Black, Red and Yellow Maca: What Differs and What Was Tested

Black, red and yellow maca are colour types of one plant, Lepidium meyenii. In a controlled growing study, colour changed how much of each plant compound the root held, and in the one trial that compared colours, 175 adults' mood and energy scores improved with both black and red extract against placebo, more with red.^{1, 2} The colour claims for fertility, bone and memory come from rat and mouse studies. Nothing here ranks one colour; the Wellgard maca guide covers maca as a whole.

Evidence at a glance

• Trials: one randomised trial in people compared colours (black and red extract, 175 adults); two small black maca studies in athletes; growing and animal studies.
• Largest single trial: 175 adults, 3 g of black or red extract or placebo daily for 12 weeks (publicly funded).
• Strongest measured outcome: mood, energy and mountain-sickness scores improved more with red than with black extract; black lowered blood glucose.
• Not tested: yellow against black or red in people, or gelatinised against raw maca in any human trial.

Sources checked on 14 October 2026.

What are black, red and yellow maca, and how is maca grown?

Maca is a root of the cabbage family, grown for over 2,000 years at 4,000 to 4,500 m in the Peruvian Andes; some labels call it Lepidium peruvianum. A 2012 review counts 13 root colours in one highland district, from white to black.³ The roots are traditionally dried in the open until hard as stone, then boiled before eating, most often as a drink.³ Commercial maca is the same dried root, milled, gelatinised or extracted.

How do black, red and yellow maca differ?

In what they contain. In a controlled planting study in Peru, colour changed the levels of most plant compounds measured: lead-coloured roots were rich in glucosinolates, yellow in macaene and violet in macamides.¹ In the colour trial's extracts, black held more fatty acids and macamides and red more GABA.² Processing matters too: macamides are essentially absent from fresh root and form as it dries.⁴ A difference in content is not a difference in effect.

What did the one trial comparing black and red maca find?

It gave 175 Peruvian men and women, living at low or high altitude, 3 g of black or red maca extract or a placebo daily for 12 weeks.² Against placebo, both extracts improved mood, energy and health-status scores and lowered the chronic mountain sickness score; the authors report larger effects on mood, energy and mountain sickness with red, and similar quality-of-life responses to both. Black lowered blood glucose. Black, and less so red, lowered high haemoglobin in highlanders only. The full paper adds that desire scores with red differed from placebo at high altitude at week 12, not at low altitude. No serious adverse effects were reported. The trial was publicly funded; one author runs a small nutraceutical company.²

Two smaller studies tested black maca extract in athletes: 44 elite athletes over eight weeks with no comparison group, reporting fitness and inflammatory-marker changes (no external funding; two authors work for the seller of the product), and eight teenage female handball players who scored higher on shuttle-run and strength tests than on placebo after four weeks (no funding; one author works for the seller).^{5, 6} No black maca trial has measured erections, sperm or testosterone in men; see maca for men.

What do the animal studies say about each colour?

Most colour claims come from one Peruvian research group's work in rodents. In rats, black maca for 42 days was the only colour that raised sperm production and movement; red reduced prostate weight.⁷ In 36 rats whose ovaries had been removed, black and red maca for four weeks lessened the bone changes that followed.⁸ In mice given scopolamine, a drug that impairs memory, black maca extracts improved maze and avoidance scores.⁹ In mice with testosterone-induced prostate enlargement, red maca reduced prostate weight.¹⁰

Which maca colour did the men's and women's trials use?

Most do not name one. Two Czech semen trials used gelatinised yellow powder supplied by a Peruvian producer: 1.75 g a day in 20 healthy men (no funding statement) and 2.8 g a day in 50 men with fertility problems (university-funded).^{11, 12} A trial in 80 men over 40 used about 5 g of gelatinised powder a day, colour not stated (publicly funded; three authors list company affiliations).¹³ Women's trials used 3.5 g of powdered maca in 14 postmenopausal women and 3 g of maca root in 45 women on SSRI or SNRI antidepressants, neither naming a colour.^{14, 15}

What does gelatinised maca mean, and is it easier to digest?

Gelatinised maca is dried root rehydrated, briefly pressure-heated in moist conditions and dried again. The 2015 Czech trial paper says this process "decomposed the starch component and increased the digestibility of the product".¹¹ It echoes the Andean habit of boiling maca, which highlanders advise because fresh maca may have adverse effects, an idea not scientifically assessed.³ No trial has compared gelatinised with raw maca in people.

