A small randomized, double-blind, placebo-controlled, crossover trial of fourteen postmenopausal women was completed using 3.5 gm of powdered Maca (Lepidium meyenii) for 6 weeks and matching placebo for 6 weeks. Measurements of estradiol, follicle-stimulating hormone (FSH), luteinizing hormone (LH), and sex hormone binding globulin (SHBG) were taken at baseline, and weeks 6 and 12. The Greene Climacteric Scale was used to assess the severity of menopause symptoms. Serum concentrations of estradiol, FSH, LH and SHBG were similar in both groups. The Greene Climacteric Scale revealed a significant reduction in psychological symptoms including anxiety, depression and sexual dysfunction after Maca consumption compared with baseline and -placebo. These findings were independent of androgenic or alpha-estrogenic activity present in the Maca using assays to measure hormone-dependent activity.
This study on a Maca preparation adds to the growing body of evidence utilizing Maca for menopause related symptoms. Having significant effects on anxiety and depression is terrific, but many women – in this study appear to be independent of any measurable influence on sex hormones or SHBG and presumably therefore independent of any action related to the activity of beta-sitosterol, found in Maca. These findings are not consistent with Meissner et al. (Meissner H et al. Use of gelatinized Maca [Lepidium peruvianum] in early postmenopausal women- a pilot study. Int J Biomed Sci 2005;1:33-45) who reported an elevation in LH and estradiol and a decrease in FSH. These variable results may be due to differences in dosing, type of commercial preparation used in each study, species or variety of Lepidium from which the preparations are made, extraction protocols and delivery techniques. The effect on depression and anxiety are consistent in several studies and it is thought that the flavonoids in Maca inhibit monoamine oxidase activity. The improvement in sexual function in postmenopausal women observed in this study is consistent with research using Maca in men and also in rodents.
- Brooks N, Wilcox G, Walker K, et al. 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(6):1157-1162.