Maca

A nutritionally valuable plant native to Peru that grows in a harsh climate above 4,000 feet, maca has been used traditionally to enhance fertility and sexual performance in both men and women and to relieve menopausal symptoms ⁽¹⁾. It has been purported to treat cancer and to improve stamina in cancer patients.
Animal studies indicate that maca increases endurance ⁽⁶⁾, enhances sexual function ⁽²⁾⁽⁵⁾ and improves scopolamine-induced memory deficits ⁽¹⁴⁾.

Human trials of maca reported increased libido ⁽³⁾ and improvement in sperm production and sperm motility ⁽⁴⁾. Maca supplementation was also shown to enhance the subjective feeling of sexual well-being ⁽¹¹⁾ and may benefit those with sexual dysfunction induced by selective-serotonin reuptake inhibitors (SSRIs) ⁽¹²⁾. However, the evidence to support use of maca for sexual dysfunction is limited and needs further research ⁽¹³⁾. The data on maca's role in alleviating menopausal symptoms are limited ⁽¹⁵⁾.
Another review indicates that maca is not an effective anti-aging agent ⁽¹⁶⁾.

Dried maca was shown to have lower content of the suspected active metabolite than fresh maca. It is also available as a liquor, tonic and mayonnaise, although health benefits of these derivatives seem minimal ⁽⁷⁾.