Maca
“Lepidium meyenii or Lepidium peruvianum” is a plant related to the cabbage family. It is used as food and medicine in Peru. Lepidium meyenii (Maca) contains several active components, including alkaloids, glucosinolates, isothiocyanates, polysaccharides, polyphenols, and sterols, which make it have the traditional therapeutic uses.
Common Names
- Maca-maca
- Maino
- Ayak chichira
- Ayak willku
Potential uses and benefits
- Improve your energy and strength.
- Increase fertility (the ability to become pregnant with a biological child).
- Improve your desire to have sex.
- Relieve side effects of your period stopping permanently, such as hot flashes.
Purported Use and benefit:
- Stamina
- Infertility
- Libido
- Menopause
Side effects
Side effects have not been reported.
Clinical Summary
Maca is a nutritionally valuable plant native to Peru that grows in harsh climates above 4,000 feet. It has been used traditionally to enhance fertility and sexual performance in both men and women and to relieve menopausal symptoms (1). In vitro, maca or its constituents have demonstrated antiviral (17), antioxidant (18), anti-inflammatory, analgesic, or neuroprotective (19) activities. Animal studies suggest maca may increase endurance (6), enhance sexual function (2)(5), and improve memory deficits (14). It also demonstrated antidepressant (20) and postmenopausal hormone-modulating (21) effects.
Only a few small trials have been conducted in humans. Maca consumption was associated with lower serum IL-6 levels and higher health status (22). In men, preliminary findings suggest supplementation may enhance subjective sexual well-being (11), but data are mixed on whether it can affect various parameters of semen quality (3)(4)(35) or sperm concentration (36). A systematic review determined high dose supplementation to improve antidepressant-induced sexual dysfunction (37). In women, several studies suggest maca improves both antidepressant- and menopause-induced sexual dysfunction (12)(24)(25)(26)(37) although one small study showed neither hormonal nor immunological effects (27). In addition, systematic reviews have deemed evidence for improving sexual dysfunction (13)(28)(29) or menopausal symptoms (15) to be limited. Another review found maca is not an effective anti-aging agent (16).
A case report showed maca may interfere with testosterone immunoassays (30). Although it is unclear the extent to which maca may affect blood hormone levels, patients should discuss any use of this supplement with their physician.
Mechanism of Action
Maca contains glucosinolates, mostly benzyl-glucosinolate, along with hydroxy or methoxylated benzyl derivatives and tryptophan-derived compounds, and depending on the phenotype (red, yellow, purple or black) may be associated with different biological effects (31).
In vitro, both methanolic and aqueous extracts of maca exhibit estrogenic activity (10). A methanol maca extract demonstrated antiviral activity against Flu-A and Flu-B viruses (17). An isolated N‑alkylamide from maca root exerted cannabimimetic actions (32). Maca polysaccharides demonstrated radical scavenging activity (18). Macamides, normally not present in fresh plants but introduced during traditional drying practices (31), are fatty acid amide hydrolase inhibitors that modulate release of neurotransmitters (19). Antidepressant-like effects were associated with activation of both noradrenergic and dopaminergic systems and attenuation of oxidative stress (20).
In animal models, maca powder enhanced serum luteinizing hormone (LH) levels in female rats during the proestrus LH surge in a dose-dependent manner, suggesting it may enhance fertility (33). In postmenopausal models, maca modulates hormone levels particularly by decreasing follicle-stimulating hormone (FSH) levels (21).
In humans, although maca does not affect serum levels of LH, FSH, prolactin, testosterone, or estradiol in men (4)(9), it appears to modulate some hormone levels in women in some studies (24)(26) but not others (25)(27). Increased LH and decreased FSH that corresponded with improved sexual functioning in postmenopausal women are potentially attributed to a negative feedback loop, resulting in increased androgen production (24)(26). It may also exert androgenic effects at the testosterone receptor on target organs without affecting testosterone or gonadotrophin levels (24)(30). At the same time, the benefits of maca for antidepressant-induced sexual dysfunction in women may be more a function of advancing age rather than menopausal status, as there was no correlation with estrogen levels (24).