The short answer
Black maca benefits in people are modest. In a 12-week placebo-controlled trial, black maca extract beat placebo on quality-of-life scores, with less certain gains in energy and mood, where red maca did better. It didn’t beat placebo for libido. Testosterone didn’t change in trials that measured it, and black maca’s sperm and memory findings come from rodents.
Black maca benefits at a glance
This table separates human trials of black maca from human trials of other or unnamed colors and from rodent studies.
| Possible benefit | Studied in people? | Black maca specifically? | What was found |
|---|---|---|---|
| Quality of life, energy and mood | Yes, 175 adults, with placebo | Yes | Quality of life better than placebo; energy and mood gains less certain; red maca did better |
| Libido (black maca) | Yes, same trial | Yes | No better than placebo |
| Libido (maca, color not stated) | Yes, small trials | Not stated | More desire in healthy men at 8 and 12 weeks in one trial; evidence rated limited |
| Erectile function | Yes, two trials (50 and 80 men) | Not stated | Better scores than placebo |
| Sperm and fertility | Yes, five trials | Three yellow, two not stated | No significant effect on sperm concentration; black maca’s edge seen only in rats |
| Testosterone | Yes | Not stated | No change in the trials that measured it |
| Exercise and inflammation | Yes, 41 male athletes, no placebo | Yes | Lower CRP, mixed fitness results; preliminary |
| Memory and learning | No, mice only | Yes | Better memory in mice; no human trial found |
| Menopause symptoms | Yes, very small trials | Not stated | Too limited for firm conclusions |
Only two human studies in this table clearly used black maca. The rest used yellow maca or didn’t say.
What black maca is
Maca (Lepidium meyenii) is a plant grown above 4,000 m in Peru and eaten as food in the central Andes for centuries. The edible part is the hypocotyl, an underground tuber similar to a radish or turnip. It comes in several colors, and black maca is the dark type. Today it’s sold as powder, capsules, tablets or gummies and promoted for libido, fertility and energy. The trials below used maca powder or extracts, not gummies. For more on the plant, see what black maca is and where it comes from.
We buy our black maca powder in Peru from brands such as Ecoandino, Inkanat and Kera Superfood. Some are sold as gelatinized and some don’t say.
Black maca benefits for men
Libido and sexual function
A 2010 systematic review found four small randomized trials with 131 people and rated the evidence for sexual function as limited. In one, 57 healthy men taking 1.5 or 3 g a day of gelatinized maca, color not stated, reported more desire than men on placebo at 8 and 12 weeks.
The only trial that tested black maca for libido doesn’t support it. In the 2016 study in Lima and Cerro de Pasco, only red maca beat placebo for sexual desire, only at high altitude and only at week 12, and the authors called that effect modest. Black maca didn’t beat placebo at either site.
For erections, the data are small and not color-specific. In a trial from the 2010 review, 50 men with mild erectile dysfunction took 2.4 g a day for 12 weeks, and their IIEF-5 erectile function score rose about 1.1 points more than with placebo. A 2023 double-blind trial gave Korean men over 40, with symptoms of age-related low testosterone but normal levels, about 5 g a day of gelatinized maca or placebo for 12 weeks. In the 80 who finished, erectile function and aging-symptom scores improved more with maca. The color isn’t named.
Sperm and fertility
A 2022 meta-analysis reviewed five randomized trials in healthy and infertile men taking 1.75–5 g a day for 12–16 weeks. In the pooled analysis, maca didn’t significantly raise sperm concentration versus placebo, motility results were mixed, and the authors called the trials too few and too small for firm conclusions. Three used gelatinized yellow maca, and two didn’t name a color.
Black maca’s reputation for sperm comes from rat studies, cited in the same review, where it looked more helpful than red or yellow for sperm motility. No human trial we know of has compared colors for sperm.
Testosterone
Maca doesn’t appear to raise testosterone. In the 2023 Korean trial, total and free testosterone didn’t differ from placebo after 12 weeks. LiverTox, an NIH database, describes a trial in 56 men taking 1.5 or 3 g a day for up to 12 weeks whose sex hormone levels didn’t change. Neither says the maca was black, and there isn’t enough research in people to say black maca acts differently.
