Human and Animal Studies
Unspecified Colors
Despite the compelling evidence that the colors of maca vary in their composition and impact on various health conditions, much of the published literature does not disclose the color(s) studied, creating a challenge in understanding the potential health benefits and highlighting the need for color-specific studies to be completed. A 2022 systematic review and meta-analysis revealed that 50% of the articles published did not state the color(s) used.
The research suggests that maca, without specifying the color(s), support:
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Mood regulation (anxiety and depression)
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Sexual health (libido, erectile dysfunction
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Reproductive health (sperm health
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Cardiometabolic health (blood pressure, cholesterol, triglycerides, glucose)
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Lowering inflammation
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Energy
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Menopausal symptoms (hot flashes, insomnia)
Below is a compilation of the available human and animal studies for unspecified colors of maca with a comprehensive overview of the study details provided. Use the Filter button to narrow your search.
At this time, published articles are not available to fit your search criteria.
Effect of a lipidic extract from lepidium meyenii on sexual behavior in mice and rats
PMID: 10736519
About the Study
Type of study: Animal study, 22 days
Population: 8-10 weeks old, male and female mice and rats, strain Shenyang, grade II, N=45 male, N=90 virgin female
Aim of the study: To determine the effect of oral administration of a purified lipidic extract from Lepidium meyenii (MacaPure M-01 and M-02) on the number of complete intromissions and mating in normal mice, and on the latent period of erection (LPE) in rats with erectile dysfunction.
Maca Details
Species: Lepidium meyenii, MacaPure M-01 and M-02
Source of maca: Not stated
Location where maca was grown: Peru
Agricultural methods used: Not stated
Part of maca used: Dried root
Form of maca: Purified powder extract
Dose: Varying doses for 22 days, oral administration
Outcomes
Results:
The number of complete intromissions increased significantly with M-01 and M-02 treated groups (p<0.01) with the dose of 40 mg/g body weight
Day 1 of mating, M-01, dose 4 g/kg body weight increased the number of sperm-positive female (p<0.01).
"The present study reveals for the first time an aphrodisiac activity of L. meyenii, an Andean Mountain herb."
Other details:
M-01 contained more polysaccharides and less macaenes and macamides compared to M-02.
Lepidium meyenii (Maca) enhances the serum levels of luteinising hormone in female rats
About the Study
Type of study: Animal study, 7 weeks
Population: Female Sprague-Dawley rats
Aim of the study: To investigatd the effect of maca on the serum pituitary hormone levels during the pro-oestrus phase.
Maca Details
Species: Lepidium meyenii
Source of maca: Yamano del Perú SAC
Location where maca was grown: Junín Plateau (Peru)
Agricultural methods used: Not stated
Part of maca used: Tuber
Form of maca: Powder
Dose: Diet containing 5%, 25% or 50% maca powder
Outcomes
Results:
A significant increase in luteinizing hormone (4.5-fold increase, p<0.01) and follicle stimulating hormone levels (19-fold increase, p<0.01) in the group fed 50% maca powder.
A dose dependent increase of luteinizing hormone was observed within the range of 3-30g/kg body weight.
"The present study demonstrates that Maca uniquely enhances the LH serum levels of pituitary hormones in female rats during the pro-oestrus LH surge and acts in a pharmacological, dose-dependent manner. These findings support the traditional use of Maca to enhance fertility and suggest a potential molecular mechanism responsible for its effects."
Phytochemical Evaluation of Lepidium meyenii, Trigonella foenum-graecum, Spirulina platensis, and Tribulus arabica, and Their Potential Effect on Monosodium Glutamate Induced Male Reproductive Dysfunction in Adult Wistar Rats
PMID: 39199185
About the Study
Type of study: Animal study, 35 days
Population: Healthy male Wistar rats, N=36
Aim of the study: To assess the phytochemical properties of Lepidium meyenii, Trigonella foenum-graecum, Spirulina platensis, and Tribulus arabica and their potential impact on MSG-induced impairment of reproductive parameters.
Maca Details
Species: Lepidium meyenii
Source of maca: Dubai, UAE (public market)
Location where maca was grown: Not stated
Agricultural methods used: Not stated
Part of maca used: Not stated
Form of maca: Aqueous extract
Dose: 500 mg/kg/day
Outcomes
Results:
Four (4) botanicals were researched (Lepidium meyenii (maca), Trigonella foenum-graecum (fenugreek), Spirulina platensis (spirulina), and Tribulus arabica (Tribulus)).
