Maca — Lepidium meyenii

Common & Latin Names

Common names: Maca, Peruvian ginseng, Maca root, Maca-maca, Maino, Ayak chichira, Ayak willku Latin name: Lepidium meyenii Walp. (synonym: Lepidium peruvianum Chacon — the synonym is sometimes preferred by Peruvian researchers to distinguish cultivated from wild populations) Quechua: Maca Spanish: Maca, Ginseng andino (Andean ginseng)

Plant Family & Parts Used

Family: Brassicaceae (cruciferous family — related to broccoli, cabbage, turnips, mustard, radish) Parts used: Hypocotyl (the swollen root-like structure that is botanically part root, part stem — often simply called the “root”). The hypocotyl is dried, typically at high altitude in the sun and cold Andean air, then powdered or processed into extracts. Ecotypes: Maca exists in multiple color ecotypes, each with somewhat different phytochemical profiles:

• Yellow maca: Most common (60-70% of harvest). General adaptogen.
• Red maca: Higher in phytochemicals. Favored for prostate health, bone density, and female hormonal support.
• Black maca: Most potent for male fertility, libido, memory, and endurance.
• Purple, pink, cream, and other variants: Less studied but present in traditional use.

Habitat: One of the most extreme-environment medicinal plants on Earth. Endemic to the high-altitude puna and suni ecosystems of the central Peruvian Andes, growing at 3,800-4,500 meters elevation (12,500-14,800 feet) — among the highest-altitude crops in the world. The plant thrives in intense UV radiation, freezing temperatures, strong winds, and poor rocky soil. This extreme environment drives the production of its unique phytochemicals. Currently cultivated primarily in the Junin region of Peru (Lake Junin plateau).

Traditional Uses

Andean Indigenous Medicine (2,000+ years)

Maca has been cultivated in the Andes for at least 2,000 years, with archaeological evidence suggesting even longer use. It held enormous importance in pre-Columbian Andean cultures:

• Fertility and vitality: Inca warriors reportedly consumed large quantities of maca before battle for energy and endurance, but were forbidden from eating it after conquering a city to protect the women from their heightened virility (a frequently cited traditional account recorded by Spanish chroniclers).
• Altitude adaptation: Andean populations consume maca as a daily staple food (not merely as medicine) to support energy, endurance, and adaptation to extreme altitude.
• Livestock fertility: Maca was fed to livestock (particularly llamas and alpacas) to increase fertility and milk production at high altitude — the animal equivalent of its human fertility-enhancing use.
• Food staple: Unlike most medicinal plants, maca is consumed as a significant caloric food — baked, boiled, dried, fermented into maca chicha (a fermented drink), and mixed into porridge. It is a true food-medicine.
• Ceremonial use: Maca played a role in Andean fertility rituals and was offered in ceremonies to Pachamama (Mother Earth) for agricultural abundance and human fertility.

Colonial Period

Spanish conquistadors noted maca’s importance to Andean peoples and reportedly demanded maca as tribute payment. The chronicler Cieza de Leon (1553) recorded that Andean peoples consumed maca for energy and strength. Father Cobo (1653) documented its use for fertility and as a nutritive food.

Modern Western Discovery

Maca remained largely unknown outside the Andes until the 1960s when Gloria Chacon de Popovici (a Peruvian biologist) published the first scientific studies on its effects on fertility in animals. Gustavo Gonzales at Universidad Peruana Cayetano Heredia has been the leading researcher since the late 1990s, producing the clinical evidence that launched maca into global awareness.

Active Compounds & Pharmacology

Primary Phytochemicals

Macamides: Unique to maca — N-benzylamide derivatives of fatty acids not found in any other plant. These include N-benzylhexadecanamide, N-benzyloctadecanamide, and related structures. Macamides inhibit fatty acid amide hydrolase (FAAH), the enzyme that breaks down anandamide (the “bliss molecule”) — the endocannabinoid. This FAAH inhibition may explain maca’s mood-enhancing and sexual function-improving effects.

Macaenes: Unique unsaturated fatty acids found only in maca. Polyunsaturated C16 and C18 acids with unusual structures. Along with macamides, these are the signature compounds distinguishing maca from other cruciferous plants.

