Maca Root Extract
Lepidium meyenii Walpers (maca) is a Peruvian plant that belongs to the Brassicaceae family (Cruciferae) (1). Maca mainly grows at an altitude of ≥4,000 m in a habitat of intense cold, extremely intense sunlight and strong winds. Maca has been cultivated in the Peruvian central Andes (2). Maca was probably domesticated in present-day Ondores some 1,300–2,000 years ago. Maca is used as a food supplement and for its presumed medicinal properties. Peru’s native population in the central Andes uses the dry hypocotyls in amounts >20 g/d. There are no reports of adverse reactions after consuming Lepidium meyenii in food. Natives from the highlands of Peru recommend that maca be boiled before its consumption (3).
Father Cobo (2) was the first to describe maca and its properties in 1653. He stated that this plant grew in the harshest and coldest areas of the province of Chinchaycocha where no other plant for man’s sustenance could be grown. Cobo also referred to the use of maca for fertility. Traditionally, after being harvested maca is dried naturally and can thus be stored for many years [(3). The dried hypocotyls are hard as stone. Before dried maca can be eaten, the hypocotyls are boiled in water in order to obtain a soft product which can be consumed as juice (3). The effect of temperature affects the availability of several secondary metabolites in plants. Quercetin, for example, is sensitive to temperature. Likewise, the constituents of glucosinolates are sensitive to heating (4). Other metabolites, however, are increased.
Learning and Memory
According to the natives of the highlands, maca is given to children to improve performance in school examinations. Several experimental studies were performed to determine the effects of maca on learning and memory (5-7). In addition, experiments to assess antidepressant and anti-stress effects have been performed (5,8,9). Benefits over memory impairments have been observed in pre-clinical models of Alzheimer disease (10). It is suggested that maca improves experimental memory impairment induced by ovariectomy, partly for its antioxidant and AChE-inhibiting activities (5) and extracts of maca significantly ameliorated scopolamine-induced memory impairment (7). Maca extracts inhibited AChE activity but did not affect MAO activity.
Anxiety and depression
Several clinical trials have assessed the efficacy and safety of maca consumption. Two of them included healthy men (11-13), and four trials included participants with pathological conditions (14-17). In one clinical trial performed in healthy men, using a double-blind placebo-controlled, randomized, parallel-group design, treatment with three different schedules of gelatinized maca was compared with placebo (15 men). Treatment with maca as compared to placebo (18) after 8 weeks of treatment; improved mood and anxiety, and increased activity.
In postmenopausal women, treatment with maca for 6 weeks reduced psychological symptoms including anxiety and depression and reduced measures of sexual dysfunction (15).
Maca has been shown to reduce scores in depression and anxiety inventories, act as an energizer (12,13,15), leaving unaffected serum levels of luteinizing hormone (LH), follicle stimulating hormone (FSH), prolactin, testosterone, and estradiol.
Fatigue
A recent study investigated the anti-physical fatigue effect of polysaccharides from maca (MCP) and the possible mechanisms (19). After the treatment period, the anti-fatigue effects of MCP were evaluated and several biochemical parameters related to physical fatigue were determined: blood lactic acid (BLA), serum urea nitrogen (SUN), glycogen, superoxide dismutase (SOD), glutathione peroxidase (GPx), catalase (CAT), and malondialdehyde (MDA). Results showed that MCP could prolong exercise times, decrease the levels of BLA and SUN, and increase the liver glycogen contents. Furthermore, MCP increased activities of SOD, GPx and CAT, and decreased MDA level. These findings indicate that MCP has obvious anti-physical fatigue effect, and the possible mechanisms were to delay the increase of BLA, reduce the catabolic decomposition of protein for energy and lipid peroxidation, and improve reserve and antioxidant enzymes activities.
References
1. Quiroz C, Aliaga R: Maca (Lepidium meyenii Walp.);in Hermann M, Hellers J (eds): Andean Roots and Tubers: Ahipa, Arracacha, Maca and Yacon. Promoting the Conservation and Use of Underutilized Neglected Crops. 21. Rome, International Plant Genetic Resources Institute, 1997, pp 173–197.
