Human Studies
Red Maca
The overview of research suggests that red maca supports:
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prostate health
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bone health
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skin health
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detoxification support
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brain health
The evidence is limited for the use of red maca on these health conditions with the exception of prostate health, which has been extensively studied in animals.
Below is a comprehensive overview of the animal and human studies available for red maca.
Red Maca (Lepidium meyenii), a Plant from the Peruvian Highlands, Promotes Skin Wound Healing at Sea Level and at High Altitude in Adult Male Mice
About the Study
Type of study: Animal study
Population: Male mice, Balb/c strains
Aim of the study: To determine the effect of high altitude on tissue repair and the effect of the topical administration of the spray-dried extract of red maca (RM) in tissue repair.
Maca Details
Species: Lepidium meyenii
Source of maca: Locally purchased in Lima, Peru
Location where maca was grown: Carhuamayo, ( Junin, Peru)
Agricultural methods used: Not stated
Part of maca used: Hypocotyls
Form of maca: Spray dried powder
Dose: 1.6μg red maca/200mg cream, 16μg red maca/200mg cream, or 160μg red maca/200mg cream, topical application
Outcomes
Results:
Delayed wound healing and increased inflammatory cell activity was observed in the high altitudes.
Red maca accelerated wound closure (p<0.05), decreased epidermal hyperplasia, and decreased the number of neutrophils and increased the number of macrophages at the wound site.
Antagonistic effect of Lepidium meyenii (red maca) on prostatic hyperplasia in adult mice
About the Study
Type of study: Animal study, 7, 14, and 21 days
Population: 10-week-old, adult male mice
Aim of the study: To determine the effect of red maca (RM) in the prostate hyperplasia induced with testosterone enanthate (TE) in adult mice.
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: Hypocotyl
Form of maca: Hydroalcoholic extract
Dose: 140 mg/kg BW, oral administration, for 7, 14, or 21 days
Outcomes
Results:
Red maca reduced prostate weight in 21 days, prostate acini in 14 days, and stromal area in 7 days (p<0.05).
Polyphenol content of red maca increased in the aqueous fraction compared to pulverized maca.
Other details:
Prostate hyperplasia was induced with testosterone enanthate (TE). Hydroalcoholic extract of red maca was then compared to Finasteride, as the control.
Effect of two different extracts of red maca in male rats with testosterone-induced prostatic hyperplasia
About the Study
Type of study: Animal study, 14 days
Population: 3-month-old, adult male rats, Holtzman strain, N=36
Aim of the study: To determine the effect of two different extracts of red maca in male rats.
Maca Details
Species: Lepidium meyenii
Source of maca: Not stated
Location where maca was grown: Carhuamayo, Junin, Peru
Agricultural methods used: Not stated
Part of maca used: Hypocotyls
Form of maca: Freeze-dried aqueous extract and spray dried hydroalcoholic extract
Dose:
Outcomes
Results:
Spray dried hydroalcoholic extract had higher content of benzyl glucosinolates compared to freeze-dried red maca.
A significant reduction in prostate weight occurred from freeze-dried aqueous extract (p<0.01), hydroalcoholic extract (p<0.05), and finasteride (p<0.01) administration.
Both extracts of maca did not have an impact on seminal vesicle weight.
A dose dependent reduction in prostate weight was observed with higher doses of benzyl glucosinolates in the red maca extracts.
Other details:
Prostatic hyperplasia was induced in male rats with testosterone enanthate (TE) and two extracts of red maca were compared.
Inflammatory pathway employed by Red Maca to treat induced benign prostatic hyperplasia in rats
PMID: 31989657
About the Study
Type of study: Animal study, 12 weeks
Population: Adult male rats, Holtzman strain, N=30
Aim of the study: To assess the inflammatory effect of red maca and finasteride in rats with testosterone enanthate (TE)-induced benign prostatic hyperplasia (BPH).
Maca Details
Species: Lepidium meyenii
Source of maca: Not stated
Location where maca was grown: Junín, Peru
Agricultural methods used: not stated
Part of maca used: Hypocotyls
Form of maca: Spray dried hydroalcoholic extract
Dose: 40 and 80 mg, dissolved in water
Outcomes
Results:
"Red Maca and finasteride treatments decreased inflammatory cells counts in prostate, inhibiting TNF-a by different pathways."
"Finasteride increased IL4 whereas Red Maca increased INF-g."
"In conclusion, data suggest that finasteride acts on Th2 response by increasing IL4 in prostate, while Red Maca acts on Th1 response mediated by INF-g."
