Maca (Lepidium meyenii)

Category

Herbs & Supplements

Synonyms

Acyclic keto acid, alkaloids, amino, Andean Viagra®, anthocyanines, aromatic glucosinolates, ayak chichira (Quechua/Spanish), ayuk willku (Quechua/Spanish), benzaldehyde, benzyl glucosinolate (glucotropaeolin), beta-ecdysone, Brassicaceae (family), calcium, carboline, cardiotonic glycosides, campesterol, chicha de maca (Spanish), Cruciferae (former family name), fatty acids, flavonoids, glucosinolate degradation products, glucotropaeolin, imidazole alkaloids, iron, isopteropodin, Lepidieae (tribe), lepidiline A, lepidiline B, Lepidium apetalum, Lepidium meyenii, Lepidium peruvianum Chacón, Lepidium sativum L., maca chicha, maca maca, macaenes, macamides, macaridine, mace, magnesium, maino, maka, malic acid, matia, methoxybenzyl isothiocyanate, natural Viagra®, pepperweed, Peruvian ginseng, Peruvian maca, phenyl acetonitrile, phosphorus, potassium, prostaglandins, protein, quercitin, saponins, sitosterols, steroids, stigmasterol, tannins, uridine, vitamin B1, vitamin B12, vitamin C, vitamin E, vitamin K, zinc.

Background

Maca is a vegetable that has been cultivated as a root crop for at least 2,000 years. It can be found wild in Peru, Bolivia, Paraguay, and Argentina, but has primarily been cultivated in the highlands of the Peruvian Andes. Because of its ability to grow in harsh climates at high-altitude, maca is an important staple food for native populations in the Peruvian highlands. It is highly nutritious with about 11% protein content and can be baked, roasted, prepared as a porridge, and has been used for making a fermented drink.

Traditionally, maca has also been used to relieve stress, as an aphrodisiac, and for fertility enhancement in both males and females. Recently, commercial maca products have gained popularity in areas outside of South America as dietary supplements, with claims of boosting energy, enhancing fertility, balancing hormones, acting as an aphrodisiac, and enhancing sexual performance. However, evidence to support these claims is weak.

Natives of the central Andes do not use fresh maca. It is considered harmful. When maca is harvested, the roots are dried by exposing them to sunlight for 4-6 days. After they have been dried, they can be stored in cool, dark places for several years. For consumption, the dried roots are rehydrated by boiling them in water until they are soft. Maca is also referred to as Peruvian ginseng, although it is not closely related to ginseng.

Evidence

DISCLAIMER: These uses have been tested in humans or animals. Safety and effectiveness have not always been proven. Some of these conditions are potentially serious, and should be evaluated by a qualified healthcare provider.

Aphrodisiac (male): Traditionally in Peru, maca has been used as an aphrodisiac. Maca could improve sexual desire in healthy men independent of changes in mood, or serum testosterone, and estradiol levels. Higher quality studies are needed in this area, in both men and women.
Grade: C

Hormone regulation (male): Traditionally, maca has been used in Peru to enhance fertility. One study did not demonstrate that maca ingestion could change levels of luteinizing hormone, follicle-stimulating hormone, prolactin, hydroxyprogesterone, testosterone, or estradiol. Additional study is needed before a firm conclusion can be made.
Grade: C

Spermatogenesis: Maca has been traditionally used in Peru to enhance fertility of both people and animals. Maca may improve semen quality, however, additional study is needed to confirm this finding.
Grade: C

Tradition

WARNING: DISCLAIMER: The below uses are based on tradition, scientific theories, or limited research. They often have not been thoroughly tested in humans, and safety and effectiveness have not always been proven. Some of these conditions are potentially serious, and should be evaluated by a qualified healthcare provider. There may be other proposed uses that are not listed below.
Adaptogen, AIDS, anabolic, anemia, anxiety, aphrodisiac (female), athletic performance, cancer, chronic fatigue syndrome, cognitive function, depression, fertility, food uses, hepatoprotection, hormonal imbalances (female), immunostimulant, joint diseases, leukemia, menstrual irregularities, metabolic enhancement, nutritional supplement, osteoporosis (postmenopausal), prostate enlargement, sexual function, sexual performance, stimulant, tonic, tuberculosis.

