Muira puama is reputed to enhance erectile function and orgasm in aging men suffering the effects of fatigue or age-related complaints.31 In one study of 262 men suffering from poor sexual desire, more than 60% reported improvements with muira puama. Additionally, more than 50% of the men reported that muira puama improved their ability to attain an erection.39 While muira puama’s mechanism of action remains unknown, it is interesting to note that the plant contains sterols—the building blocks of sex hormones such as testosterone.