Other details:
Doses of 40 mg and 80 mg of red maca were compared against control and finasteride
Effect of red maca (Lepidium meyenii) on prostate zinc levels in rats with testosterone-induced prostatic hyperplasia
PMID: 21762188
About the Study
Type of study: Animal study, 14 days
Population: Male rats, Holtzman strain, N=36
Aim of the study: 1) To determine the effect of red maca on prostate zinc levels in rats with benign prostatic hyperplasia (BPH) induced by testosterone enanthate (TE) 2) To determine the best marker for the effect of red maca on sex accessory glands.
Maca Details
Species: Lepidium meyenii
Source of maca: Not stated
Location where maca was grown: Carhuamayo, Junín, Peru
Agricultural methods used: Not stated
Part of maca used: Hypocotyls
Form of maca: Freeze-dried extract
Dose: 2g raw material/kg BW
Outcomes
Results:
Prostate weight was reduced (p<0.05) starting at day 1 of red maca administration, reversing the effects of BPH induced by TE.
Upon administration, TE increase prostate zinc levels. Red maca (RM) reduced the zinc levels (p<0.05).
"To sum up, RM may regulate prostatic growth by reducing prostate zinc levels in rats where prostatic hyperplasia was induced with TE."
Effect of short-term and long-term treatments with three ecotypes of Lepidium meyenii (MACA) on spermatogenesis in rats
About the Study
Type of study: Animal study, 2 arms-7 and 42 days
Population: 4-month-old male rats, Holtzman strains, N=48
Aim of the study: 1) To determine if treatment with maca for 42 days increases sperm production and epididymal sperm count and motility. 2) To examine the potential activity of red, yellow, and black maca on spermatogenesis.
Maca Details
Species: Lepidium meyenii
Source of maca: Not stated
Location where maca was grown: Carhuamayo, Junín
Agricultural methods used: Not stated
Part of maca used: Hypocotyls
Form of maca: Aqueous extract
Dose: 1.66g/kg BW, oral administration
Outcomes
Results:
In 7 days, the length of stage VIII of the seminiferous tubule were higher (p<0.05) in the maca treated groups compared to the control group.
In 7 days, black maca increased lengths of stages II-VI (p<0.05) and reduced relative length of stages IX-I (p<0.05).
In 7 and 42 days, yellow and black maca increased (p<0.05) epididymal sperm number and spermatids in testis; red maca did not have this effect.
In 7 days, yellow and black maca increased (p<0.05) daily sperm production; red maca did not have an effect.
In 42 days, black maca increased daily sperm production and its efficiency, whereas yellow and red maca did not provide any difference compared to the control group.
In 42 days, increased epididymal sperm motility (p<0.05) was observed with red, yellow, and black maca, but this was not observed at 7 days.
Other details:
Red maca resulted in a decrease of prostate wight after 42 days.
No changes in hormone levels were observed.
The authors conclude that black maca may be a potential treatment for male infertility.
Red maca (Lepidium meyenii) reduced prostate size in rats
About the Study
Type of study: Animal study, 7 days
Population: Adult male rats, Holtzman strain, N=35
Aim of the study: To determine the effect of three ecotypes of maca on ventral prostate of rats.
Maca Details
Species: Lepidium meyenii
Source of maca: Not stated
Location where maca was grown: Carhuamayo, Junin
Agricultural methods used: Natural drying
Part of maca used: Hypocotyls
Form of maca: Aqueous extract of red, yellow, and black extract
Dose: 2g/kg BW daily, oral administration
Outcomes
Results:
Red maca significantly reduced ventral prostate size (p<0.05), while yellow and black maca did not have a significant effect.
Seminal vesicle weight was not impacted by any of the three maca phenotypes.
Yellow maca treated group had higher serum testosterone levels (p<0.05) compared to black maca.
In rats treated with TE and red maca, a reduction in ventral prostate weight was observed at day 14 and was more pronounced at day 42 (p<0.05), with a 50% reduction.
Neither yellow nor black maca were found to have an impact on prostate health.
Antidepressant-Like Behavioral and Spatial Memory Effects in Peruvian Red Maca (Lepidium meyenii)-Treated Rats
About the Study
Type of study: Animal study, 28 days
Population: Male rats, Sprague-Dawley strain and 3-month-old ovariectomized rats, Sprague-Dawley strain
Aim of the study: To study the effects of aqueous extract from Red Maca (AQ-RM) as antidepressant in a depression model in male rats and as enhancer of learning and memory in ovariectomized (OVX) rats.
