did increase strength endurance and body composition of resistance trained men when compared to placebo.
However That’s not enough to prove that the herb would increase testosterone levels, as it’s filled with nutrients and phytochemicals that may have a positive effect on body composition and muscle stamina even without a change in hormones."
"Tribulus PLANT will NOT increase Testosterone levels. However, a STANDARDIZED Tribulus Extract containing at least 10% Protodioscin will most definitely increase testosterone production.
Bulgarian Tribulus has been used to effectively increase testosterone levels for decades. In fact, the pharmaceutical company called "Sopharma Bulgaria" launched a huge research project into the herb ALMOST 20 YEARS AGO, and as a consequence of these studies, brought the very first high-grade effective Tribulus preparation to the PHARMACEUTICAL INDUSTRY(and later the supplement market), called "Tribestan". These studies found that Tribulus' active components are steroidal saponins of the furostanol type, isolated from the epigeous part of the Tribulus terrestris L. plant. Therefore, Tribestan was standardized on a base of the predominating compound, protodioscin.
Here are the studies from Sopharma that demonstrate Tribulus(Protodioscin) Increases Testosterone:
TRIBESTAN EFFECT ON THE CONCENTRATION OF SOME HORMONES IN THE SERUM OF HEALTHY SUBJECTS
S. Milanov, A. Maleeva, M. Taskov
RIRR - Radioisotope and Radioimmunological Laboratory, Sofia
Chemical Pharmaceutical Research Institute,
Sofia, Bulgaria"