Glucosinolates: As a Brassicaceae member, maca contains glucosinolates (including glucotropaeolin and benzyl glucosinolate) that break down into isothiocyanates — the same cancer-protective, detoxification-supporting compounds found in broccoli and other cruciferous vegetables. The glucosinolate profile varies by ecotype.

Alkaloids: Macaridine, lepidiline A and B. Novel alkaloids unique to maca, potentially contributing to neurological and fertility effects.

Sterols: Beta-sitosterol, campesterol, brassicasterol, ergostadienol, stigmasterol. Anti-inflammatory and hormonal-modulating.

Nutritive compounds: 10-14% protein (rich in essential amino acids, particularly arginine and histidine), 59% carbohydrates, 2.2% lipids, fiber, iron, calcium, zinc, copper, manganese, vitamins B1, B2, B12, C, and E. This nutritive density is exceptional for a medicinal plant — it genuinely functions as both food and medicine.

Mechanisms of Action

1. HPG Axis Modulation (Non-Hormonal): Critically, maca does not contain phytoestrogens, phytoandrogens, or any steroidal hormones. Multiple studies have confirmed that maca does not alter serum estradiol, testosterone, FSH, LH, prolactin, or SHBG. Instead, it appears to modulate the hypothalamic-pituitary-gonadal axis at the level of the hypothalamus, optimizing hormonal signaling without directly supplying or mimicking hormones. The mechanism is likely adaptogenic — normalizing HPG output rather than driving it in one direction.

2. FAAH Inhibition (Endocannabinoid Modulation): Macamides inhibit fatty acid amide hydrolase, increasing circulating anandamide. Elevated anandamide improves mood, reduces anxiety, enhances sexual arousal, and modulates pain perception. This mechanism provides a molecular explanation for maca’s effects on sexual desire and emotional well-being.

3. Antioxidant and Neuroprotective: Maca extracts scavenge free radicals, enhance SOD and catalase activity, reduce lipid peroxidation, and protect neurons from oxidative damage. Black maca in particular shows strong neuroprotective and memory-enhancing effects.

4. Bone Density Support: Red maca has demonstrated bone-protective effects in animal models, possibly through modulation of osteoblast/osteoclast balance and calcium metabolism. This is relevant for postmenopausal bone health.

5. Glucosinolate-Mediated Detoxification: The cruciferous glucosinolates in maca support Phase II detoxification enzymes (glutathione transferase, quinone reductase), contributing to cancer-protective and estrogen-metabolizing effects.

Clinical Evidence

Key Clinical Trials

Gonzales, G.F., Cordova, A., Vega, K., et al. (2002). “Effect of Lepidium meyenii (MACA) on sexual desire and its absent relationship with serum testosterone levels in adult healthy men.” Andrologia, 34(6), 367-372.

• 57 healthy men, randomized to maca (1.5g or 3g daily) or placebo for 12 weeks
• Sexual desire improved significantly at 8 weeks (p<0.001) and remained elevated at 12 weeks
• Critically: serum testosterone, estradiol, LH, FSH, and prolactin were NOT affected
• Demonstrated that maca’s effects on libido are not mediated through serum sex hormones
• This study established the “non-hormonal libido enhancement” paradigm for maca

Meissner, H.O., Mscisz, A., Reich-Bilinska, H., et al. (2006). “Hormone-Balancing Effect of Pre-Gelatinized Organic Maca (Lepidium peruvianum Chacon): (III) Clinical responses of early-postmenopausal women to Maca in double-blind, randomized, placebo-controlled, crossover configuration, outpatient study.” International Journal of Biomedical Science, 2(4), 375-394.

• 22 early-postmenopausal women, pre-gelatinized maca (2g/day) vs. placebo, crossover design
• Maca significantly reduced menopausal symptoms including hot flashes, night sweats, and sleep disturbance
• Significant increase in estradiol and decrease in FSH, LH, and ACTH — suggesting maca stimulates endogenous hormone production rather than providing exogenous hormones
• Increased iron and reduced markers of bone resorption
• Demonstrated maca’s potential as a non-hormonal menopause intervention

Gonzales, G.F., Cordova, A., Gonzales, C., et al. (2001). “Lepidium meyenii (Maca) improved semen parameters in adult men.” Asian Journal of Andrology, 3(4), 301-303.

