Know2eat

Maca

Lepidium meyenii

Herbs & Botanicals

What maca may help with

Ranked by how strong the human evidence is — best supported first.

Best supportedExercise performanceNot enough evidence· 2 sources

Then, in order

About Maca

The dried root of a high-altitude Andean brassica, eaten as a food in Peru and sold as a powder or extract. Yellow, red and black maca are different phenotypes with different reported effects.

Maca is marketed hard for libido, fertility and energy, and its trial literature is small, mostly Peruvian, and frequently connected to one research group. Reviews conclude the evidence is limited and of poor quality. It has also been the subject of adulteration concerns, and the sexual-performance supplement category as a whole has a documented record of undeclared prescription drugs.

Sold as
Root powder, Gelatinised powder, Extract capsule, Liquid extract
Standardised to
Sometimes standardised to macamides and glucosinolates; colour phenotype is often not stated — a product without this marker may not resemble what was studied.
Also known as
Peruvian ginseng, Maca root, Lepidium peruvianum

What the research used

The amounts, forms and durations published trials of Maca actually administered.

These are the amounts published trials administered — not a recommendation, and not a dose to copy. Trial participants were screened, supervised and given a characterised preparation. What is in a retail bottle is frequently not what was studied, and the amount that suits one person is not general advice.

  • Studied for Sexual desire and function

    1.5–3 g

    Not enough

    Dried root powder, divided doses · 6–12 weeks

    Trials are small, largely from one Peruvian group, with self-reported endpoints. Reviewers describe the evidence as limited and low quality.

  • Studied for Menopausal symptoms

    2–3.5 g

    Not enough

    Root powder capsules · 6–12 weeks

    A small number of trials with subjective symptom scales and short duration.

This is general information about food, not medical advice. It cannot diagnose, treat or replace guidance from a clinician who knows your history.

When it was taken

Each window says whether a trial compared it against an alternative, or whether it is convention and pharmacology. Most timing advice is the second kind.

None of the timings below were directly compared in a trial. They reflect how the research happened to dose, or what the pharmacology implies — which is not the same as a timing being better.

  • Morning

    Not enough

    Commonly taken in the morning because some users report it disturbs sleep. This is anecdote rather than a tested comparison.

    Timing was not directly compared. This reflects convention or how the compound behaves in the body, not a trial showing this window works better.

The evidence in depth

Best supported: Not enough

What each association actually rests on, and the papers behind it. A rating describes the state of the research, not how promising the supplement sounds. How we rate evidence.

Exercise performance

Muscle & Physical Performance
Not enough evidence

There is not enough human research to say maca affects endurance or energy. The few studies are very small and not replicated.

Not enough evidence. Not enough human research to say anything useful yet.

View the 2 sources

Deep research mode adds each paper’s own conclusion and stated limitations.

Menopausal symptoms

Women's Health
Not enough evidence

Evidence is limited for maca and menopausal symptoms. The trials are small, short and use subjective scales in a setting with a large placebo response.

Not enough evidence. Not enough human research to say anything useful yet.

View the 3 sources

Deep research mode adds each paper’s own conclusion and stated limitations.

Mood

Mental Wellbeing
Not enough evidence

Evidence is limited for maca and mood or wellbeing. Reported improvements come from small trials with subjective endpoints.

Not enough evidence. Not enough human research to say anything useful yet.

View the 3 sources

Deep research mode adds each paper’s own conclusion and stated limitations.

Things to know

Interactions, contraindications and dose limits, most serious first. Concentrated extracts interact with medication in ways the whole plant does not, so this section carries more weight here than it does on a food page.

  • Worth knowing

    Adulteration in sexual-performance products

    Supplements marketed for libido and erectile function are among the most frequently adulterated, with regulators repeatedly finding undeclared sildenafil and tadalafil analogues. Those are dangerous alongside nitrates and in heart disease.

  • Worth knowing

    Goitrogenic glucosinolates

    Maca is a brassica and contains glucosinolates, which can affect thyroid function when iodine intake is low. Traditional preparation involves cooking or gelatinising the root, which raw powders skip.

  • Worth knowing

    Hormone-sensitive conditions

    Despite claims that maca is non-hormonal, effects on hormone-sensitive conditions are not established, and caution is warranted in breast, uterine and prostate cancer.

  • Avoid

    Pregnancy

    Maca is eaten as a food in Peru, but concentrated supplement doses have not been studied in pregnancy or breastfeeding.

Evidence ratings on this page: 3 not enough evidence.

Supplements are sold in the US without pre-market review of efficacy or safety. Nothing on this page is a recommendation to take Maca, or a dose to follow.