What is the difference between maca powder and extract, and what does "5,000 mg" on a label mean?

An extract is made by steeping maca root in water or alcohol and drying what dissolves. Labels give extracts a ratio (10:1) or an "equivalent to" figure: the weight of dried root the extract was made from, not the weight of maca in the capsule. So 500 mg of a 10:1 extract is "equivalent to 5,000 mg" of root but holds 500 mg of extract. Ratios differ between products, so compare root weight with root weight. The colour trial's methods state that 20 g of dried root made almost 3 g of its extract.² See how much maca the trials used.

Which maca colour is best?

No trial supports ranking the colours; the table gives what each has been tested for.

What does maca taste like, and how is it eaten?

In the Andes it is boiled and drunk, and highlanders eat more than 20 g of dried root a day.³ Powder is usually stirred into porridge, smoothies or warm milk. Maca is a cruciferous vegetable, a family the colour trial's authors note can taste bitter, yet only 0 to 4% of their participants disliked their daily sachet.²

What we don't know

• Yellow maca has not been compared with black or red in people.
• Gelatinised and raw maca have not been compared in any human trial, for effects or digestion.
• Whether colour differences in plant compounds change outcomes has been tested in one trial only.
• The animal findings on sperm, bone, memory and the prostate have not been tested by colour in people.

Frequently asked questions

Is red or black maca better for men?

No trial has compared them in men alone for desire, erections or sperm. The one comparison enrolled men and women and found larger mood and energy changes with red; in rats, black raised sperm production.^{2, 7} The men's trials are in maca for men.

Which maca do fertility trials use?

The two semen trials that name a colour used gelatinised yellow powder.^{11, 12} They measured sperm and hormones, not pregnancies; no colour has been tested for conception.

How long does black or red maca take to work?

The full colour-trial paper reports mood rising with both colours from week 1 at low altitude, measured to week 12; the athlete studies measured at four and eight weeks.^{2, 5, 6}

What is raw, organic or fermented maca?

None is a colour. Raw is dried root milled without cooking; organic describes how it was grown; we found no human trial of fermented maca. For any of them, heavy-metal testing is worth checking: maca grown near Peruvian mining areas has carried cadmium and lead above international food limits.¹⁶

Sources

1. Clément C. J Sci Food Agric 2010. Controlled planting study, Peru. PubMed 20355123
2. Gonzales-Arimborgo C. Pharmaceuticals 2016. Randomised trial, 175 adults, 12 weeks; publicly funded; one author runs a small nutraceutical company. PubMed 27548190
3. Gonzales GF. Evid Based Complement Alternat Med 2012. Narrative review. PubMed 21977053
4. Esparza E. Phytochemistry 2015. Laboratory and field drying study. PubMed 25817836
5. Lee E. Nutrients 2023. Uncontrolled study, 44 athletes, 8 weeks; no external funding; two authors work for the seller of the product. PubMed 37049458
6. Kang S. Food Nutr Res 2023. Placebo crossover, 8 players, 4 weeks per phase; no funding; one author works for the seller of the product. PubMed 38187794
7. Gonzales C. J Ethnopharmacol 2006. Animal study, rats, 42 days. PubMed 16174556
8. Gonzales C. Forsch Komplementmed 2010. Animal study, 36 rats, 4 weeks. PubMed 20616517
9. Rubio J. Food Chem Toxicol 2007. Animal study, mice, 35 days. PubMed 17543435
10. Gonzales GF. Andrologia 2008. Animal study, mice, 21 days. PubMed 18477205
11. Melnikovova I. Evid Based Complement Alternat Med 2015. Randomised pilot, 20 men, 12 weeks; maca supplied by a Peruvian producer; no funding statement. PubMed 26421049
12. Melnikovova I. Phytother Res 2021. Randomised trial, 50 men, 16 weeks; university-funded; maca supplied by a Peruvian producer. PubMed 34585449
13. Shin D. World J Mens Health 2023. Randomised trial, 80 men, 12 weeks; publicly funded; three authors list company affiliations. PubMed 36593713
14. Brooks NA. Menopause 2008. Randomised crossover, 14 women, 6 weeks per phase; a US public research grant is listed. PubMed 18784609
15. Dording CM. Evid Based Complement Alternat Med 2015. Randomised trial, 45 women, 12 weeks; publicly funded. PubMed 25954318
16. Orellana Mendoza E. Toxicol Rep 2021. Field study, mining-area districts, Peru. PubMed 34401355

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