Related Terms

• 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.

Scientific Evidence

Tradition/Theory

The below uses are based on tradition or scientific theories. 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 health care professional.

• 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

The below doses are based on scientific research, publications, traditional use, or expert opinion. Many herbs and supplements have not been thoroughly tested, and safety and effectiveness may not be proven. Brands may be made differently, with variable ingredients, even within the same brand. The below doses may not apply to all products. You should read product labels, and discuss doses with a qualified healthcare provider before starting therapy.

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

The U.S. Food and Drug Administration does not strictly regulate herbs and supplements. There is no guarantee of strength, purity or safety of products, and effects may vary. You should always read product labels. If you have a medical condition, or are taking other drugs, herbs, or supplements, you should speak with a qualified healthcare provider before starting a new therapy. Consult a healthcare provider immediately if you experience side effects.

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

Most herbs and supplements have not been thoroughly tested for interactions with other herbs, supplements, drugs, or foods. The interactions listed below are based on reports in scientific publications, laboratory experiments, or traditional use. You should always read product labels. If you have a medical condition, or are taking other drugs, herbs, or supplements, you should speak with a qualified healthcare provider before starting a new therapy.

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.

Author Information

• This information is based on a systematic review of scientific literature edited and peer-reviewed by contributors to the Natural Standard Research Collaboration (www.naturalstandard.com).

References

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.

1. 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. View Abstract

2. 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. View Abstract

3. 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. View Abstract

4. 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. View Abstract

5. 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. View Abstract

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9. 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. View Abstract

10. 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. View Abstract

11. 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. View Abstract

12. 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. View Abstract

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14. 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. View Abstract

15. 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. View Abstract