Dosing

Adults (18 years and older):

Maca is likely safe when consumed by healthy adults in doses of 1,500-3,000 milligrams per day for up to four months as an aphrodisiac or to improve spermatogenisis, however, there is no proven effective dose for maca. Traditionally, up to 6,000 milligrams or more per day in divided doses has been used. Root powder containing 2,800 milligrams of maca root placed in 8 ounces of water has also been used up to three times daily. Commercially prepared concentrated extracts containing 450 milligrams taken twice daily has been used as well.

Common dietary consumption in native populations is greater than 100 grams, or equivalent to greater than 1.4g per kilogram, daily.

Children (younger than 18 years):

There is no proven safe or effective dose of maca, and use in children is not recommended.

Safety

DISCLAIMER: Many complementary techniques are practiced by healthcare professionals with formal training, in accordance with the standards of national organizations. However, this is not universally the case, and adverse effects are possible. Due to limited research, in some cases only limited safety information is available.

Allergies

Avoid in individuals with a known allergy or hypersensitivity to maca (Lepidium meyenii).

Side Effects and Warnings

Available studies in humans have only been performed on male subjects. In these trials, no side effects were noted and maca was generally considered safe. Maca has not been studied in women.

Maca may cause changes in some sex hormones, although animal studies have demonstrated conflicting results. Preliminary evidence from studies in humans has failed to show that maca induces changes in luteinizing hormone, follicle stimulating hormone, prolactin, testosterone, and estradiol. However, use cautiously in patients with hormone responsive cancers such as breast cancer, or prostate cancer, and patients who are using birth control pills due to the potential effects of maca on sex hormone regulation.

Consumption of large amounts of maca may cause bloating and flatulence. Consumption of fresh maca may cause stomach pain.

The use of maca may increase leukocytes. The use of maca may decrease PT/INR values in patients being monitored for anticoagulation therapy.

Maca may also lead to stimulation of the central nervous system. Use cautiously in patients with hypertension (high blood pressure), due to the possibility of central nervous system stimulation.

Pregnancy and Breastfeeding

Maca is not recommended in pregnant or breastfeeding women due to a lack of available scientific evidence.

Interactions

Interactions with Drugs

Plants in the Brassicaceae family, such as maca, are often rich in vitamin K. Thus, maca may increase the risk of bleeding when taken with drugs that increase the risk of bleeding. Some examples include aspirin, anticoagulants ("blood thinners") such as warfarin (Coumadin®) or heparin, anti-platelet drugs such as clopidogrel (Plavix®), and non-steroidal anti-inflammatory drugs such as ibuprofen (Motrin®, Advil®) or naproxen (Naprosyn®, Aleve®).

Maca may act as a stimulant and cause hypertension (high blood pressure). Patients taking medication for high blood pressure, or those taking other stimulant medications, should consult with a qualified healthcare professional, including a pharmacist, before combining therapies.

Maca may alter the levels of sex hormones, and may interfere with the effects of hormone replacement therapy or birth control pills. Caution is advised.

Interactions with Herbs and Dietary Supplements

Plants in the Brassicaceae family, such as maca, are often rich in vitamin K. Maca may increase the risk of bleeding when taken with herbs and supplements that are believed to increase the risk of bleeding. Multiple cases of bleeding have been reported with the use of Ginkgo biloba, and fewer cases with garlic and saw palmetto. Numerous other agents may theoretically increase the risk of bleeding, although this has not been proven in most cases

Maca may act as a stimulant and cause hypertension (high blood pressure). Patients taking herbs or supplements for high blood pressure, or those taking other stimulants, should consult with a qualified healthcare professional, including a pharmacist, before combining therapies.

Maca may alter the levels of sex hormones, and may interfere with the effects of herbs or supplements with hormone effects, such as St. John's wort or chasteberry.