The phytochemical property results of maca extract are as follows:
Percentage of phenolic contents: 0.673% (3rd highest of the botanicals); six active compounds-predominantly syringic acid and ellagic acid.
Percentage of flavonoid contents: 0.010% (lowest of the botanicals); six active compounds-predominantly naringin
Maca exhibited the highest antioxidant activity
The impact on reproductive parameter results of maca extract are as follows:
Total sperm motility was restored (p<0.05), ameliorating the adverse effects of MSG
Testosterone levels improved (in all groups without statistical differences)
Highest number of ells in seminiferous tubules
“This current study revealed that Lepidium meyenii, Trigonella foenum-graecum, and Tribulus arabica, respectively, have potential benefits for male fertility with the most significant results seen with Lepidium meyenii.”
Other details:
A significant increase in the prostate gland was observed with Tribulus and spirulina.
Effect of ethanol extract of Lepidium meyenii Walp. on osteoporosis in ovariectomized rat
About the Study
Type of study: Animal study, 28 weeks
Population: Female Sprague-Dawley, ovariectomized rats
Aim of the study: To evaluate the effect of ethanol extract of maca on postmenopausal osteoporosis in ovariectomized rats.
Maca Details
Species: Lepidium meyenii
Source of maca: Not stated (Abstract only)
Location where maca was grown: Not stated (Abstract only)
Agricultural methods used: Not stated (Abstract only)
Part of maca used: Not stated (Abstract only)
Form of maca: Ethanol extract
Dose: 0.096 or 0.24 g/kg body weight
Outcomes
Results:
"The findings derived from the basis of bone mineral density, biomechanical, biochemical and histopathological parameters indicated that higher dose of ethanol extract of Maca was effective in the prevention of estrogen deficient bone loss."
Preservation of Cognitive Function by Lepidium meyenii (Maca) Is Associated with Improvement of Mitochondrial Activity and Upregulation of Autophagy-Related Proteins in Middle-Aged Mouse Cortex
About the Study
Type of study: Animal study, 5 weeks
Population: 14-month-old (middle-aged) male ICR mice, N=14
Aim of the study: To investigate if maca could improve cognitive function of middle-aged mice and if this effect was associated with improvement of mitochondrial activity and modulation of autophagy signaling in mouse cortex.
Maca Details
Species: Lepidium meyenii
Source of maca: Nanjing Bio-Array Technology Company
Location where maca was grown: Peru
Agricultural methods used: Not stated
Part of maca used: Not stated
Form of maca: Powder
Dose: 0.1mL/10 g body weight or 500 mg/kg body weight
Outcomes
Results:
Maca treated mice had improvements in memory retention.
Improved motor coordination was observed in mice that were administered maca.
A significant increase in swim time to exhaustion, suggesting maca's antifatigue property.
A significant increase in oxidative phosphorylation enzyme complexes, suggesting an improvement in mitochondrial function.
A significant upregulation of the expression of autophagy-related proteins.
"In summary, the present study demonstrated for the first time that maca improves cognitive function in middle-aged mice, and this effect may be associated with improved mitochondrial respiratory function and upregulation of autophagy-related proteins."
Lepidium meyenii Walp Exhibits Anti-Inflammatory Activity against ConA-Induced Acute Hepatitis
About the Study
Type of study: Animal study
Population: 8-10 weeks old female BALB/c mice, N=40
Aim of the study: To determine the therapeutic effects of maca on liver inflammation and injury for the first time, and we investigated the cellular and molecular changes in CIH treated by the administration of maca extract.
Maca Details
Species: Lepidium meyenii
Source of maca: Yunnan Institute of Materia Medica, China
Location where maca was grown: China
Agricultural methods used: Not stated
Part of maca used: Not stated
Form of maca: Freeze-dried extract
Dose: 10mg/mL
Outcomes
Results:
Maca extract
Significantly suppressed multiple inflammatory cytokines
Moderated liver injury in ConA-induced acute hepatitis
Suppressed infiltration of natural killer T cells and macrophages
"In this study, we found that the protective effects of Maca extract ameliorate ConA-induced acute hepatitis (CIH) and underlying mechanisms."
