In Vitro studies with Tongkat Ali showed a 440% increase in testosterone. In human studies, analysis of the DHEA showed gradual increase in the level from 26% after 1 week to 47% in 3 weeks. SHBG analysis showed decrease in level from 36% after 1 week to 66% after 3 weeks. Consequently, when the SHBG level declines, the Free Testosterone Index goes up in most subjects. This increase in Free Testosterone indicates that it has a bio-stimulatory effect on steroidogensis, meaning that Long jack has the ability to enhance testosterone biosynthesis. Studies done by the department of Pharmacognosy, Tokyo College of Pharmacy & the Faculty of Medicine, Tokyo University, Japan, found anti-cancer properties by isolating anti-leukemia activities of compounds from the plant.





