Maca
Summary
Maca has small, low-quality trials behind it. Systematic reviews found limited evidence for sexual function (4 RCTs, 131 people) and menopausal symptoms, and no clear effect on sperm concentration across 5 RCTs (grade D). Trials used 1.75–5 g/day of root powder for 6–16 weeks and did not track side effects systematically.
Key facts
- Dried root of Lepidium meyenii, a brassica grown in the high Andes; sold as raw or gelatinized powder[1][3]
- Sexual function: limited, mixed evidence (D); sperm concentration: no clear effect (D); mood and blood pressure after menopause: one small trial (D)[1][3][5]
- 4 graded human outcomes on this page
- October 10, 2026
How it works
ProposedHow maca might act is unknown. In a crossover trial in postmenopausal women it did not change estradiol, FSH, SHBG or TSH, so a direct hormone effect looks unlikely.[5]
What the human research says
Human trials only, one row per outcome. The form column shows what each trial actually tested. Grades follow our evidence-grading policy.
At a glance: strongest evidence per outcome
| Outcome | Grade | Effect | Strongest evidence | Rows |
|---|---|---|---|---|
| Fertility | Grade D | No effect | Meta-analysis of 5 trials · n = 244 · 2022 | 1 row |
| Sexual function | Grade D | Mixed | Systematic review of 4 trials · n = 131 · 2010 | 2 rows |
| Menopause | Grade D | Improved | Crossover RCT · n = 29 · 2015 | 1 row |
Every graded row
| Outcome | Effect | Grade | Best evidence | PMID |
|---|---|---|---|---|
| Sperm concentration and semen quality | No effect | Grade D | Meta-analysis · n = 244 · 2022 Healthy and infertile men in 5 RCTs (Europe, Korea, Panama) Form: maca root powder (some gelatinized or fermented) · Dose: 1.75–5 g/day · Duration: 12–16 weeks Pooled sperm concentration did not differ from placebo (WMD 2.22, 95% CI −2.94 to 7.37). Other semen measures moved in both directions across trials. | 36110519 (opens PubMed)Source [3] |
| Sexual function and desire | Mixed | Grade D | Systematic review · n = 131 · 2010 Healthy men, menopausal women, cyclists and men with erectile dysfunction in 4 RCTs Form: maca root preparations · Dose: Varied across trials · Duration: Varied across trials Two RCTs found better sexual function or desire, one found no effect in cyclists, and one found better erectile function scores. The reviewers judged the evidence too limited for firm conclusions. | 20691074 (opens PubMed)Source [1] |
| Antidepressant-related sexual dysfunction in women | Mixed | Grade D | RCT · n = 45 · 2015 Women whose depression had remitted on an SSRI or SNRI (US) Form: maca root · Dose: 3.0 g/day · Duration: 12 weeks Remission of sexual dysfunction was numerically higher with maca (30% vs 20% on one scale), mainly in postmenopausal women. Maca was well tolerated. | 25954318 (opens PubMed)Source [6] |
| Depression scores and diastolic blood pressure after menopause | Improved | Grade D | Crossover RCT · n = 29 · 2015 Postmenopausal women in Hong Kong Form: maca root powder · Dose: 3.3 g/day · Duration: 6 weeks per phase Depression scores and diastolic blood pressure fell with maca; estradiol, FSH, SHBG, TSH, lipids and glucose did not change. | 24931003 (opens PubMed)Source [5] |
Forms
| Form | Elemental % | Absorption (human data) | GI tolerance | Studied for |
|---|---|---|---|---|
| Gelatinized maca root powder (starch removed by heat processing) | Varies[3] | No human absorption data in our sources.[3] | Not systematically assessed in trials.[3] | Semen-quality trials (e.g. 1.75 g/day) |
| Raw dried maca root powder or capsules | Varies[4] | No human absorption data in our sources.[4] | Two of 50 men dropped out for possible adverse events (starch intolerance, colitis diagnosis) in a 16-week trial.[4] | Infertility trial (2.8 g/day as seven 400 mg capsules) |
| Fermented maca | Varies[3] | No human absorption data in our sources.[3] | No specific tolerance data in our sources.[3] | One Korean semen trial (5 g/day) |
Studied doses
Doses studied in human trials ranged from 1.75 to 5 g/day of maca root powder for 6 to 16 weeks, most often around 3 g/day.[3][5][6]
Interactions
Published interactions only: each row cites a source. No row means none was found in our sources, not that a combination is safe.
None found in our sources.
Who should be careful
- Pregnancy and breastfeeding
- Safety has not been established in trials, so pregnancy and breastfeeding use is unstudied.[2]
Talk to your pharmacist or clinician before starting a supplement, especially if you take prescription medicines.
Safety
Maca is a traditional food, but trials have not measured side effects carefully.
How to read the label
- Label dose vs clinical doseTrials used 1.75–5 g/day of root powder, often 3 g. A 500 mg capsule is a sixth of a 3 g dose.[3][6]
- Gelatinized or rawSeveral trials used gelatinized maca, which is heat-processed to remove starch; one dropout in a raw-powder trial was put down to starch intolerance.[3][4]
- Color typesTrials often named the root color (for example yellow maca); products rarely match a trial exactly.[3][4]
Cost per studied dose, without the sales pitch
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Cost per studied dose
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Frequently asked questions
Does maca increase libido?
The evidence is limited. A review of 4 small trials found some positive results for sexual desire and function, but the reviewers said the trials were too few and too small for firm conclusions.[1]
Does maca improve sperm or fertility?
Not clearly. A 2022 meta-analysis of 5 RCTs found no change in sperm concentration versus placebo, and other semen results were mixed.[3]
Does maca help menopause symptoms?
A review of 4 RCTs found favorable but limited evidence. A crossover trial found lower depression scores and diastolic blood pressure without changes in estradiol or FSH.[2][5]
How much maca was used in studies?
Between 1.75 and 5 g/day of root powder, most often about 3 g/day, for 6 to 16 weeks.[3][5][6]
Sources
- [1]Maca (L. meyenii) for improving sexual function: a systematic review.. BMC Complement Altern Med, 2010. systematic-review
- [2]Maca (Lepidium meyenii) for treatment of menopausal symptoms: A systematic review.. Maturitas, 2011. systematic-review
- [3]Maca (Lepidium meyenii Walp.) on semen quality parameters: A systematic review and meta-analysis.. Front Pharmacol, 2022. meta-analysis
- [4]Evaluation of the effect of Lepidium meyenii Walpers in infertile patients: A randomized, double-blind, placebo-controlled trial.. Phytother Res, 2021. RCT
- [5]Maca reduces blood pressure and depression, in a pilot study in postmenopausal women.. Climacteric, 2015. crossover-RCT
- [6]A double-blind placebo-controlled trial of maca root as treatment for antidepressant-induced sexual dysfunction in women.. Evid Based Complement Alternat Med, 2015. RCT
What changed
- First draft. Every PMID checked against NCBI E-utilities esummary (title and year taken from the record) and abstracts read for the cited rows.
- Adversarial review pass: every row re-read against its abstract and, where open access, the full text (PMC2928177 for the 131-subject total; PMC9468664 for doses and the 244-man total; PMC9293450 for 2.8 g/day). Direction set to mixed or none where results conflicted. Page set indexable.