COLUMN 2
Species: Lepidium meyenii
Source of maca: Not stated
Location where maca was grown: Carhuamayo, Province of Junin
Agricultural methods used: Not stated
Part of maca used: Hypocotyls
Form of maca: Aqueous extracts
Dose: Varied based on experiment group
Maca Details
Species: Lepidium meyenii
Source of maca: Not stated
Location where maca was grown: Carhuamayo, Province of Junin
Agricultural methods used: Not stated
Part of maca used: Hypocotyls
Form of maca: Aqueous extracts
Dose: Varied based on experiment group
Outcomes
Results:
Antidepressant-like behavioral in male rats and spatial memory in ovariectomized (OVX) rats was studied using Fluoxetine and amitriptyline as reference drugs and estradiol for OVX rats.
Red maca has anti-depressive application in male rats (dose of 0.5 and 1.0g/kg body weight)
Red maca (dose 2.0 g/kg body weight) increases the ability of learning and memory in OVX rats in a similar fashion that estradiol does.
Maca extracts and estrogen replacement therapy in ovariectomized rats exposed at high altitude
About the Study
Type of study: Animal study, 28 days
Population: 2-3-month-old, female ovariectomized rats, Sprague-Dawley strain, N=60
Aim of the study: To evaluate whether pre‐treatment with maca (Lepidium meyenii Walp) improved the tolerance to high altitude on an ovariectomized (OVX) rat model at sea level.
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: Aqueous extract of red or black maca
Dose: 1.5 g/kg BW, oral administration
Outcomes
Results:
Red and black maca extracts significantly (P < .001) reduced the malondialdehyde (MDA) (a toxic product from lipid peroxidation) levels in a similar fashion to estradiol (E2).
"Red and black maca extracts had similar effects with E2, by significantly (P < .001) reversing and increasing the ovariectomized induced decrease in cornified endometrial cell number."
Under hypoxic conditions (which generate oxidative stress), the black maca (P < .05) and E2 (P < .01) increased the uterine weight, without recovery of uterine function.
"To the best of our knowledge, this is the first study that shows how black and red maca extracts reduced the lipid peroxidation in a similar way to estradiol..."
Other details:
Animals were treated with estradiol, red maca, or black maca for 28 days, then exposed to high altitudes, which are noted to impair female reproductive health.
Treatment was started 8 weeks following ovariectomy.
Effect of three different cultivars of Lepidium meyenii (Maca) on learning and depression in ovariectomized mice
About the Study
Type of study: Animal study, 21 days
Population: 3-month-old, ovariectomized mice, Swiss strain
Aim of the study: To assess the effect of yellow, red, and black maca on cognitive function and depression in ovariectomized (OVX) mice.
Maca Details
Species: Lepidium meyenii
Source of maca: Not stated
Location where maca was grown: Carhuamayo, Junín
Agricultural methods used: not stated
Part of maca used: Hypocotyls
Form of maca: Aqueous extract of yellow, red, and black maca
Dose: 1g/kg BW/day, oral administration
Outcomes
Results:
Black maca provided the most beneficial effects on latent learning, as measured by water finding task, particularly on trained mice though all phenotypes were effective for trained and non-trained mice (p<0.05)
The immobility time measured in the forced swimming test was decreased in the groups treated with the three colors of maca (yellow, red and black), suggesting is anti-depressant effects.
Other details:
The three colors of maca increased uterine weight of OVX mice, suggesting it is due to progestin-like effects.
Effect of chronic treatment with three varieties of Lepidium meyenii (Maca) on reproductive parameters and DNA quantification in adult male rats
About the Study
Type of study: Animal study, 84 days
Population: 3-month-old adult male rats, Holtzman strain
Aim of the study: To determine whether treatment with diverse varieties of maca (red, yellow, and black) affects daily sperm production (DSP), sperm counts in epididymal and vas deferens, and total DNA levels in testes.
Maca Details
Species: Lepidium meyenii
Source of maca: Not stated
Location where maca was grown: Carhuamayo, Junín
Agricultural methods used: Autumn harvest, dried and stored for 2 years
Part of maca used: Hypocotyls
Form of maca: Aqueous extract
Dose: 1g/kg BW, oral administration
Outcomes
Results:
Daily sperm production was similar between all treatment groups.
Black and yellow maca improved epididymal sperm count (p<0.05).
Black, yellow, and red maca improved sperm count in vas deferens (P<0.05).
DNA concentration in the testis was similar to all treatment groups.
"Maca seems to act as a modulator of sperm count at the reproductive tract level."
