Maca Root
Lepidium meyenii (Peruvian ginseng)
Evidence grade 2 of 5, Thin. Read how the Atlas grades evidence.
The written rationale for this grade is still being prepared.
- FDA
- Not FDA evaluated (dietary supplement)
Reference only. Not medical advice.
What can go wrong
Generally well tolerated as a food-grade tuber. High doses can cause GI upset. Contains goitrogenic glucosinolates, so caution with thyroid conditions, especially if consumed raw in large amounts.
This is something to take to a clinician. The Atlas can tell you what is known about maca root in general. It cannot tell you what is happening in your body, and the difference matters most for exactly the symptoms that bring people to this page.
A high-altitude Andean tuber traditionally used for fertility and energy. Human studies most consistently support an improvement in libido and possibly sperm parameters, but importantly they do NOT show a change in testosterone or other reproductive hormones. Maca is a clean example of why 'helps sexual function' and 'raises testosterone' are not the same claim.
Improves libido without changing testosterone, an important distinction.
What people take it for
These are the reasons people give for taking it. They are not effects it has been shown to have.
How it is supposed to work
The libido effect appears to be independent of the endocrine axis; controlled studies show improved sexual desire without measurable changes in testosterone, LH, or FSH. The active macamides/macaenes are thought to act through non-hormonal pathways that are not fully mapped.
Libido is not testosterone
Maca is frequently shelved among 'testosterone boosters,' but the clearest human evidence is for desire and sexual function with no hormonal change. Conflating the two is one of the most common category errors in the men's-supplement market.
What people get wrong
Often saidMaca raises testosterone
ActuallyNo. Human studies show improved libido with no change in testosterone or gonadotropins.
Who profits, and who pushes back
Wellness and sexual-health marketers
Sells this. Has a commercial interest in a product sold as this compound, as of July 2026.
Promoted widely for libido; some marketing improperly implies testosterone effects
How we got here
Maca has been cultivated in the high Peruvian Andes for thousands of years, valued for fertility (in livestock and humans), stamina at altitude, and as a food staple. It entered the global supplement market as 'Peruvian ginseng,' a marketing label unrelated to true ginseng.
- Pre-ColumbianAndean cultivation for fertility and stamina
- 2002Gonzales libido study clarifies non-hormonal effect
- 2000s-nowGlobal popularity as a libido and 'vitality' supplement
At a glance
- Origin
- Peruvian Andes, high altitude
- Active class
- Macamides, macaenes, glucosinolates
- Best-supported effect
- Libido (not testosterone)
- Color variants
- Yellow, red, black
What this entry does not yet cover
What follows is unfinished work on our side, not a finding about Maca Root. A short entry is not a safe entry.
- Cost and market. We have not documented what it sells for or who sells it.
- Supply chain. We have not mapped where it is made.
- Who uses it. We have not documented the user groups.
- What could change. No forward-looking summary yet.
- How it compares. We have not set it against the alternatives.
- Children and teenagers. We have not checked what is known about younger people.
- Where we land. We have not taken a position on this yet.
Sources
The studies below are named and described, but not linked. You cannot open them from here and check our reading against them, which means this page is our summary of the literature rather than a document you can verify. Weigh it accordingly until the links exist.
The studies that matter
Gonzales et al.2002
Maca improved sexual desire in men without changing serum testosterone, LH, FSH, or estradiol
Systematic reviewsvarious
Consistent libido signal; weak/absent hormonal effect; sperm-parameter improvements reported in some studies