Tongkat Ali (Expanded) for Testosterone Support

Research suggests that Eurycoma longifolia (tongkat ali) may support testosterone levels in men, with evidence spanning in vitro studies, animal models, small randomized controlled trials, and at least two systematic reviews and meta-analyses, the majority of which point in a supportive direction. A 2022 meta-analysis found a statistically significant pooled increase in total testosterone in men, including a subgroup of hypogonadal men, while a 2024 systematic review characterized the evidence as mixed overall and noted that findings were most consistent in men with late-onset hypogonadism. Studies have also explored potential mechanisms, including stimulation of Leydig cells, influence on the hypothalamic-pituitary-gonadal axis, and reductions in sex hormone-binding globulin, particularly in older adults. However, several reviewers consistently note that many individual trials are small, short in duration, and methodologically variable, and that larger, well-controlled studies are needed before firm conclusions about clinical efficacy can be drawn.