Serum testosterone compared with serum zinc in man.

Serum zinc was measured in 154 male and 95 female blood donors. Men had higher serum zinc levels than women, the difference being statistically significant (p less than 0.001). The correlations between serum zinc and serum testosterone, serum zinc and serum FSH and serum zinc and serum LH were studied in 40 men aged 28-60 years and a statistically significant positive correlation was found only between serum zinc and serum testosterone in men of age 36-60 years (p less than 0.005). These results do not support the theory that slight zinc deficiency primarily effects pituitary gonadotropins but indicate that it would rather act on testicular level.