Effects of different varieties of Maca (Lepidium meyenii) on bone structure in ovariectomized rats
About the Study
Type of study: Animal study, 4 weeks
Population: 3-month-old ovariectomized rats, N=36
Aim of the study: To determine the effect of different varieties of maca (Lepidium meyenii) on bone structure in ovariectomized (OVX) rats
Maca Details
Species: Lepidium meyenii
Source of maca: Not stated
Location where maca was grown: Ninacaca, Pasco
Agricultural methods used: Not stated
Part of maca used: Hypocotyls
Form of maca: Hydroalcoholic, spray-dried extract
Dose: 64 mg/ml, containing 4.3 mg/kg polyphenols
Outcomes
Results:
Black and red maca reduced the negative effects of ovariectomy on bone health by increasing trabecular bone in the lumbar vertebrae.
Black and red maca reversed the effects of the ovariectomy on absolute weight of femur and femur width, while yellow maca did not have an impact.
The results of black and red maca were similar to the estradiol treated group.
Other details:
Polyphenol content was higher in spray-dried maca compared to pulverized powder, with the highest amounts in red maca, followed by yellow and finally black maca.
The authors suggest black and red maca can be an alternative treatment option for osteoporosis.
Photoprotection against the UVB-induced oxidative stress and epidermal damage in mice using leaves of three different varieties of Lepidium meyenii (maca)
About the Study
Type of study: Animal study
Population: 3-month-old male mice, Swiss strain, N=36
Aim of the study: To evaluate the photoprotective effect of the leaves of the three different varieties of maca (yellow, black, and red) against the UVB-induced oxidative stress and epidermal damage in the skin of mice.
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: Dried leaves
Form of maca: Not stated
Dose: 200 microliter per treatment, concentrated to 1 mg pyrogalol/ml
Outcomes
Results:
Red, yellow, and black maca demonstrated UVA/UVB absorptive properties and antioxidant activity.
Treatment of the three colors had a similar effect to the group treated with sunscreen, SPF 60.
Highest activity was from red maca, followed by black and then yellow.
Each of the three colors prevented the development of sunburns, epidermal hyperplasia, and leukocytic infiltration.
Black maca showed the highest superoxide dismutase levels and higher catalase levels in the skin.
N-Butanol and Aqueous Fractions of Red Maca Methanolic Extract Exerts Opposite Effects on Androgen and Oestrogens Receptors (Alpha and Beta) in Rats with Testosterone-Induced Benign Prostatic Hyperplasia
About the Study
Type of study: Animal study, 21 days
Population: 3-month-old, male rats, Holtzman strain, N=36
Aim of the study: To determine the effects of methanolic red maca extract and its n-butanol and aqueous fractions on expression of androgen and oestrogen receptors in rats with testosterone enanthate-induced benign prostatic hyperplasia (BPH)
Maca Details
Species: Lepidium meyenii
Source of maca: Not stated
Location where maca was grown: Junin, Peru
Agricultural methods used: Not stated
Part of maca used: Hypocotyls
Form of maca: methanolic extract and its n-butanol and aqueous fraction
Dose: 36.1 mg of methanolic extract, 4.0 mg of butanol fraction, or 32.5 mg aqueous fraction per day
Outcomes
Results:
Red maca as an extract and butanol fraction reduced prostate weight in a similar manner to Finasteride.
Aqueous fraction increased androgen and ERα receptors.
All maca groups restored the expression of ERβ.
"In conclusion, butanol fraction of red maca reduced prostate size in BPH by restoring expression of ERβ without affecting androgen receptors and ERα."
Lepidium meyenii Walp (red maca) Supplementation Prevents Acrylamide-Induced Oxidative Stress and Liver Toxicity in Rats: Phytochemical Composition by UHPLC-ESI-MS/MS
About the Study
Type of study: Animal study, 4 weeks
Population: Male rats, Sprague-Dawley strain, N=42
Aim of the study: To identify red maca’s phytochemical composition using UHPLC–ESI–MS/MS, and evaluate its effects on acrylamide-induced oxidative stress.
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: Hypocotyls
Form of maca: Lyophilized aqueous extract
Dose: 1 and 2g/kg BW
Outcomes
Results:
Red maca administration:
Prevented (p<0.001) an increase in MDA levels in all tissues
Significantly (p<0.001) lowered levels of ALT and AST
Prevented oxidative stress and liver toxicity caused by acrylamide.
Further, twenty-five secondary metabolites were identified in the red maca including carbolines, alkamides, fatty acids, and macamides, "...which are probably involved in their antioxidant protective role."
