How Does Tongkat Ali Affect Testosterone?

The video works through the mechanism that sits underneath most tongkat ali marketing and is rarely explained in it. The relevant compounds are quassinoids, a class of molecules concentrated in the root, of which the best characterised is eurycomanone. Eurycomanone is the compound the proposed effects are attributed to, and it is the reason "tongkat ali" on a label tells you almost nothing on its own.

Three mechanisms get covered. The first is aromatase inhibition: aromatase is the enzyme that converts testosterone into estradiol, and eurycomanone has been shown to inhibit it, which would leave more testosterone in circulation and less converted. The second is the SHBG route, the same one Huberman describes, where testosterone bound to sex hormone-binding globulin is released into the free, biologically active fraction. The third is an effect on testosterone synthesis in the Leydig cells of the testes. The video presents these as a package, which is how most consumer content presents them. The honest qualifier, and the one worth carrying on this page, is that the aromatase and Leydig cell findings come largely from cell and animal work rather than from human trials, while the SHBG and free testosterone effects have more human data behind them.