Attribution

This information is based on a systematic review of scientific literature, and was peer-reviewed and edited by contributors to the Natural Standard Research Collaboration (www.naturalstandard.com): Molly Davis, PharmD (University of Rhode Island); Nicole Giese, MS (Natural Standard Research Collaboration); Michael Rotblatt, MD, PharmD (UCLA); Toni Schaeffer, PhD, PharmD (Albany College of Pharmacy); Shaina Tanguay-Colucci, BS (Natural Standard Research Collaboration); Ruslan Voloshin, PharmD (Massachusetts College of Pharmacy); Wendy Weissner, BA (Natural Standard Research Collaboration).

Bibliography

DISCLAIMER: Natural Standard developed the above evidence-based information based on a thorough systematic review of the available scientific articles. For comprehensive information about alternative and complementary therapies on the professional level, go to www.naturalstandard.com. Selected references are listed below.

Bogani P, Simonini F, Iriti M, et al. Lepidium meyenii (Maca) does not exert direct androgenic activities. J Ethnopharmacol 4-6-2006;104(3):415-417.

Bustos-Obregon E, Yucra S, Gonzales GF. Lepidium meyenii (Maca) reduces spermatogenic damage induced by a single dose of malathion in mice. Asian J Androl 2005;7(1):71-76.

Chung F, Rubio J, Gonzales C, et al. Dose-response effects of Lepidium meyenii (Maca) aqueous extract on testicular function and weight of different organs in adult rats. J Ethnopharmacol. 4-8-2005;98(1-2):143-147.

Gonzales C, Rubio J, Gasco M, et al. Effect of short-term and long-term treatments with three ecotypes of Lepidium meyenii (MACA) on spermatogenesis in rats. J Ethnopharmacol 2-20-2006;103(3):448-454.

Gonzales GF, Miranda S, Nieto J, et al. Red maca (Lepidium meyenii) reduced prostate size in rats. Reprod.Biol Endocrinol 1-20-2005;3(1):5.

McCollom MM, Villinski JR, McPhail KL, et al. Analysis of macamides in samples of Maca (Lepidium meyenii) by HPLC-UV-MS/MS. Phytochem.Anal. 2005;16(6):463-469.

McKay D. Nutrients and botanicals for erectile dysfunction: examining the evidence. Altern Med Rev 2004;9(1):4-16.

Miller MJ, Ahmed S, Bobrowski P, et al. The chrondoprotective actions of a natural product are associated with the activation of IGF-1 production by human chondrocytes despite the presence of IL-1beta. BMC.Complement Altern Med 2006;6:13.

Rubio J, Caldas M, Davila S, et al. Effect of three different cultivars of Lepidium meyenii (Maca) on learning and depression in ovariectomized mice. BMC.Complement Altern Med 6-23-2006;6(1):23.

Rubio J, Riqueros, MI, Gasco M, et al. Lepidium meyenii (Maca) reversed the lead acetate induced-Damage on reproductive function in male rats. Food Chem Toxicol 2006;44(7):1114-1122.

Ruiz-Luna AC, Salazar S, Aspajo NJ, et al. Lepidium meyenii (Maca) increases litter size in normal adult female mice. Reprod.Biol Endocrinol 5-3-2005;3(1):16.

Valentova K, Buckiova D, Kren V, et al. The in vitro biological activity of Lepidium meyenii extracts. Cell Biol Toxicol 2006;22(2):91-99.

Valerio LG Jr, Gonzales GF. Toxicological aspects of the South American herbs cat's claw (Uncaria tomentosa) and Maca (Lepidium meyenii) : a critical synopsis. Toxicol.Rev 2005;24(1):11-35.

Zhang Y, Yu L, Ao M, et al. Effect of ethanol extract of Lepidium meyenii Walp. on osteoporosis in ovariectomized rat. J Ethnopharmacol 4-21-2006;105(1-2):274-279.

Zhao J, Muhammad I, Dunbar DC, et al. New alkamides from maca (Lepidium meyenii). J Agric.Food Chem. 2-9-2005;53(3):690-693.

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.