Abbreviations: Con-A: Concanavalin A; CIH: ConA-induced acute hepatitis
Effect of ethanolic extract of Lepidium meyenii Walp on serum hormone levels in ovariectomized rats
About the Study
Type of study: Animal study, 28 weeks
Population: Female Sprague-Dawley, ovariectomized or sham rats, N=50
Aim of the study: To evaluate the effect of long-term ethanol extract of Lepidium meyenii (Maca) on serum hormone levels in ovariectomized (OVX) rats and compare them with the effect of diethylstilbestrol.
Maca Details
Species: Lepidium meyenii
Source of maca: Chinese Maya Bioengineer Co, Hubei, imported from Peru
Location where maca was grown: Lima, Peru
Agricultural methods used: Not stated
Part of maca used: Root
Form of maca: Ethanolic extract
Dose: 0.096 (low dose) or 0.24 (high dose) g/kg body weight
Outcomes
Results:
At 12 weeks, no significant changes were observed in estradiol or FSH using the low dose, though a significant decrease in testosterone was noted (p<0.05).
At 28 weeks, a significant increase in estradiol (p<0.05) occurred with the low dose and a significant decrease in FSH (p<0.01) was observed using both doses of maca.
The higher dose of maca did not affect estradiol levels.
Lepidium meyenii (Maca) reversed the lead acetate induced -- damage on reproductive function in male rats
About the Study
Type of study: Animal study, 35 days
Population: 3-month-old male rats, Holtzman strain, N=49
Aim of the study: To determine whether the treatment with maca may be useful for the treatment of the deleterious effect of lead acetate (LA) administration on spermatogenesis in rats.
Maca Details
Species: Lepidium meyenii
Source of maca: Not stated
Location where maca was grown: Carhuamayo, Junín, Peru
Agricultural methods used: Traditional methods
Part of maca used: Dried hypocotyls
Form of maca: Aqueous extract
Dose: 2.2g/kg, oral administration
Outcomes
Results:
Maca protected spermatogenesis and increased epididymal sperm count.
Maca administration reduced the deleterious effect on daily sperm production caused by lead acetate (LA) treatment.
Maca prevented LA-induced spermatogenic disruption in rats and it may become in a potential treatment of male infertility associated with lead exposure.
Other details:
Rats were treated with 0, 8, 16, and 24 mg/kg of lead acetate. Maca was co-administered days 18-35. N=7 per group
Abbreviations: LA: lead acetate
The improvements of daily fatigue in women following the intake of maca (Lepidium meyenii) extract containing benzyl glucosinolate.
About the Study
Type of study: Human study, 4-week randomized, double-blind, placebo-controlled, parallel-group comparison study
Population: N=60, healthy Japanese women 20-65 years old, with daily fatigue. [3 participants withdrew from the study, 2 were excluded.]
Aim of the study: To assess the effects of maca on reducing fatigue
Maca Details
Species: Lepidium meyenii
Source of maca: Provided by Kinos Inc. Tokyo, Japan
Location where maca was grown: Not stated
Agricultural methods used: Not stated
Part of maca used: Not stated
Form of maca: Concentrated extract containing 9.6 mg/day of benzyl glucosinolate
Dose: 200 mg capsule, twice daily, undesignated time
Outcomes
Results:
Significant decrease in fatigue (p<0.001), as measured by visual analogue scale (VAS) in women 20-45 years old
Other details:
Authors state that maca polysaccharides may provide anti-fatigue effect and benzyl glucosinolates may provide anti-fatigue effects due to its antioxidant capacity.
No adverse effects were reported/observed.
Does Lepidium meyenii (Maca) improve seminal quality?
About the Study
Type of study: Human study, 12-week, prospective, randomized, double-blind, placebo-controlled parallel trial
Population: N=69, 20–40-year-old males diagnosed with mild asthenozoospermia and/or mild oligozoospermia; two participants were lost to follow-up
Aim of the study: To assess the effect of maca on seminogram parameters.
Maca Details
Species: Lepidium meyenii
Source of maca: Not stated
Location where maca was grown: Not stated
Agricultural methods used: Not stated
Part of maca used: Not stated
Form of maca: Gelatinized maca, powder
Dose: 2 grams per day (1,000 mg capsule twice daily), capsules
Outcomes
Results:
Significant increase in sperm concentration (p<0.011) by 31.69%
Though not of statistical significance, sperm motility increased by 10.48% and morphology of spermatozoa increased by 6.33%
Other details:
No adverse effects were reported/observed.
