Maca root has the strongest evidence for improving sexual desire in men, with noticeable effects starting around 8 weeks of daily use. It also shows promise for mild erectile dysfunction, sperm quality, and physical endurance. What makes maca unusual is that it achieves these effects without changing testosterone or other hormone levels, meaning it works through different pathways than most people assume.
Sexual Desire and Libido
The most consistent finding across maca studies is an increase in self-reported sexual desire. In one study, men taking maca reported improved libido after just 8 weeks compared to a placebo group, even though their testosterone levels stayed the same throughout. This is a key distinction: maca doesn’t appear to work by boosting testosterone. Whatever mechanism is responsible, it seems to operate independently of the hormonal system that most “male enhancement” supplements claim to target.
A study of trained male cyclists found that 14 days of maca supplementation improved self-reported sexual desire alongside endurance performance. The libido effect appears relatively consistent across studies, which is notable given how many supplements fail to show any real difference once a placebo is introduced.
Erectile Function
For men with mild erectile dysfunction, maca may offer a modest benefit. In a randomized, double-blind trial published in Andrologia, men taking maca for 12 weeks saw their erectile function scores improve by an average of 1.6 points on a standardized scale, compared to just 0.5 points in the placebo group. Both groups improved (which is common in sexual health trials due to the placebo effect), but the maca group improved roughly three times more.
A 2023 trial found similar results in men with age-related hormonal decline, showing reduced erectile dysfunction after 12 weeks of gelatinized maca root. The pattern across studies suggests maca is not a replacement for prescription treatments in moderate or severe cases, but it may help men with milder symptoms.
Fertility and Sperm Quality
Maca has been linked to improvements in semen quality and sperm motility, two factors that directly affect a man’s ability to conceive. Black maca, the rarest and most expensive variety, is specifically associated with fertility benefits. It’s considered the most potent of the three maca types (yellow, red, and black) and is sometimes recommended for men actively trying to improve reproductive health.
If fertility is your primary goal, black maca is the variety most often cited in this context, though it comes at a higher price point than the more common yellow variety.
Physical Performance and Energy
A pilot study had eight trained male cyclists complete a 40-kilometer time trial before and after 14 days of maca supplementation. All eight cyclists finished faster after taking maca, with the average time dropping from 57.6 minutes to 56.6 minutes. That’s roughly a one-minute improvement, which is meaningful in competitive endurance sports.
There’s a caveat, though. The improvement was significant compared to the cyclists’ own baseline times, but when compared directly to the placebo group (which also improved slightly), the difference wasn’t statistically significant. The study was small, with only eight participants, so it’s hard to draw firm conclusions. Still, the fact that every single participant got faster is suggestive, and many men report a general sense of increased energy when taking maca regularly.
It Doesn’t Change Your Hormones
One of the most important things to understand about maca is what it doesn’t do. A study published in the Journal of Endocrinology tested doses of 1.5 and 3.0 grams per day for 12 weeks in healthy men and found zero effect on testosterone, luteinizing hormone, follicle-stimulating hormone, or prolactin. None of these hormones changed at any point during the study.
This matters for two reasons. First, it means maca’s benefits on libido and sexual function aren’t driven by hormonal changes, which challenges how most people think about it. Second, it means maca is unlikely to cause the hormonal side effects associated with actual testosterone-boosting compounds. Memorial Sloan Kettering Cancer Center confirms that maca does not affect serum levels of major reproductive hormones in men, though they note it can interfere with testosterone lab tests (immunoassays), potentially producing inaccurate readings. If you’re getting bloodwork done, let your doctor know you’re taking it.
Dosage and How Long It Takes
Clinical trials have used doses ranging from 1.2 grams to 3.0 grams per day, and there’s no clear consensus on the ideal amount. A systematic review in the Journal of Men’s Health noted that the recommended dosage remains unclear, though most positive studies fall in the 1.5 to 3.0 gram daily range.
Timing expectations vary by outcome. Libido improvements have been reported as early as 8 weeks. Erectile function benefits typically show up around 12 weeks. The cycling performance study saw results after just 14 days, though that was a single small trial. A reasonable expectation is to give maca at least two months before evaluating whether it’s doing anything for you.
Choosing Between Yellow, Red, and Black
Maca comes in three color varieties, each with a different profile:
- Yellow maca is the most common and least expensive. It’s milder and often recommended as a starting point.
- Red maca is rarer, slightly more expensive, and contains higher levels of plant-based nutrients. It’s considered more stimulating than yellow.
- Black maca is the rarest and most intense. It’s the variety most associated with fertility, muscle building, and bone density in men.
For general use, including libido and energy, any variety can work since most clinical trials used standard maca without specifying color. If you’re specifically targeting fertility or want the strongest effects, black maca is the variety with the most relevant reputation, though it will cost more.
Safety Profile
Maca has a relatively clean safety record across clinical trials. It’s been consumed as a food in Peru for thousands of years, and the doses used in studies (up to 3 grams daily for 12 weeks) haven’t produced serious adverse effects. The main practical concern is its potential to interfere with testosterone blood tests, which could lead to misleading lab results. Men with hormone-sensitive conditions should be aware that while maca doesn’t appear to change actual hormone levels, its mechanism of action isn’t fully understood, and some caution is reasonable.