Energy, mood and exercise
This is where black maca has its best human data, and it’s still thin. The 2016 trial randomized adults aged 18–65 to 3 g a day of black maca extract, red maca extract or placebo for 12 weeks, and 175 finished. The clearest result for black maca was quality of life, which beat placebo from week 4 in Lima, at sea level, and at weeks 8 and 12 in Cerro de Pasco, at 4,340 m. The authors also report more energy and better mood than placebo with black maca in Lima, but their tests compared all three groups at once, so they don’t show black maca beating placebo on its own. In Cerro de Pasco, energy didn’t differ from placebo. Red maca beat black on mood and energy. Note that the product was a spray-dried extract, not plain powder, and one author manages a small nutraceutical company.
For athletes, a 2023 Korean study gave 44 male elite athletes two 2,500 mg capsules of concentrated black maca extract a day for 8 weeks, and 41 appear in the results. C-reactive protein, an inflammation marker, fell significantly in two of the three groups (from 0.08 to 0.02 mg/dL in racket-sport players). Fin swimmers gained about 4 kg of grip strength, and their long jump rose from 197.8 to 222.1 cm. Times in a 10 m shuttle run got slower in all three groups. There was no placebo or control group, and the authors call the results preliminary. Some sites quote the dose as 2.5–3 g a day, but the paper describes 5 g of extract.
Black maca benefits for women
Can women take black maca? Women were part of the 2016 trial, in similar proportions in each group, and no serious side effects were reported. But results weren’t reported by sex, so the trial can’t show how women responded on their own.
For menopause, the human data use maca of unstated color. In a small crossover trial in 16 postmenopausal women, included in the 2010 review, sexual dysfunction scores improved with maca. In a later crossover trial of 29 postmenopausal women described by LiverTox, sexual dysfunction scores and hormone levels didn’t change. LiverTox also notes a review of four menopause trials, all favorable but too limited for firm conclusions. No trial we could find tested black maca for menopause, female hormones or women’s fertility.
What black maca hasn’t been shown to do
LiverTox says none of maca’s promoted effects have been proven in rigorously controlled human trials. Some popular claims have even less behind them:
- Memory and focus. Black maca’s memory results come from studies in mice, not people. Calling it a “nootropic” goes beyond the data.
- Hormone balance. Testosterone didn’t differ from placebo in the 2023 Korean trial, and hormone levels didn’t change in trials in men and in postmenopausal women described by LiverTox. None of them showed maca balancing hormones.
- Weight gain, curves or hair. We found no trial of maca of any color for these.
- Prostate health. Red maca reversed induced prostate enlargement in a study in mice. In the 2023 Korean trial in men over 40, urinary symptom scores improved more with maca of unstated color than with placebo, and PSA didn’t change. We’re not aware of any black maca trial for the prostate.
How black maca is taken in studies
These are amounts used in studies, not a recommendation. Extracts are more concentrated than powder, so the grams aren’t directly comparable.
| Study | Form | Amount | Length |
|---|---|---|---|
| 2016 trial, adults in Peru (black or red) | Spray-dried extract | 3 g a day | 12 weeks |
| 2023 study, male athletes (black) | Concentrated extract, two 2,500 mg capsules | 5 g a day | 8 weeks |
| 2023 trial, men over 40 (color not stated) | Gelatinized powder in capsules | About 5 g a day | 12 weeks |
| Trials in the 2010 sexual function review (color not stated) | Dried or gelatinized maca | 1.5–3.5 g a day | 2–12 weeks |
| Trials in the 2022 sperm meta-analysis (mostly yellow) | Mostly gelatinized maca | 1.75–5 g a day | 12–16 weeks |
Most trials measured results at 8–12 weeks. We found no study comparing morning and evening use. For more on amounts, see how much black maca people take.
How black maca might work isn’t known. The 2016 trial found more macamides, a group of compounds, in the black extract than in the red, but none of these trials tested how they act. So does black maca work? A little, mainly for quality of life, in one trial.
Raw or gelatinized?
