Abstract
Maca (Lepidium meyenii) has been reported to improve erectile function (EF). The purpose of this study was to evaluate the clinical evidence for or against maca as a therapy for erectile dysfunction (ED) in men. We searched 11 databases for randomized controlled trials (RCTs) comparing any type of maca with a placebo in the treatment of ED in men. The primary endpoint was EF, while the secondary endpoints were quality of life and adverse events. Risk of bias (ROB) was assessed using the Cochrane ROB tool 2.0. Study selection, data extraction, and assessment were independently performed by two researchers. RevMan 5.4.1 software (Cochrane Collaboration, 2020) was used for data aggregation, and the Grades of Recommendation, Assessment, Development and Evaluation (GRADE) assessment was used to evaluate the quality of the study outcomes. Only two RCTs met all the inclusion criteria. These RCTs examined the effects of maca on EF in patients with mild ED. One RCT showed a positive effect of maca on EF, whereas the other RCT did not. The results of the meta-analysis indicate that maca has positive effects on EF in men with mild ED (n = 79, MDs 1.13: 0.64 to 1.61, p = 0.01; p < 0.0001). Our comprehensive review found limited evidence for the benefits of maca in improving EF. Several limitations, including the total number of studies and their sample sizes, were insufficient to draw firm conclusions. Further studies are needed.