N=9 were smokers, it is noted that this lifestyle factors can impact seminal variables.
Clinical effect of oral administration of maca (Lepidium meyenii) extract on Japanese peri-menopausal women subjects: A randomized, double-blind, placebo-controlled study.
About the Study
Type of study: Human study, 8-week, randomized, double-blind, placebo controlled, parallel clinical study
Population: N=42, healthy peri-menopausal Japanese women, 40-59 years old [1 patient did not complete the study]
Aim of the study: Effect of maca extract containing at least 1.2% of benzylglucosinolate (Maca-BG1.2™) on the serum level of hormones and menopausal disorder of Japanese peri-menopausal women
Maca Details
Species: Lepidium meyenii
Source of maca: Maca-BG1.2™ was purchased from CPX PERU S.A.C (Lima, Peru)
Location where maca was grown: Peru
Agricultural methods used: Washed, sliced and oven dried, hydrous ethanol and evaporation to prepare powdered named Maca-BG1.2™ containing at least 1.2% benzylglucosinolate.
Part of maca used: Not stated
Form of maca: Extract
Dose: 300 mg/day, (two 150 mg capsules daily) after morning meal
Outcomes
Results:
E2 levels showed a 2.2-fold increase though not of significance; further analysis revealed serum E2 level in the peri-menopausal subjects with regular menstruation cycle displayed a mostly significant change
Marginal decrease in insomnia and hot flushes. Women with mild symptoms achieved the greatest improvements in reducing menopausal symptoms.
Other details:
No serious effects were observed
GABA content of maca may have contributed to improvements in insomnia
Maca reduces blood pressure and depression, in a pilot study in postmenopausal women
About the Study
Type of study: Human study, 12-week, randomized, single-center, double-blind, placebo-controlled, cross-over study (6 weeks maca and 6 weeks placebo)
Population: N=34, post-menopausal Chinese women (From Hong Kong); 46-59 years old; N=29 completed the trial
Aim of the study: To assess the effect of maca for menopausal symptoms and health-related quality of life; to assess effect of maca on hormones
Maca Details
Species: Lepidium meyenii
Source of maca: Maca Power, Healthychoices, Murwillumbah, NSW, Australia
Location where maca was grown: Peru
Agricultural methods used: Not stated
Part of maca used: Not stated
Form of maca: Not stated
Dose: 3.3 grams per day, 7 capsules per day, 4 capsules following breakfast, 3 capsules following dinner
Outcomes
Results:
After 6 weeks of treatment, the maca group showed significant changes in:
Decrease in systolic (p=0.05) and diastolic (p=0.01) blood pressure
10.8% increase general well-being (p<0.05)
13.5% increase mental health (p<0.05)
16.4% increase social functioning (p<0.05)
13% increase mental component score (p<0.05)
Significant reduction of menopausal symptoms measured by GCS by 30% (p=0.04) including reduction in anxiety (p=0.02, depression (p<0.01) and somatic (p<0.03)
No differences in E2, FSH, LH, SHBG, glucose, lipid profile, serum cytokines or vasomotor symptoms
Other details:
Flavonoids in maca may contribute to the favorable outcomes on reduction depression and anxiety
No adverse effects were reported/observed
Authors note that women in non-Western countries do not typically report on sexual function, mental states, or symptoms commonly associated to menopause. (i.e., only 5-10% of Asian women report concerns of vasomotor symptoms compared to nearly 80% of Western women.)
A placebo-controlled double-blind randomized trial of the effect of oral supplementation with spermotrend, maca extract (Lepidium meyenii) or l-carnitine in semen parameters of infertile men
About the Study
Type of study: Human study, 90-days, prospective, randomized, double-blind placebo-controlled study
Population: N=60 infertile, healthy men
Aim of the study:To evaluate the effect of placebo to three supplements in improving seminal parameters on infertile patients. Supplements included maca, L-carnitine and Spermotrend
Maca Details
Species: Lepidium meyenii
Source of maca: Provided by Nature Way Product, Inc.