Raw maca powder is the dried root, ground. Gelatinized maca is heat-treated before milling, and it was used in the 2023 trial in older men and in four of the five sperm trials. We haven’t seen a trial comparing the two forms of black maca.
Who should be careful with black maca
The 2016 black maca trial reported no serious side effects, and blood pressure didn’t differ from placebo with either extract. The 2023 trial in older men recorded two cases of mild stomach upset. LiverTox describes side effects as uncommon and mild, mostly digestive symptoms and headaches, and rates maca an unlikely cause of liver injury.
Some people should talk to a doctor first or skip it:
- Pregnancy and breastfeeding. Pregnant women were excluded from the 2016 trial, and we found no safety data for pregnancy or breastfeeding. Skip it, or ask your doctor first.
- Medicines and health conditions. If you take prescription medicines or have a hormone-sensitive condition, ask your doctor before using it. The trials were short and small and say little about interactions.
- Product quality. Buy from sellers who state the origin and batch.
More detail is in our guide to black maca side effects.
Black maca vs red and yellow maca
The 2016 study is the only human trial we found that compared colors directly, and red maca beat black on mood and energy. Black maca’s reputation as the “male” color rests on rat studies of sperm. For a full side-by-side, see how black and red maca compare.
Frequently asked questions
Does black maca really work?
Modestly, and only for some things. One placebo-controlled trial of 175 adults found better quality-of-life scores with black maca than with placebo, and less certain gains in energy and mood, where red maca did better. It didn’t beat placebo for libido. There’s no good human evidence for black maca on sperm, testosterone or memory.
Is black maca good for women?
There’s little women-specific evidence. Women took part in the main black maca trial, but results weren’t reported by sex. Menopause trials used maca of unstated color and were too small for firm conclusions. Nothing shows that black maca balances female hormones or helps women’s fertility.
How long does black maca take to work?
Most trials measured results after 8 to 12 weeks. In the 2016 trial, people at sea level taking black maca had better quality-of-life scores than the placebo group from week 4. The authors also report more energy from week 2, but without a separate test against placebo. These are group averages from one study, not a timeline you can count on.
Can I take black maca every day?
The trials gave maca daily for up to 16 weeks, and the side effects reported were mostly mild, such as stomach upset or headache. There’s little data on daily use beyond a few months, and longer use hasn’t been studied. LiverTox rates maca an unlikely cause of liver injury.
Does black maca make you gain weight or curvier?
We found no trial that tested black maca, or maca of any color, for weight gain, weight loss, belly fat, bigger hips or a curvier figure. Claims that it makes you “thicker” or curvier aren’t backed by any study we could find, so the research doesn’t support using it for that.
Is black maca the best maca for men?
Not on current human evidence. No trial we know of has compared black and yellow maca in men. Black maca looked better for sperm motility in rats, but human sperm trials, mostly with yellow maca, found no significant effect on concentration. In the one trial comparing black and red maca, red came out ahead.
Shop Peruvian black maca powder
If you’d like to try it, we buy black maca powder in Peru and ship it from Lima to the US, UK, Canada, Australia and New Zealand.
Sources
- Gonzales-Arimborgo C, Yupanqui I, Montero E, et al., 2016. 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. Pharmaceuticals.
- Shin BC, Lee MS, Yang EJ, et al., 2010. Maca (L. meyenii) for improving sexual function: a systematic review. BMC Complementary and Alternative Medicine.
- Lee HW, Lee MS, Qu F, et al., 2022. Maca (Lepidium meyenii Walp.) on semen quality parameters: a systematic review and meta-analysis. Frontiers in Pharmacology.
- Lee E, Park M, Kim B, et al., 2023. Effect of black maca supplementation on inflammatory markers and physical fitness in male elite athletes. Nutrients.
- Shin D, Jeon SH, Piao J, et al., 2023. Efficacy and safety of maca (Lepidium meyenii) in patients with symptoms of late-onset hypogonadism: a randomized, double-blind, placebo-controlled clinical trial. World Journal of Men’s Health.
- National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), 2019. Maca. LiverTox: Clinical and Research Information on Drug-Induced Liver Injury.