• 9 adult men, maca 1.5-3g daily for 4 months
• Significant increase in sperm count, sperm motility, and seminal volume
• Serum LH, FSH, prolactin, estradiol, and testosterone were unaffected
• Further confirmed the non-hormonal mechanism while demonstrating fertility-enhancing effects

Brooks, N.A., Wilcox, G., Walker, K.Z., et al. (2008). “Beneficial effects of Lepidium meyenii (Maca) on psychological symptoms and measures of sexual dysfunction in postmenopausal women are not related to estrogen or androgen content.” Menopause, 15(6), 1157-1162.

• 14 postmenopausal women, 3.5g maca daily for 6 weeks vs. placebo (crossover)
• Significant reduction in anxiety and depression (p<0.05)
• Significant improvement in sexual dysfunction scores
• Estrogen and androgen levels were not changed — confirming non-hormonal mechanism
• Demonstrated psychological benefits independent of hormonal changes

Gonzales, G.F. (2012). “Ethnobiology and Ethnopharmacology of Lepidium meyenii (Maca), a Plant from the Peruvian Highlands.” Evidence-Based Complementary and Alternative Medicine, 2012, 193496.

• Comprehensive review by the leading maca researcher
• Summarized evidence for fertility enhancement (male and female), sexual desire, energy, mood, menopausal symptom reduction, and neuroprotection
• Confirmed that maca’s effects are NOT mediated through direct hormonal changes
• Proposed that the hypothalamic-level mechanism and FAAH inhibition are the most plausible explanations

Therapeutic Applications

Conditions

• Low libido (men and women): The best-supported indication — multiple RCTs demonstrate improved sexual desire independent of hormone levels
• Male infertility: Improved sperm count, motility, and morphology
• Menopausal symptoms: Hot flashes, night sweats, mood changes — non-hormonal alternative to HRT
• SSRI-induced sexual dysfunction: Preliminary evidence for improving sexual function in patients on antidepressants
• Fatigue and endurance: Traditional use supported by preliminary clinical evidence
• Mood and anxiety: Reduced depression and anxiety in menopausal women (Brooks 2008)
• Memory and cognition: Black maca specifically — animal evidence strong, human evidence emerging
• Bone density support: Red maca — primarily preclinical evidence
• Prostate health: Red maca — preliminary evidence for reducing prostate size

Dosage Ranges

• Gelatinized maca powder (pre-cooked, starch removed — better tolerated): 1.5-3g daily. This is the form most studied clinically and most commonly recommended.
• Raw maca powder: 3-10g daily (higher dose needed due to the presence of raw starch and glucosinolates that may cause GI discomfort). Traditional Andean consumption is 20-100g daily as food.
• Maca extract (concentrated, standardized to macamides/macaenes): 450-1500mg daily
• Color-specific maca: Black maca for male fertility/cognition, Red maca for female hormonal/bone support, Yellow for general adaptogenic use. Combinations of all three colors are popular.

Forms

Gelatinized powder (the starch is pre-cooked, improving digestibility and concentrating active compounds) is the most practical and best-tolerated form. It can be added to smoothies, coffee, oatmeal, or warm drinks. Maca has a malty, slightly nutty, butterscotch-like flavor that blends well with chocolate, banana, and warm beverages. Capsules are convenient for consistent dosing. Effects on libido typically manifest within 2-6 weeks; fertility effects require 3-4 months.

Safety & Contraindications

Exceptionally Well Tolerated

Maca has been consumed as a staple food in the Andes for millennia at doses 10-50x higher than typical supplemental doses. It has one of the safest profiles of any medicinal plant.

Contraindications

• Thyroid conditions: As a cruciferous plant, maca contains goitrogens (glucosinolates) that may theoretically interfere with thyroid function in susceptible individuals. However, gelatinized maca has reduced goitrogen content, and the Meissner (2006) study actually showed improved thyroid function markers. In practice, maca at standard doses is unlikely to affect thyroid function negatively, but monitor in hypothyroid patients on precise thyroid medication dosing.
• Hormone-sensitive conditions (theoretical): Despite containing no phytoestrogens, maca may stimulate endogenous estrogen production (Meissner 2006). Use with caution in estrogen receptor-positive breast cancer until more data is available.
• Pregnancy and lactation: Insufficient clinical data for definitive recommendation. Traditional use by Andean women during pregnancy exists, but clinical trials have not been conducted. Conservative guidance: avoid during pregnancy.

