Maca (Lepidium meyenii)

Tier 3 — weak evidence · Libido · Energy · Fertility

A Peruvian root vegetable traditionally used for energy and libido. A Shin 2010 systematic review (4 small RCTs, BMC Complement Altern Med) concluded evidence for improved sexual function is limited but suggestive; later small trials report modest libido and energy improvements with no consistent effect on testosterone. NCCIH considers it generally safe for short-term use. The gelatinised form is easier on the stomach. Allow 6–8 weeks.

Dose: 1,500–3,000 mg/day gelatinised maca powder; allow 6–8 weeks for assessment