Benefits
Improved Sexual Function and Libido
Enhances libido and sexual performance in men with mild erectile dysfunction (2.4 g/day, 12 weeks; significant improvement in IIEF-5 scores, p < 0.001). Reduces SSRI-induced sexual dysfunction in women (3.0 g/day, 12 weeks; improved ASEX and MGH-SFQ scores, p < 0.05). Increases sexual desire in male athletes (2 g/day, 14 days; p = 0.03).
Enhanced Male Fertility
Improves sperm concentration, count, and motility in healthy men and those with infertility (2 g/day, 12 weeks; p < 0.05), without altering hormone levels (testosterone, LH, FSH).
Relief of Menopausal Symptoms
Reduces hot flushes, night sweats, depression, and anxiety in peri- and postmenopausal women (3–3.5 g/day, 6–12 weeks; p < 0.001 for Maca-GO®), independent of estrogen changes.
Improved Psychological Well-Being
Decreases depression and anxiety in postmenopausal women (3.5 g/day, 6 weeks; p < 0.05) and in overweight/obese individuals (33.2% anxiety reduction, 29.4% depression reduction, 8 weeks).
Enhanced Physical Performance
Modestly improves cycling performance in trained male athletes (2 g/day, 14 days; 1.84% reduction in 40 km time trial, p = 0.01).
Support for Late-Onset Hypogonadism
Improves sexual function and urination symptoms in men over 40 (12 weeks; significant improvements in IIEF-5 and IPSS scores, p < 0.05).
Mechanism of action
Antioxidant and Anti-Inflammatory Effects
Glucosinolates and flavonoids scavenge free radicals and reduce oxidative stress, which may improve sperm quality, menopausal symptoms, and general cellular health. Glucosinolates (e.g., benzyl glucosinolate) break down into isothiocyanates, which modulate inflammatory pathways like NF-κB, reducing pro-inflammatory cytokines (e.g., IL-6).
Neuroendocrine Modulation (Adaptogenic Properties)
Unique fatty acid derivatives (e.g., N-benzyl-palmitamide) interact with the hypothalamic-pituitary-adrenal (HPA) axis, balancing stress responses and enhancing energy, mood, and libido. They may act as endocannabinoid-like compounds, influencing CB1 receptors to improve psychological well-being.
Spermatogenesis Support
Maca’s alkaloids and amino acids (e.g., arginine) support sperm production and motility, likely by protecting testicular tissue from oxidative damage and enhancing mitochondrial function in sperm cells.
Estrogenic Support in Menopause
While Maca lacks direct estrogenic activity, its metabolites (e.g., via glucosinolate breakdown) may modulate estrogen receptor signaling indirectly, reducing menopausal symptoms like hot flushes and night sweats.
Energy and Performance Enhancement
Polysaccharides and Sterols improve mitochondrial efficiency and glucose metabolism, enhancing physical endurance and reducing fatigue. Beta-sitosterol may support muscle recovery.
Clinical trials
Randomized, double-blind, placebo-controlled trial in Italy in 50 Caucasian men with mild ED receiving maca dry extract (2,400 mg/day) vs placebo for 12 weeks. (Zenico et al. 2009, Andrologia)
50 men with mild ED.
Maca modestly improved IIEF-5 (International Index of Erectile Function) scores and SAT-P (Satisfaction Profile) vs placebo. CRITICAL CONTEXT: PDE5 inhibitors (sildenafil, tadalafil) remain first-line for ED. Maca effects are smaller and more variable; may have role in mild ED or as adjunct.
12-week, double-blind, placebo-controlled trial at Massachusetts General Hospital in 45 women (mean age 42) with SSRI-induced sexual dysfunction. Outcomes: ASEX, MGH SFQ. (Dording et al. 2015, Evid Based Complement Alternat Med)
45 women with SSRI-induced sexual dysfunction.
Maca 3 g/day produced significantly greater improvement in libido and orgasmic function vs placebo. Effects modest but practically meaningful — SSRI-induced sexual dysfunction is a major adherence problem affecting ~50% of users.
Double-blind, randomized, pilot dose-finding study in 20 remitted depressed outpatients (17 women, mean age 36). (Dording et al. 2008, CNS Neurosci Ther)
20 remitted depressed outpatients on SSRIs.
Higher-dose maca (3 g/day) showed greater benefit on sexual function than lower doses. Established dose ranging for subsequent maca trials.
Systematic review of 4 randomized controlled trials assessing maca for menopausal symptoms in postmenopausal women. (Lee et al. 2011, Maturitas)
Pooled across 4 RCTs.
Modest reductions in menopausal symptoms vs placebo across trials. Effect sizes small. Trial quality variable. Note: hormone therapy remains first-line for moderate-to-severe menopausal symptoms; maca is a modest non-hormonal option.
12-week, double-blind, placebo-controlled trial in Peru in men with infertility receiving 2 g/day maca. Outcomes: sperm parameters, hormones. (2021)
Men with infertility.
Modest improvements in some sperm parameters vs placebo. Note: male infertility evaluation should always include reproductive endocrinology consultation; supplements are adjunctive at best.
14-day, placebo-controlled crossover study at Northumbria University in 8 trained male cyclists receiving maca extract. (Stone et al. 2009, J Ethnopharmacol)
8 trained male cyclists. Crossover.
Modest improvements in 40 km cycling time trial performance vs placebo. CRITICAL CAVEAT: very small sample (n=8), single trial; not robust evidence for athletic performance claims.
12-week, randomized, double-blind, placebo-controlled trial in Korea in 80 eugonadal men aged >40. Outcomes: AMS scores, sexual function, testosterone. (2023)
80 eugonadal men >40.
Modest improvements in some symptom scores; minimal testosterone effect. Note: maca is NOT a meaningful testosterone booster — multiple trials confirm minimal hormonal effects despite popular framing.
6-week, double-blind, placebo-controlled trial in 14 postmenopausal women receiving 3.5 g/day maca. Outcomes: GCS (Greene Climacteric Scale), HAM-A, HAM-D. (Brooks et al. 2008, Menopause)
14 postmenopausal women. Very small.
Modest reductions in anxiety and depression scores vs placebo. CRITICAL CAVEAT: very small trial (n=14); cannot establish meaningful efficacy.