By Corey B. Schuler, MS, DC, CNS, LN and Peter Bablis D.C., N.D., LAc, PhD
Maca is an adaptogenic herb cultivated exclusively in the central Peruvian Andes at 12-14,000 feet under harsh natural growing and weather conditions. Adaptogens are an extremely rare class of herb that modulates the body’s response by supporting systems within the body to deal with stress, anxiety and fatigue. So rare, in fact, that Russian researchers studying the mode of action of over 4000 plants found only 12 true adaptogens amongst them. Other common adaptogenic plants include ginseng, ashwagandha, eleuthero, Holy basil, licorice, rhodiola and schisandra. It is important to point out that much of the research appears to demonstrate that adaptogens actually only impact the adrenal glands, thus the increase in energy and improvement in dealing with stress regulating cortisol as an example. However, at no point in the definition of an adaptogen do balancing hormones, increases in bone density, cardiovascular disease, sexual function or many other areas of health actually get mentioned. These statements have been added since, by companies trying to sell products, or mistakenly added to all adaptogens when in fact research into only one herb (which happens to be an adaptogen) may have demonstrated one of these particular benefits.
This is what makes adaptogens so interesting, while they all improve our body’s ability to deal with stress, anxiety and fatigue some have other benefits, maca appears to potentially do the most of all. Which is why many scientists and doctors were not surprised when research over the last decade actually demonstrated that there are many different phenotypes of maca (Phenotype: the observable physical or biochemical characteristics of an organism, as determined by both genetic makeup and environmental influences) that have different physiological effects on the body.
Maca has a wide range of active constituents including amino acids, glucosinolates, phytosterols, and alkaloids. But rather than trying to break down and standardize individual active constituents within maca, it is more interesting to investigate the full spectrum of active constituents of specific phenotypes and the natural synergies of all the active constituents that exist in the individual phenotype. Research has demonstrated that there are in fact 13 different phenotypes within the species Lepidium peruvianum (maca) that exhibit different colors, have different DNA, different analytical profiles and even in some cases elicit different physiological effects on the body.
The Importance of the Phenotypes of Maca
Dr. Gustavo F. Gonzales from the Universidad Peruana Cayetano Heredia in Lima, Peru has published some very interesting research regarding different maca phenotypes in relation to men’s health1. As an example, his research has demonstrated that while the red maca phenotype will reduce the size of a prostate2, other phenotypes won’t, or may even increase the size, while black maca is considered the strongest in energy-promoting properties3. Further discoveries by this group show how black and red maca improve bone health, but yellow did not and that black maca is best for influencing memory and learning.4,5 Exploration of the differences of concentration of active constituents among the different
phenotypes was performed by Clement and revealed that “Colour type has to be considered in maca production, as colour associates with variations in concentrations of distinct bioactive metabolites.”6
In addition, Dr. Henry Meissner has published some potentially ground breaking papers on specific, concentrated maca phenotype combinations. Known as Maca-GO®, these concentrated combinations specifically affect hormone levels in peri and post menopausal women and are to date the only clinical trials on any maca product to demonstrate statistically significant effects on hormones. 7,8 In fact all other studies by Brooks, Oshima, and Mazaro-Costa on normal maca powders or gelatinized maca have shown no statistically significant effect on hormones in peri or post menopausal women or models.9,10,11 In the double blind, placebo crossover human trials conducted by Meissner, he found that specific phenotype combinations and concentrated levels of all the active ingredients are critical to ensuring actual, measurable physiological effects on hormones, lipids and bone density.12,13
Meissner’s research has further evolved this concept of different phenotypes by introducing three concentrated phenotype combination products for women depending on their stage of life. The Maca-GO® phenotype combination is designed to improve a post menopausal women’s hormone production. This combination has resulted in statistically significant increases in estradiol (P<0.001), increases in progesterone and reductions in FSH (P<0.05), with highly significant reductions in menopausal symptoms as well as increases in HDL “good cholesterol”, reductions in LDL “bad cholesterol”, triglycerides and body weight as well as increases in bone density.14 Further phenotype blending using Maca-GO® as a base has been used to reduce menopausal symptoms and modulate mood associated with peri menopause and the fluctuation of hormones during this stage of life as well as for younger women to address hormone imbalance around a wide variety of conditions such as PMS and fertility.15,16,17,18
Another factor in relation to maca is the bioavailability and concentration of the active ingredients required to elicit physiological effects.7,8,19 Quality of seed sources and soil content, as well as organic or biodynamic growing strategies and drying methods, all play a part in maximizing the quality of all active constituents. Interestingly, the higher elevation, region-specific quality soil (not necessarily from certain regions of the depleted Junin Plateau), and traditional sun-drying the crop at elevation over a period of three months (not in tobacco dryers in Lima), have all been shown to contribute to the highest quality raw material. For example, published evidence suggests planting site is a major determining factor with regards to constituents of maca.20 In relation to manufacturing, maca is a tuber and is naturally hard to digest raw. For that reason the native Peruvians traditionally cooked maca the same way we would a potato. Scientifically this process of improving bioavailability has been addressed through gelatinization, with Meissner and La Molina University being the leaders in developing their own processes. Raw maca has a natural water solubility of 68% with gelatinized macas ranging from 87-97% while Meissner has perfected the process to such a degree that Maca-GO® is 99% water soluble.7
As the natural products industry continues to evolve, it is critical that we combine the best of traditional knowledge, organic and biodynamic-type farming practices with the highest levels of science, manufacturing and quality control. All herbs are not created equal therefore it is important to investigate them in detail, support their use with pharmacology, toxicology and human placebo controlled clinical trials and use efficacious products with therapeutic levels that elicit real health benefits.
