Maca (Lepidium) — The Andean Adaptogen

The precise molecular mechanisms of Maca in humans remain poorly characterised. Preclinical models suggest its active compounds, including macamides and macaenes, may exert neuroprotective effects by modulating the endocannabinoid system and reducing oxidative stress. It is also hypothesised to influence the hypothalamic-pituitary-adrenal (HPA) axis, thereby improving stress resilience and energy metabolism without directly altering serum testosterone or estrogen levels. Additionally, Maca extracts have demonstrated antioxidant properties, potentially mitigating mitochondrial dysfunction and cellular senescence.

No published human longevity trials exist. Human evidence for Maca primarily focuses on sexual function, menopausal symptoms, and subjective well-being. A 12-week randomised, double-blind, placebo-controlled trial in men with mild erectile dysfunction showed significant improvements in subjective perception of general and sexual well-being (Zenico et al., 2009). Another 12-week trial in patients with late-onset hypogonadism symptoms demonstrated improvements in Aging Males' Symptoms scale and erectile function (Shin et al., 2023).

1,500–3,000 mg/day of dried Maca root powder or gelatinised extract is the most studied range in humans, typically divided into two or three doses. It is generally taken orally, often with meals. Optimal dosing for specific longevity or healthspan outcomes remains unestablished.

Maca is generally well-tolerated with a safety profile comparable to other dietary vegetables. Mild adverse effects such as gastrointestinal upset or insomnia are occasionally reported. Due to its potential influence on hormonal pathways, individuals with hormone-sensitive conditions (e.g., breast cancer, endometriosis) should exercise caution. Long-term safety data in high doses are lacking.

Key Papers