Fertility Decoded

Selenium

Written by Fertility Decoded. Reviewed by D R, MS (OBG), FRM. Review date: 31 August 2026.

The verdict

Essential for sperm production; supplementation trials mixed, one combo study showed some markers worsening.

A trace element required for testosterone biosynthesis and spermatogenesis; sold standalone and combined with vitamin E in many products.

What the evidence shows

Mechanistically essential; supplementation-trial evidence mixed. One combined selenium + vitamin E meta-analysis found reduced semen volume and total sperm count, alongside improved vitality and normal morphology — a genuinely mixed result.

Evidence tier

Non-Cochrane evidence

🟡 Smaller systematic reviews/meta-analyses or RCTs exist, no Cochrane-grade synthesis. Emerging, not proven.

Frequently asked questions

Does selenium help male fertility?
It's mechanistically essential for sperm production, but supplementation trials are mixed — one selenium+vitamin E study even showed reduced semen volume and sperm count alongside some improved markers.
Selenium for sperm — worth taking?
Evidence is genuinely mixed; treat marketing claims cautiously and discuss with a doctor.

Sources

Take this further

Sources last reviewed .