Maca is a root in the brassica (mustard) family, related to turnips and radishes, grown in the high Andes of Peru1. It has long been eaten there as a food and is sold elsewhere as dried powder, capsules or concentrated extract, often labelled by root colour.
Unlike many herbs aimed at men, maca is not usually sold for testosterone, and the research fits that: in a 12-week trial in healthy men, maca improved self-reported sexual desire while testosterone and oestradiol levels stayed the same2. Its effect on libido appears to work independently of sex hormones.
Maca research spans a range of products, from gelatinised maca powder to a dry root extract23, so it helps to check which form a study used when comparing results.
Does maca increase libido?
Trials report improved sexual desire in healthy men, with effects appearing after about eight weeks. A systematic review found positive results in three of four randomised trials of sexual function.
In a 12-week placebo-controlled trial, men aged 21 to 56 took maca (the trial used 1,500 mg or 3,000 mg a day) or placebo. Sexual desire improved with maca from eight weeks onwards, and the effect was not explained by changes in mood, anxiety or hormone levels2.
A 2010 systematic review found four randomised trials of maca for sexual function. Three reported benefits: in healthy men, in menopausal women and in men with erectile dysfunction; a fourth, in cyclists, did not show a difference. The reviewers called for more and larger trials1.
What have studies found on maca and erections?
In a trial of men with mild erectile dysfunction, maca improved erectile function scores more than placebo over 12 weeks. Men taking maca also reported better general and sexual wellbeing.
Fifty men with mild erectile dysfunction took a dry maca extract (the trial used 2,400 mg a day) or placebo for 12 weeks. Scores on the five-item International Index of Erectile Function rose by 1.6 points with maca versus 0.5 with placebo, and only the maca group reported improvements in physical and social wellbeing scores3.
If erections have changed, see a GP; there are established treatments such as PDE5 inhibitors, and regular cardio is worth a look too.
What have studies found on maca and sperm?
Five randomised trials have measured semen quality in infertile and healthy men, and results have varied between them. Researchers have called for larger studies.
A 2022 meta-analysis found that some trials reported improvements in sperm concentration or motility, while pooling the data did not show a significant difference in sperm concentration compared with placebo. The authors said more and larger trials were needed4.
If you are trying to conceive, a semen analysis gives useful information about where to focus, and lifestyle factors are a sensible place to start.
Common questions
Does maca increase testosterone?
Maca's research points to effects on desire rather than hormones. In a 12-week placebo-controlled study, men taking maca reported higher sexual desire while their testosterone and oestradiol levels stayed the same2.
How long does maca take to work?
In the libido trial, differences from placebo appeared after eight weeks2, and the erectile dysfunction trial ran for 12 weeks3. Shorter courses have been studied less.
Is maca safe?
Maca is widely eaten as a food in Peru, and concentrated supplements have been tested in a small number of trials1, so data on long-term use are still being gathered. Talk to a doctor before using it if you take regular medication, have a hormone-related condition or are having fertility investigations.
Read more on this
Supplement ingredients for men’s sexual health: what the research shows
Lifestyle factors that affect male fertility: a practical guide
Does cardio really improve erections? What the research says
Sources
- Shin BC, et al. Maca (L. meyenii) for improving sexual function: a systematic review. BMC Complement Altern Med. 2010;10:44. PubMed
- Gonzales GF, et al. Effect of Lepidium meyenii (MACA) on sexual desire and its absent relationship with serum testosterone levels in adult healthy men. Andrologia. 2002;34(6):367-372. PubMed
- Zenico T, et al. Subjective effects of Lepidium meyenii (Maca) extract on well-being and sexual performances in patients with mild erectile dysfunction: a randomised, double-blind clinical trial. Andrologia. 2009;41(2):95-99. PubMed
- Lee HW, et al. Maca (Lepidium meyenii Walp.) on semen quality parameters: A systematic review and meta-analysis. Front Pharmacol. 2022;13:934740. PubMed
Not medical advice. Written by Eric Stephens from the research cited above; not reviewed by a doctor. If something worries you, see a GP.