2. Cobo B [1653]: History of the New World. Madrid, Biblioteca de Autores Españoles, 1956.
3. Valerio L, Gonzales GF: Toxicological aspects of South American herbs: Uncaria tomentosa (Cat’s Claw) and Lepidium meyenii (maca). A critical
4. synopsis. Toxicol Rev 2005;24:11–35.
5. Cieza de León P: Chronicle of Peru. First Part. London, Hakluyt Society, 1553.
6. Rubio J, Caldas M, Dávila S, Gasco M, Gonzales GF: Effect of three different cultivars of Lepidium meyenii (maca) on learning and depression in ovariectomized mice. BMC Complement Altern Med 2006; 6:23.
7. Rubio J, Qiong W, Liu X, Jiang Z, Dang H, Chen SL, Gonzales GF: Aqueous extract of black maca (lepidium meyenii) on memory impairment induced by ovariectomy in mice. Evid Based Complement Alternat Med 2008;Oct 9 [Epub ahead of print].
8. Lopez-Fando A, Gomez-Serranillos MP, Iglesias I, Lock O, Upamayta UP, Carretero ME: Lepidium peruvianum chacon restores homeostasis impaired by restraint stress. Phytother Res 2004;18:471–474.
9. Tapia A, López C, Marcelo A, Aguilar JL: The Maca (Lepidium meyenii) and their effect antistress in an animal model in mice [in Spanish]. Acta Andina 2000;8:45–56.
10. Bartus RT: On neurodegenerative diseases, models, and treatment strategies: lessons learned and lessons forgotten a generation following the cholinergic hypothesis. Exp Neurol 2000;163:495–529.
11. Gonzales GF, Córdova A, Vega K, Chung A, Villena A: Effect of Lepidium meyenii (maca), a root with aphrodisiac and fertility-enhancing properties, on serum reproductive hormone levels in adult healthy men. J Endocrinol 2003;176:163–168.
12. Mehta K, Gala J, Bhasale S, Naik S, Modak M, Thakur H, Deo N, Miller MJ: Comparison of glucosamine sulfate and a polyherbal supplement for the relief of osteoarthritis of the knee: a randomized controlled trial [ISRCTN25438351]. BMC Complement Altern Med 2007;7:34.
13. Brooks NA, Wilcox G, Walker KZ, Ashton JF, Cox MB, Stojanovska L: 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 2008;15:1157–1162.
14. Dording CM, Fisher L, Papakostas G, Farabaugh A, Sonawalla S, Fava M, Mischoulon D: A doubleblind, randomized, pilot dose-finding study of maca root (L. meyenii) for the management of SSRIinduced sexual dysfunction. CNS Neurosci Ther 2008;14:182–191.
15. Valentová K, Stejskal D, Bartek J, Dvorácková S, Kren V, Ulrichová J, Simánek V: Maca (Lepidium meyenii) and yacon (Smallanthus sonchifolius) in combination with silymarin as food supplements: in vivo safety assessment. Food Chem Toxicol 2008;46: 1006–1013.
16. Zenico T, Cicero AF, Valmorri L, Mercuriali M, Bercovich E: Subjective effects of Lepidium meyenii (maca) extract on well-being and sexual performances in patients with mild erectile dysfunction: a randomised, double-blind clinical trial. Andrologia 2009;41:95–99.
17. Gonzales GF, Córdova A, Vega K, Chung A, Villena A: Effect of Lepidium meyenii (maca), a root with aphrodisiac and fertility-enhancing properties, on serum reproductive hormone levels in adult healthy men. J Endocrinol 2003;176:163–168.
18. Gonzales GF: Biological effects of Lepidium meyenii, maca, a plant from the highlands of Peru; in Singh VK, Bhardwaj R, Govil JN, Sharma RK (eds): Natural Products. Series: Recent Progress in Medicinal Plants, vol 15. Houston, TX, Studium Press, 2006, pp 217–242.
19. Li RW, He JC, Song DH. Anti-physical fatigue effect of polysaccharides from Lepidium meyenii. Walp. and the possible mechanisms. Biomedical Research. 2017.