Effects of Zinc Supplementation on Testosterone Levels and Immune Function
Prasad AS, et al.
Evidence is still building up
Summary
An RCT examining the effects of zinc supplementation (45 mg/day, 6 months) on testosterone and immune function in zinc-deficient young and older men. Testosterone was significantly lower in zinc-deficient individuals and recovered to normal range with supplementation. Immune markers (NK cell activity, IL-2, etc.) also improved.
Key findings
- 1
In zinc-deficient older men, testosterone approximately doubled with supplementation (recovery within normal range)
- 2
Immune function markers—NK cell activity, T-cell proliferation, and IL-2 production—improved significantly
- 3
No testosterone increase was observed in men with normal zinc status from additional supplementation
- 4
Small sample size (n=40) limits generalizability
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