Table 1.
Summary of randomised clinical trials with maca for sexual function
| First author (year) location | Sample size/condition Age (years) Sex (M/F) Duration of disease | Intervention (regimen) | Control intervention (regimen) | Main outcome measures | Results | Adverse effects |
|---|---|---|---|---|---|---|
| Zenico (2009) [21] Italy | 50 mild ED 36 (SDs, 5) (50/0) n.r. |
(A) Maca (pulverised dehydrated maca roots directly imported from Peruvian Andes, tablets, 2400 mg/d, 1200 mg/d, 2 daily for 12 weeks, n = 25), no follow-up | (B) Placebo tablets (2400 mg/d, 1200 mg/d, 2 daily for 12 weeks, n = 25) | IIEF-5 | Intergroup: MD, 1.10 [0.61, 1.59], P < 0.001 |
n.r. |
| Within group: (A) P < 0.05, (B) P < 0.05 |
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| Brooks (2003) [22] Australia | 16 healthy postmenopausal women with moderate severity of menopausal symptoms | (A) Maca (company commercial product, dried maca powder, 3500 mg/d, daily for 6 weeks, n = 14), 6 weeks follow-up | (B) Placebo (refined white rice flour, 3500 mg/d, daily for 6 weeks, n = 14) | Sexual dysfunction (GCS) | Intergroup: MD, 0.70 [0.08, 1.32], P < 0.05 |
n.r. |
| 54 (SDs, 11) (0/16) >12 months amenorrhea |
Within group: (A) P < 0.05, (B) NS |
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| Gonzales (2002) [23] Peru | 57 adult healthy men 21-56 (57/0) N/A |
(A) Maca (company commercial product, gelatinised maca, 1500 mg/d; 500 mg/d, 3 tablets, daily for 12 weeks, n = 30), no follow-up | (C) Placebo tablets (n.r., daily for 12 weeks, n = 12) | Self-perception on sexual desire | Intergroup: MD, 0.51 [-0.35, 1.37], NS at 4 weeks; MD, 1.64 [1.07, 2.21], P < 0.008 at 8 weeks; MD, 1.64 [1.07, 2.21], P < 0.006 at 12 weeks |
n.r. |
| (B) Maca (company commercial product, gelatinised maca, 3000 mg/d; 500 mg/d, 6 tablets, daily for 12 weeks, n = 15), no follow-up | Within group: (A) P < 0.05 at 4, 8, and 12 weeks, (B) NS at 4, 8, and 12 weeks |
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| Stone (2009) [24] UK | 8 experienced and endurance trained male (cyclists) | (A) Maca (company commercial product, gelatinised maca, 2000 mg/d for 2 weeks, n = 8), no follow-up | (B) Placebo capsules (Arabic gum, n = 8) | Sexual Desire Inventory | Intergroup: MD, 6.38 [-11.32, 24.08], NS |
n.r. |
| 30 (SDs, 7) 8/0 N/A Cross-over (1 week washout period) |
Within group: (A) P = 0.01, (B) P = 0.90 |
ED: erectile dysfunction; GCS: Greene Climacteric Scale; IIEF-5: International Index of Erectile Dysfunction; NS: not significant; n.r.: not reported; SDs: standard deviations