Location where maca was grown: Not stated [abstract only]
Agricultural methods used: Not stated [abstract only]
Part of maca used: Not stated [abstract only]
Form of maca: Not stated [abstract only]
Dose: 1 gram twice daily
Outcomes
Results:
Maca improved sperm motility (p<0.05)
Other Details:
Abtract only
Role of maca (Lepidium meyenii) consumption on serum interleukin-6 levels and health status in populations living in the Peruvian Central Andes over 4000 m of altitude
About the Study
Type of study: Cross-sectional, population-based study, comparing individuals who consumed maca, as a food source, to those who did not.
Population: N=50, men and women, 35-69 years old, living in Junín, Peru (4,100 meters above sea level) N=27 were regular maca consumers.
Aim of the study: Hypothesis: Consumption of maca at high altitudes may be associated with lower serum IL-6 values and therefore higher markers of health status. Measurements included: health related quality of life (HRQL) questionnaires, lower limb strength, hemoglobin levels, blood pressure, hormone levels (testosterone and estradiol), IL-6, chronic mountain sickness (CMS) score.
Maca Details
Species: Lepidium meyenii
Source of maca: N/A-population based study in which participants were consuming maca as a food source
Location where maca was grown: Peru
Agricultural methods used: Not stated
Part of maca used: Not stated
Form of maca: 96% consumed maca as a juice, prepared at home
Dose: Average time consuming maca was 25.8+/- 3.2 years
Outcomes
Compared to non-consumers, the regular consumers of maca had:
Higher serum Estradiol (E2) (p<0.01) and health scores (p<0.01)
Lower
systolic blood pressure (p<0.05)
serum testosterone (T) levels (p<0.05)
T/E2 ratio (p<0.05)
serum IL-6 levels (p<0.05) [The lowest IL-6 levels were observed when maca was consumed in greater quantities (15.9+/- 3.08 grams per day) and for the longer durations (17.8 +/-4.48 years for 41.9+/- 4.48 days per year)]
CMS scores (p<0.01)
Performed better on the lower limb strength test (p<0.01)
First case report of testosterone assay-interference in a female taking maca (Lepidium meyenii)
About the Study
Type of study: Human Case Report
Population: N=1, Caucasian female in her 30s
Aim of the study: To report on the negative experience of one woman using maca extract
Maca Details
Species: Lepidium meyenii
Source of maca: Not stated
Location where maca was grown: Not stated
Agricultural methods used: Not stated
Part of maca used: Not stated
Form of maca: Extract
Dose: 1 tsp. of maca powder added to milk one time daily
Outcomes
Results:
Maca consumption increased plasma testosterone levels without features of virilization.
Testosterone immunoassays use direct immunoassays which are prone to interference from androgenic compounds resulting in falsely elevated testosterone levels. Maca may cause testosterone immunoassay interference in females.
Other details:
Patient was taking maca to help with energy and libido (This was not reported on.)
Effect of the Lepidium meyenii (Maca) on the spermatogenesis and the spermatic quality of subjects with diagnosis of infertility: study of cases
About the Study
Type of study: Human study, 12 weeks, other details not stated [Abstract only]
Population: N=10 infertile males, 25-50 yo
Aim of the study: Effect of maca on spermatogenesis and spermatic quality in subjects diagnosed with infertility.
Maca Details
Species: Lepidium meyenii
Source of maca: Not stated
Location where maca was grown: Not stated [Abstract only]
Agricultural methods used: Not stated [Abstract only]
Part of maca used: Not stated [Abstract only]
Form of maca: Not stated [Abstract only]
Dose: 3,000 mg/day
Outcomes
Results:
Improvements in sperm motility (p<0.0001), vitality (p<0.01) and morphology (p<0.01), immature germ cell (p<0.01)
No changes in hormone levels
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
About the Study
Type of study: Human study, 12-weeks, double-blind, randomized clinical trial
Population: N=50, Caucasian men with mild ED 36 years old +/- 5 years
Aim of the study: To assess the effect of maca on non-Peruvian men for the efficacy on subjective well-being and erectile dysfunction (ED).