Drug Interactions

• No significant drug interactions have been identified. Maca does not significantly affect CYP450 enzymes in available studies.
• MAOI antidepressants: Theoretical concern based on maca alkaloid content, but no clinical reports of interaction.
• Thyroid medications: Monitor due to glucosinolate content (as with all cruciferous foods in hypothyroid patients).

Side Effects

Very rare at standard doses. Some individuals report GI discomfort with raw maca powder (the raw starch can be difficult to digest — gelatinized form solves this). Insomnia if taken late in the day (some people find maca mildly energizing). Headache reported rarely. Jittery or “wired” feeling at very high doses.

Energetics

TCM Classification (Modern Integration)

• Temperature: Warm
• Flavor: Sweet, slightly pungent
• Meridian entry: Kidney, Liver, Spleen
• Actions: Tonifies Kidney Yang and Kidney Jing, nourishes Essence (Jing), warms the Ming Men (Gate of Vitality), strengthens the Spleen
• TCM pattern correspondence: Kidney Yang deficiency (low libido, fatigue, cold limbs, infertility, low back pain), Kidney Jing deficiency (premature aging, poor memory, infertility, bone weakness), Ming Men fire deficiency (the deepest level of Yang collapse — loss of life force and reproductive capacity)

Ayurvedic Classification

• Rasa (taste): Madhura (sweet), Katu (mildly pungent)
• Virya (energy/potency): Ushna (warming)
• Vipaka (post-digestive effect): Madhura (sweet)
• Dosha effects: Primarily pacifies Vata (grounding, nourishing, warming). Tonifies Kapha in a constructive way (builds tissue). May mildly increase Pitta in excess.
• Dhatu affinity: Shukra (reproductive — primary target), Mamsa (muscle), Asthi (bone), Majja (nerve/marrow), Rasa (plasma)
• Srotas affinity: Shukravaha (reproductive), Mamsavaha (muscular), Asthivaha (bone)
• Comparable Ayurvedic concept: Maca functions as a Vajikara (aphrodisiac) and Balya (strength-promoting) herb, comparable in action to Ashwagandha but with a more direct reproductive focus.

Functional Medicine Integration

Maca occupies a unique niche in functional medicine as a non-hormonal hormonal optimizer — it improves reproductive and sexual function without directly manipulating hormone levels.

Libido and Sexual Function Protocol

For both men and women with low libido, maca is a first-line intervention because it is effective, safe, non-hormonal, and works through a unique mechanism (likely FAAH inhibition/endocannabinoid modulation). It is particularly valuable when low libido persists despite adequate hormone levels — the common clinical scenario where testosterone/estrogen are “normal” but desire is absent.

Male Fertility Protocol

For oligospermia and asthenospermia (low count and poor motility), maca (particularly black maca) at 1.5-3g daily for 3-4 months improves semen parameters. It is combined with zinc, CoQ10, L-carnitine, selenium, and antioxidants in comprehensive male fertility programs.

Menopause Protocol (Non-Hormonal)

For women who cannot or choose not to use hormone replacement therapy, maca provides symptom relief (hot flashes, mood, sexual function) through a non-estrogenic mechanism. It is combined with black cohosh, dong quai, and adaptogenic herbs in comprehensive non-HRT menopause protocols.

Adrenal and Energy Protocol

Maca’s traditional use as an endurance and energy food aligns with its role in functional medicine as a secondary adaptogen — supporting energy and stress resilience. It is often combined with primary adaptogens (ashwagandha, rhodiola, eleuthero) in comprehensive adrenal support programs.

SSRI-Induced Sexual Dysfunction

Sexual dysfunction affects 40-70% of SSRI users and is the leading cause of medication non-compliance. Maca (3g/day) has shown preliminary evidence for improving sexual function in SSRI users without interfering with the antidepressant effect. This application, while still needing larger trials, represents a significant clinical opportunity.

