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Yellow Maca

The research on yellow maca is limited in both animals and humans, compared to red and black maca, despite the high distribution of this color of maca. Its benefits include improving physical endurance and reproductive health, 

September 2021

Evaluation of the effect of Lepidium meyenii Walpers in infertile patients: A randomized, double-blind, placebo-controlled trial

Human study, N=50 infertile men

PMID: 34585449


Summary of Findings:


  • 2.8 grams per day of yellow maca was studied for 16 weeks. 

  • Yellow maca increased sperm count by 15%, sperm concentration by 40%, and a significant decrease of free testosterone by 27% was observed.

  • Stimulation of sperm quality may happen by a non-steroidogenic mechanism since free testosterone decreased in the maca treated group, possibly due to secondary metabolites including macamides, macaenes, and other lipid fractions. 

May 2019

Chemical Analysis of Lepidium meyenii (Maca) and Its Effects on Redox Status and on Reproductive Biology in Stallions

Animal study, stallions

PMID: 31126050

Summary of Findings:


  • Yellow maca was orally fed and studied for its biological effects on stallions for antioxidant activity and semen quantity and quality.

  • 88 compounds were identified in yellow maca including alkaloids, macamides, macaenes, and glucosinolates. 

  • A progressive increase in antioxidant capacity was observed through day 60, positively impacting redox status.

  • Total sperm count, sperm concentration, and ejaculate volume increased with the administration of yellow maca. 

November 2017

Aqueous extract of yellow maca (Lepidium meyenii) improves sperm count in experimental animals but response depends on hypocotyl size, pH and routes of administration

Animal study, male mice

PMID: 29160562

Summary of Findings:


  • The effects of aqueous extract of yellow maca from different hypocotyl sizes, grown under different pH conditions and using two different routes of administration were studied.

  • Sperm count was higher in mice receiving yellow maca from the larger hypocotyl sizes.

  • The higher pH content of yellow maca reduced sperm count. 

  • Oral administration of aqueous extract of yellow maca was the only effect route. 

  • "In conclusion, the larger size of hypocotyls presented the best biological effect, and the low pH in the extract and the transformation after gastrointestinal passage are both important for its biological action."

September 2016

Effect of butanolic fraction of yellow and black maca (Lepidium meyenii) on the sperm count of adult mice

Animal study, male mice

PMID: 27681648

Summary of Findings:


  • Yellow and black maca were studied.

  • Yellow maca had better antioxidant capacity compared to black maca. 

  • Total phenolic content was better in the methanolic fraction than in the aqueous fraction of both yellow and black maca, though it was higher in black maca compared to yellow. 

  • Butanoic fraction of yellow maca had higher antioxidant capacity compared to aqueous fractions of yellow maca. 

  • Methanolic extract of yellow maca resulted in higher daily sperm production compared to methanolic extract of black maca. 

September 2015

Effect of Lepidium meyenii Walp. on Semen Parameters and Serum Hormone Levels in Healthy Adult Men: A Double-Blind, Randomized, Placebo-Controlled Pilot Study

Human study, N=20, ages 20-40

PMID: 26421049

Summary of Findings:


Yellow maca was taken daily for 12 weeks at a dose of 1.75 grams by healthy men.


Yellow maca consumption resulted in multiple improvements of semen parameters

  • Increase of sperm count by 20%

  • Increase of sperm concentration by 14%

  • Improved sperm motility by 14%

  • Improved semen volume by 9%

  • Enhanced morphology of sperm by 21%

  • No changes in hormone levels were observed.


July 2011

Photoprotection against the UVB-induced oxidative stress and epidermal damage in mice using leaves of three different varieties of Lepidium meyenii (maca)

Animal study, male mice

PMID: 21781063

Summary of Findings:


  • Red, yellow, and black maca demonstrated UVA/UVB absorptive properties and antioxidant activity.

  • 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. 

  • Yellow maca showed higher catalase levels in the skin, as did black maca.

February 2008

Hypocotyls of Lepidium meyenii (maca), a plant of the Peruvian highlands, prevent ultraviolet A-, B-, and C-induced skin damage in rats

Animal study, male rats

PMID: 18201354

Summary of Findings:


  • Two yellow maca extracts (boiled and non-boiled) were studied

  • The boiled extract had a better effect compared to the non-boiled extract on skin protection from UV rays, though both provided protection.

  • Topical treatment of maca reduced skin damage by UVB in a dose dependent manner. 

August 2007

Effect of chronic treatment with three varieties of Lepidium meyenii (Maca) on reproductive parameters and DNA quantification in adult male rats

Animal study, male rats

PMID: 17683465

Summary of Findings:


  • Black and yellow maca improved epididymal sperm count

  • Black, yellow, and red maca improved sperm count in vas deferens.

  • "Maca seems to act as a modulator of sperm count at the reproductive tract level."

June 2006

Effect of three different cultivars of Lepidium meyenii (Maca) on learning and depression in ovariectomized mice

Animal Study, ovariectomized mice

PMID: 16796734

Summary of Findings:


  • Yellow, black, and red maca were studied

  • Black maca provided the most beneficial effects on latent learning, particularly on trained mice though all phenotypes were effective for trained and non-trained mice (p<0.05)

  • All varieties demonstrated anti-depressant effects.

May 2005

Lepidium meyenii (Maca) increases litter size in normal adult female mice

Animal study, female mice

PMID: 15869705

Summary of Findings:


  • Aqueous extract of lyophilized yellow maca was given to assess various fertility parameters of female mice. 

  • Implantation sites and reproductive indexes were similar in the yellow maca and control groups. 

  • Yellow maca group had significant increases litter size likely due to a reduction in embryo resorption, confirming "...the traditional uses of Maca to enhance female fertility."

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