Evidence Level
The evidence base for Fadogia agrestis is extremely limited. Yakubu et al. (2005) published the primary study, administering aqueous stem extract to male Wistar rats at 18, 50, and 100 mg/kg body weight for 5 days. The extract produced dose-dependent increases in serum testosterone and pro-sexual behavioral changes. However, the same research group published a follow-up study (Yakubu et al., 2008) showing significant dose-dependent testicular toxicity, including damage to seminiferous tubules and interstitial tissue at 100 mg/kg. These findings raise serious safety concerns that remain unresolved due to the complete absence of human clinical trials. The supplement gained popularity through social media and podcast discussions (notably Huberman Lab) rather than through clinical evidence, and the gap between consumer enthusiasm and scientific evidence is among the largest in the supplement industry.