1 Winston D, et al. Adaptogens. Herbs for Strength, Stamina, and Stress Relief. Healing Arts Press 2007
2 Gonzales GF, et al. Red Maca (Lepidium meyenii) reduced prostate size in rats. Reproductive Biology and Endocrinology 2005, 3(5) 14
3 Skyfield Tropical: Free Online Botanical Encyclopedia Maca (lepidium peruvianum): Botanical Characteristics
4 Gonzales C, Cárdenas-Valencia I, Leiva-Revilla J, Anza-Ramirez C, Rubio J, Gonzales GF. Effects of different varieties of Maca (Lepidium meyenii) on bone structure in ovariectomized rats. Forsch Komplementmed. 2010;17(3):137-43. Epub 2010 Jun 16.
5 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 Jun 23;6:23.
6 Clément C, Diaz Grados DA, Avula B, Khan IA, Mayer AC, Ponce Aguirre DD, Manrique I, Kreuzer M. Influence of colour type and previous cultivation on secondary metabolites in hypocotyls and leaves of maca (Lepidium meyenii Walpers). J Sci Food Agric. 2010 Apr 15;90(5):861-9.
7 Meissner H.O., Mrozikiewicz P.M., Bobkiewicz-Kozlowska T. et al. Hormone-balancing effect of pre-gelatinised organic Maca (Lepidium peruvianum Chacon): (I) Biochemical and pharmacodynamic study on Maca using clinical laboratory model on ovariectomised rats. I. J. B. S., 2006; 2: 260
8 Meissner H.O., Kapczynski W., Mscisz A. et al. Use of Gelatinised Maca (Lepidium peruvianum) in Early–Postmenopausal Women – a Pilot Study. I. J. B. S., 2005; 1: 33
9 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 Nov-Dec;15(6):1157-62.
10 Oshima M, Gu Y, Tsukada S. Effects of Lepidium meyenii Walp and Jatropha macrantha on blood levels of estradiol-17 beta, progesterone, testosterone and the rate of embryo implantation in mice. J Vet Med Sci. 2003 Oct;65(10):1145-6.
11 Mazaro-Costa R, Andersen ML, Hachul H, Tufik S. Medicinal plants as alternative treatments for female sexual dysfunction: utopian vision or possible treatment in climacteric women? J Sex Med. 2010 Nov;7(11):3695-714. doi: 10.1111/j.1743-6109.2010.01987.x. Epub 2010 Aug 16.
12 Carter R. Clinical Effects of a Proprietary, Standardized, Concentrated, Organic Lepidium Peruvianum Formulation (Maca-GO®) as an Alternative to HRT 2007
13 Meissner HO, et al. Use of Gelatinized Maca (Lepidium peruvianum) in Early Postmenopausal Women—a Pilot Study. IJBS 2005, 1(1):33-45
14 Meissner HO, et al. Hormone-Balancing Effect of Pre-Gelatinized Organic Maca (Lepidium peruvianum Chacon): (II) Physiological and Symptomatic Responses of Earlypostmenopausal Women to Standardized Doses of Maca in Double Blind, Randomized, Placebo-Controlled, Multi-Centre Clinical Study. IJBS 2006, 2(4):360-374
15 Gonzales GF, Cordova A, Gonzales C, et al. Lepidium meyenii (Maca) improved semen parameters in adult men. Asian J Androl 2001, 3(4):301
16 Obregon LV. “Maca” Planta Medicinal y Nutritiva del Peru. 1 Edition Lima: Instituto de Fitoterapia Americano. 2001, 1-182
17 Chacon de Popovici, Gloria. Maca (Lepidium peruvianum Chacon), Millenarian Peruvian Food Plant, With Highly Nutritional and Medicinal Properties. 1st Edition. Universidad Nacional Mayor de San Marcos. Lima, Peru. 2001, 1-337
18 Chacon G. Pytochemical study on Lepidium meyenii. PhD Thesis. Universidad Nacional Mayor de San Marcos. Lima, Peru. 1961, 1-46
19 Meissner H.O., Kedzia B., Mrozikiewicz P.M., et al. Short- and Long- Term Physiological responses of Male and Female Rats to Two Dietary Levels of Pre-Gelatinised Maca (Lepidium peruvianum Chacon). I.J.B.S., 2006; 2: 15
20 Zhao J, Avula B, Chan M, Clément C, Kreuzer M, Khan IA. Metabolomic Differentiation of Maca (Lepidium meyenii) Accessions Cultivated under Different Conditions Using NMR and Chemometric Analysis. Planta Med. 2011 Aug 19. [Epub ahead of print]