Updated August 2026Evidence-Based

Maca Root: Benefits, Dosage and Side Effects

Also known as: Lepidium meyenii, Peruvian ginseng, Maca root

Illustration representing Maca, the ingredient this guide covers

Maca is a Peruvian root vegetable sold across libido, energy and fertility products. Its most interesting finding is a negative one: the trials that show an effect on sexual desire also show that testosterone and oestradiol do not move. Whatever maca does, it does not do it hormonally, which makes the testosterone-booster positioning it is often given straightforwardly wrong.

Maca: products that state their dose

Research on maca generally uses 1,500 mg/day. These are the products we found that put an amount on the label, so you can check them against it. Sorted by whether they reach that figure, then by how many people have rated them.

Prices and ratings were recorded when this page was last updated and change often; the figure on Amazon is the one that counts. As an Amazon Associate we earn from qualifying purchases, at no extra cost to you. Nothing on this list is paid placement: it is ordered on stated dose and rating volume, and we earn the same on all of it.

How Maca Works

Not established. Macamides and glucosinolates are the usual candidates, with proposed action on central neurotransmission rather than on the endocrine system. The absence of hormonal change in trials that still reported behavioural change is the strongest clue that the mechanism is central rather than gonadal.

Benefits

  • Sexual desire: a 12-week randomised trial found improvement from week 8 onward, independent of serum testosterone and oestradiol.
  • Antidepressant-induced sexual dysfunction: a dose-finding pilot reported improvement on the ASEX libido item, with the higher dose performing better.
  • Semen parameters: a meta-analysis of trials found improvements in sperm concentration and motility, on a small evidence base.
  • Menopausal symptoms: some benefit in small trials of postmenopausal women; the systematic review that covers this area is explicit that the evidence base is too small for firm conclusions.

Research Summary

Gonzales 2002 for sexual desire without hormonal change, Dording 2008 for antidepressant-induced sexual dysfunction, and the Shin 2010 systematic review, which found four eligible randomised trials and concluded the evidence was limited by trial number, sample size and methodological quality. That honest summary has not changed much.

Recommended Dosage

Min effective dose

1,500 mg/day

Max safe dose

3,000 mg/day

1.5-3 g/day of dried root powder, the range used in the trials. The dose-finding study for antidepressant-induced sexual dysfunction compared 1.5 g with 3 g and favoured 3 g. Effects on desire took about 8 weeks to appear, so a two-week trial tells you nothing.

Side Effects

Well tolerated in trials. Some people report GI discomfort or difficulty sleeping when taking it late in the day. As a brassica it contains glucosinolates, so people with thyroid conditions or low iodine intake may prefer gelatinised maca and should mention it to a prescriber.

Interactions

No well-documented drug interactions. Because it is hormonally inert in the trials conducted so far it does not carry the interaction profile of an actual hormonal agent, but that also means it should not be relied on where a hormonal effect is what is needed.

Best Supplements Containing Maca

Frequently Asked Questions

Medical Disclaimer

The content on this page is for informational purposes only and is not intended as medical advice, diagnosis, or treatment. Always consult your physician or qualified healthcare provider before starting any new supplement regimen. Individual results may vary.

Sources & References

  1. Gonzales GF et al. 2002. Maca and sexual desire, with no relationship to serum testosterone. Andrologia.
  2. Shin BC et al. 2010. Maca for improving sexual function: a systematic review. BMC Complement Altern Med.
  3. Dording CM et al. 2008. Dose-finding study of maca root for SSRI-induced sexual dysfunction. CNS Neurosci Ther.