Maca Details
Species: Lepidium meyenii
Source of maca: Provided by Ibersan Srl, Forli, Italy
Location where maca was grown: Peru
Agricultural methods used: Not stated
Part of maca used: Root
Form of maca: Pulverized, dehydrated tablets
Dose: 2.4 grams per day (1,200 mg bid) as tablets
Outcomes
Results:
While both the placebo group and maca group reported significant improvements, the maca group experienced:
More significant effects after 12 weeks of treatment per the International Index of Erectile Function (IIEF-5) score (p< 0.001)
Improvement in psychological performance-related Satisfaction Profile (SAT-P) score, (p< 0.05)
Only maca-treated patients experienced a significant improvement in physical and social performance-related SAT-P score compared with the baseline (p< 0.05)
Other details:
No adverse effects were reported/observed
A pilot investigation into the effect of maca supplementation on physical activity and sexual desire in sportsmen
About the Study
Type of study: Human study, 14 days, randomized, double-blind, cross-over design (1 week washout period)
Population: N=8, experienced endurance trained male cyclists, 30 +/- 7 years
Aim of the study: Effect of maca extract supplementation on endurance performance and sexual desire in trained male cyclists after 14 days of use.
Maca Details
Species: Lepidium meyenii
Source of maca: Maca root voucher no. F15/32/A7, reference no. PW0889
Location where maca was grown: Cerro de Pasco region of Peru
Agricultural methods used: Not stated
Part of maca used: Root
Form of maca: Gelatinized extract
Dose: 2,000 mg per day (5 capsules containing 400 mg each)
Outcomes
Results:
Significantly improved 40 km cycling time performance compared to the baseline test (P=0.01), but not compared to the placebo trial after supplementation (P>0.05)
Significantly improved the self-rated sexual desire score compared to the baseline test (P=0.01), and compared to the placebo trial after supplementation (P=0.03)
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
About the Study
Type of study: Human study, 12-week, randomized, double-blind, placebo-controlled, crossover trial (6 weeks of maca and 6 weeks of placebo)
Population: N=16, post-menopausal women, 50-60 years old, 2 did not complete the trial
Aim of the study: To examine the estrogenic and androgenic activity of maca and its effect on the hormonal profile and symptoms in postmenopausal women.
Maca Details
Species: Lepidium meyenii
Source of maca: Maca Power, Incan Food, Murwillumbah, NSW, Australia
Location where maca was grown: Peru
Agricultural methods used: Not stated
Part of maca used: Not stated
Form of maca: Dried maca powder
Dose: 3.5 grams one time per day, powder taken in breakfast cereal, soup, or a milk shake
Outcomes
Results:
No estrogenic or androgenic activity was detected in the maca used for the study.
Significant reduction (p<0.05, 30%) in symptoms as rated by GCS, including decreased anxiety and depression and improved sexual function (p<0.05)
No differences were seen in serum concentrations of estradiol, follicle-stimulating hormone, luteinizing hormone, and sex hormone-binding globulin
Post hoc analyses revealed significant increase in estradiol would only be detected at a 30% increase.
Other details:
Positive effects are independent of estrogenic or androgenic activity
Proposed action of maca is related to the phytoestrogenic activity of A-sitosterol flavonoids present in maca are potent inhibitors of monoamine oxidase activity
A double-blind, randomized, pilot dose-finding study of maca root (L. meyenii) for the management of SSRI-induced sexual dysfunction
About the Study
Type of study: Human study, 12-week, double-blind, randomized, parallel group dose-finding pilot study
Population: N=20, 17-women, 3=men, with major depressive disorder (MDD) on anti-depressant medication(s) for a minimum of 8 weeks
Aim of the study: Assess effectiveness of maca for sexual dysfunction induced by SSRI treatment and to determine if a low or high dose altered outcomes.
Maca Details
Species: Lepidium meyenii
Source of maca: Purchased from A Healthy Alternative (ahealthya.com) in Long Island, NY.
Location where maca was grown: Not stated
Agricultural methods used: Not stated
Part of maca used: Root
Form of maca: Not stated
Dose: 1.5 g/day (low dose) or 3.0 g/day (high dose), capsules
Outcomes
Results:
Both dosing groups had significant improvement in mean ASEX and MGH-SFQ score.
For the group taking 3 g/ day:
An increased improvement in sexual function was observed compared to the low dose group, as measured by ASEX (p=0.028) and MGH-SFQ (p=0.017)
Significant improvement in libido (P<0.05), with increased sexual attempts (p=0.048) and enjoyment (p=0.019)
Small but significant decrease in depressive symptoms (p=0.047)
Other details:
Adverse events reported as GI upset (n = 5), headache (n = 2), irritability (n = 2), panic attack (n = 1), urinary frequency (n = 1), blurry vision (n = 1), sleep disruption (n = 1), increased sweating (n = 1), increased dreaming (n = 1), thicker menstrual discharge (n = 1), and fibromyalgia exacerbation (n = 1). These events were reported as transient and did not lead to discontinuation of the supplement.