Other details:
Administration of acrylamide (a by-product of cooking that is a known carcinogen) significantly increased (p<0.001) malondialdehyde (MDA) levels in erythrocytes, brain, and liver.
Dose-response effect of Red Maca (Lepidium meyenii) on benign prostatic hyperplasia induced by testosterone enanthate
About the Study
Type of study: Animal study
Population: 3-month-old, adult male rats, Holtzman strain
Aim of the study: To determine the effect of a freeze-dried aqueous extract of the red variety of Lepidium meyenii (Red Maca) on testosterone-induced benign prostatic hyperplasia (BPH) in adult rats
Maca Details
Species: Lepidium meyenii
Source of maca: Not stated
Location where maca was grown: Carhuamayo, Junin, Peru
Agricultural methods used: Not stated
Part of maca used: Hypocotyls
Form of maca: Freeze-dried aqueous extract
Dose: 0.01, 0.05, 0.1, and 0.5 g/kg BW, orally administration, once daily
Outcomes
Results:
Red maca reduced prostate weight in BPH induced rats in a dose-response fashion (p<0.05).
Doses of 0.1 and 0.5 g/kg body weight resulted in higher reductions in prostate weight compared to Finasteride (p<0.05).
Other details:
Freeze-dried aqueous red maca in various doses was used and compared against Finasteride as the control. Benign prostatic hyperplasia (BPH) was induced with testosterone enanthate (TE).
Effect of red maca (Lepidium meyenii) on INF-γ levels in ovariectomized rats
About the Study
Type of study: Animal study,
Population: Adult ovariectomized rats
Aim of the study: To compare the effect of different doses of red maca on gamma interferon (IFN-γ) levels in ovariectomized rats (OVX).
Maca Details
Species: Lepidium meyenii
Source of maca: Unknown, abstract only
Location where maca was grown: Unknown, abstract only
Agricultural methods used: Unknown, abstract only
Part of maca used: Unknown, abstract only
Form of maca: Extract
Dose: 2.15, 4.3, and 8.6 mg polyphenols/body weight kilogram
Outcomes
Results:
Both estradiol and red maca reversed the effect of ovariectomy on the IFN-γ levels, increasing levels (p<0.05).
Article is in Spanish, data reported on the Abstract only, which is provided in English.
Acceptability, Safety, and Efficacy of Oral Administration of Extracts of Black or Red Maca (Lepidium meyenii) in Adult Human Subjects: A Randomized, Double-Blind, Placebo-Controlled Study
PMID: 27548190
About the Study
Type of Study: Human study, 12-week, double-blind, placebo-controlled trial
Population: N=175, men and women living in low altitudes (LA) 150 meters above sea level in Lima, Peru, and high altitudes (HA) 4,340 meters above sea levels in Cerro de Pasco, Peru; 18 subjects withdrew
Aim of the study: To compare the efficacy, acceptability, and safety of oral administration of spray-dried extracts of black maca, red maca, or placebo, in adults living in low and high altitudes of Peru
Maca Details
Species: Lepidium meyenii
Source of maca: Enterprise A-1 del Perú, Industrial Comercial SAC prepared the finished product
Location where maca was grown: Peru
Agricultural methods used: Not stated
Part of maca used: Dried hypocotyls used to prepare the extracts
Form of maca: Spray-dried extract, standardized
Dose: 3 grams per day
Outcomes
Results:
About 50% of all participants reported an increase in sexual desire.
Effects on mood, energy, and CMS scores were better using red maca compared to black maca and placebo.
In the red maca group at weeks 8 and 12: 80% of all participants reported increased mood and 90% reported increased energy.
Higher quality of life was reported in both red and black maca groups (p<0.05)
Black maca reduced hemoglobin levels in HA participants.
In HA, black maca reduced glucose levels in weeks 8 and 12 (p<0.05), red maca reduced glucose in week 8 (p<0.01)
Systolic blood pressure was reduced in weeks 8 and 12 in the HA group using black maca (p<0.01)
Red maca reduced CMS scores in weeks 4 (p<0.05), 8 (p<0.01) and 12 (p<0.01).
Black maca reduced CMS scores in weeks 8 and 12 (p<0.05).
Other details:
Up to 4% reported a dislike of the taste of the products, but no other effects were reported.
The authors propose the differences in outcomes are likely due to the different compositional makeup of black and red maca colors.
Fatty acids and macamides were higher in black maca than in red maca.
GABA dominated in red maca.
Abbreviations: HA: high altitude; CMS: chronic mountain sickness