By goal
Evidence-Backed Supplements for Testosterone and Male Libido
Plenty of supplements are marketed as testosterone boosters, but the evidence behind them varies widely, from a handful of decent randomized trials to little more than tradition. Here we grade what each substance actually does for testosterone, libido, and erectile function, including popular options that don't hold up. Correcting a genuine deficiency (zinc, vitamin D, magnesium) tends to matter far more than any booster, and low libido can have medical causes worth discussing with a clinician.
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Best-supported here: Creatine Monohydrate (Strong), Vitamin D3 (Strong), L-Citrulline (Moderate), Magnesium (Moderate) — each graded below by the weight of human evidence.
| Supplement | Evidence for this goal | Typical dose | Key caution | Studies |
|---|---|---|---|---|
| Creatine Monohydrate | Strong | 3–5 g/day. Optional loading: 20 g/day (split) for 5–7 days. | Very safe. | 19 |
| Vitamin D3 | Strong | 1,000–2,000 IU/day maintenance; higher to correct deficiency under test… | Tolerable upper limit ~4,000 IU/day for most adults; toxicity (hypercalcemia) occurs with c… | 16 |
| L-Citrulline | Moderate | 6–8 g citrulline malate (or ~3–4 g pure L-citrulline) ~60 min pre-exerc… | Very safe, well tolerated. | 22 |
| Magnesium | Moderate | 200–400 mg elemental/day. Glycinate & citrate absorb best; oxide is poo… | Safe. | 20 |
| Saffron | Moderate | 30 mg/day standardized extract. | Safe at supplement doses. | 20 |
| Tongkat Ali | Moderate for this goal | 200–400 mg/day standardized extract. | Limited long-term data. | 15 |
| Zinc | Moderate | 8–11 mg/day RDA; up to 40 mg upper limit. Lozenges (75mg+/day) only sho… | Safe within limits (adult upper limit ~40 mg/day). | 21 |
| Ashwagandha | Preliminary for this goal | 300–600 mg/day of root extract (standardized to 5% withanolides), often… | Avoid in pregnancy (traditionally abortifacient) and while breastfeeding. | 18 |
| Horny Goat Weed | Preliminary | Extracts standardized to icariin; an effective human dose is not establ… | Generally well tolerated short-term, but documented case reports include tachyarrhythmia, a… | 18 |
| Maca | Preliminary for this goal | 1.5–3 g/day of dried root powder (as used in trials). | Generally well tolerated as a food. | 15 |
| Panax Ginseng | Preliminary | 200–400 mg/day standardized extract. | Generally safe short-term. | 16 |
| Saw Palmetto | Preliminary for this goal | 320 mg/day of a lipophilic berry extract standardized to 85-95% fatty a… | Generally well tolerated; in trials adverse events (mild GI upset, headache, occasional dec… | 13 |
| Shilajit | Preliminary for this goal | 250–500 mg/day of a PURIFIED, lab-tested extract. Never use raw shilaji… | ⚠ Unpurified shilajit can contain dangerous heavy metals (lead, arsenic). | 16 |
| Tribulus Terrestris | Mixed | Commonly 250–750 mg/day standardized extract; benefit for testosterone… | Usually well tolerated, but rare, serious liver and kidney injury (including a fatal acute-… | 16 |
| Yohimbe / Yohimbine | Mixed | Highly variable and often mislabeled in supplements; prescription yohim… | ⚠ Raises blood pressure and heart rate; linked to arrhythmia, heart attack, seizures and an… | 16 |