Abbreviations: ASEX:Arizona Sexual Experience Scale; MGH-SFQ:Massachusetts General Hospital Sexual Function Questionnaire
Effect of Lepidium meyenii (Maca), a root with aphrodisiac and fertility-enhancing properties, on serum reproductive hormone levels in adult healthy men
About the Study
Type of study: Human study, 12-week double-blind, placebo-controlled, randomized, parallel trial
Population: N=56, men 21-56 years old
Aim of the study:To test the hypothesis that maca has no effect on serum reproductive hormone levels in apparently healthy men when administered in doses used for aphrodisiac and/or fertility-enhancing properties
Maca Details
Species: Lepidium meyenii
Source of maca: Maca Gelatinizada from Laboratorios Hersil
Location where maca was grown: La Molina-Lima, Peru
Agricultural methods used: Not stated
Part of maca used: Root
Form of maca: Dehydrated, gelatinized root
Dose: 3 groups: 1) 500 mg tid, every eight hours 2) 1,000mg tid, every eight hours3) 1,500 mg qd in the morning
Abbreviations: tid: three times daily; qd: one time daily
Outcomes
Results:
Results of the three groups did not differ.
Sexual desired increased in all three groups at weeks 8 and 12.
At week 2, a significant increase in 17-alpha hydroxyprogesterone was observed in the group treated with 3,000 mg, but after assessing as a percentage, there was no significant difference.
No other hormones (testosterone, prolactin, FSH, LH, or estradiol) were significantly increased or decreased.
Abbreviations: FSH: follicle stimulating hormone; LH: luteinizing hormone
Effect of Lepidium meyenii (MACA) on sexual desire and its absent relationship with serum testosterone levels in adult healthy men.
About the Study
Type of study: Human study, 12-week, double-blind placebo-controlled, randomized, parallel trial
Population: N=57, healthy men 21-56 years old
Aim of the study: To demonstrate if the effect of maca on sexual desire was because of effect on mood or serum testosterone levels.
Maca Details
Species: Lepidium meyenii
Source of maca: Maca Gelatinizada from Laboratorios Hersil
Location where maca was grown: La Molina-Lima, Peru
Agricultural methods used: Not stated
Part of maca used: Root
Form of maca: Gelatinized, dehydrated root
Dose: 1,500 mg (three 500 mg capsules per day) or 3,000 mg (six 500 mg capsules per day)
Outcomes
Results:
At week 8, the group treated with maca had a significant increase (40%) in sexual desire (p<0.008)
At week 12, the group treated with maca had a significant increase (42.2%) in sexual desire (p<0.006)
No differences in the effect were noted between the dosing groups.
No changes in hormone levels (testosterone or estradiol) or mood (depression/anxiety) were observed.
Other details:
Authors note the effect of maca on sexual desire could be because of any unknown chemical signal, i.e., phytoestrogens
Lepidium meyenii (Maca) improved semen parameters in adult men
About the Study
Type of study: Human study, 4-month intervention trial
Population: N=9, males, 24-44 years old
Aim of the study: To determine effect of maca on seminal analysis
Maca Details
Species: Lepidium meyenii
Source of maca: Maca Gelatinizada La Molina tablets provided by the Laboratorios Hersil (Lima, Peru), which could also be purchased in the pharmacy.
Location where maca was grown: Peru
Agricultural methods used: Unknown (Abstract only)
Part of maca used: Root
Form of maca: Unknown (Abstract only)
Dose: 1,500 or 3,000 mg/day tablets
Outcomes
Results:
Treatment with maca resulted in increased seminal volume (p<0.05), total sperm count (p<0.05), motile sperm count (p<0.05), semen volume ((p<0.05) and sperm motility (p<0.05).
Increase of sperm count was not related to dose of maca.
Serum hormone levels were not modified with maca treatment.
Other details:
Authors state improvements in sperm production and motility were not related to mechanisms of luteinizing hormone, follicle stimulating hormone, prolactin, testosterone, or estradiol.