Four Directions Connection

Primary Direction: Serpent (South — Physical Body)

Maca is the Serpent’s food — a root medicine that builds the physical body from its deepest reserves. It grows at the highest altitudes, in the harshest conditions, and it transmits that resilience to the bodies that consume it. The Serpent governs vitality, sexuality, and the raw physical force of the organism. Maca feeds this force at the level of reproductive essence — what TCM calls Jing and Ayurveda calls Shukra. It builds the body’s capacity for creation, endurance, and adaptation to extreme conditions. The Inca warriors who consumed maca before battle knew this — they were feeding the Serpent.

Secondary Direction: Jaguar (West — Emotional Healing)

Maca’s effects on mood, anxiety, and sexual desire connect it to the Jaguar’s emotional domain. Libido is not merely a physical drive — it is an expression of the emotional body’s willingness to connect, to be vulnerable, to merge with another. When libido is suppressed (whether by stress, depression, SSRIs, or hormonal shifts), it reflects an emotional withdrawal — the Jaguar’s territory. Maca’s FAAH-inhibiting, anandamide-raising mechanism literally increases the “bliss molecule,” reopening the emotional body’s willingness to engage with pleasure and connection.

Tertiary: Hummingbird (North — Ancestral Wisdom)

Maca carries the wisdom of the Andean highlands — a civilization that thrived at altitudes where most plants cannot grow. The Quechua and Aymara peoples developed an intimate relationship with this plant over two millennia, understanding its power to sustain life in extreme conditions. The Hummingbird teaches us that the most powerful medicines often come from the harshest places — because the plants that survive extreme environments concentrate the compounds that help us survive extreme stress. Maca is the Hummingbird’s gift from the high mountains.

References

1. Gonzales, G.F., Cordova, A., Vega, K., et al. (2002). Effect of Lepidium meyenii (MACA) on sexual desire and its absent relationship with serum testosterone levels in adult healthy men. Andrologia, 34(6), 367-372.

2. Meissner, H.O., Mscisz, A., Reich-Bilinska, H., et al. (2006). Hormone-Balancing Effect of Pre-Gelatinized Organic Maca (Lepidium peruvianum Chacon): (III) Clinical responses of early-postmenopausal women to Maca. International Journal of Biomedical Science, 2(4), 375-394.

3. Gonzales, G.F., Cordova, A., Gonzales, C., et al. (2001). Lepidium meyenii (Maca) improved semen parameters in adult men. Asian Journal of Andrology, 3(4), 301-303.

4. Brooks, N.A., Wilcox, G., Walker, K.Z., et al. (2008). Beneficial effects of Lepidium meyenii (Maca) on psychological symptoms and measures of sexual dysfunction in postmenopausal women are not related to estrogen or androgen content. Menopause, 15(6), 1157-1162.

5. Gonzales, G.F. (2012). Ethnobiology and Ethnopharmacology of Lepidium meyenii (Maca), a Plant from the Peruvian Highlands. Evidence-Based Complementary and Alternative Medicine, 2012, 193496.

6. Dini, A., Migliuolo, G., Rastrelli, L., Saturnino, P., & Schettino, O. (1994). Chemical composition of Lepidium meyenii. Food Chemistry, 49(4), 347-349.

7. Pino-Figueroa, A., Nguyen, D., & Maher, T.J. (2010). Neuroprotective effects of Lepidium meyenii (Maca). Annals of the New York Academy of Sciences, 1199, 77-85.

8. Gonzales, G.F., Gonzales, C., & Gonzales-Castaneda, C. (2009). Lepidium meyenii (Maca): a plant from the highlands of Peru — from tradition to science. Forschende Komplementarmedizin, 16(6), 373-380.

9. Wu, H., Kelley, C.J., Pino-Figueroa, A., Nguyen, H.D., & Bhatt, T.J. (2013). Macamides and their synthetic analogs: evaluation of in vitro FAAH inhibition. Bioorganic & Medicinal Chemistry, 21(17), 5188-5197.

10. Lee, M.S., Lee, H.W., You, S., & Ha, K.T. (2016). The use of maca (Lepidium meyenii) for health care: an overview of systematic reviews. Maturitas, 92, 64-69.