The zinc-immunodeficiency relationship in old patients.

The influence of oral zinc sulphate therapy on the humoral immunity was investigated by dosages of serum immunoglobulins (Ig) and of plasma zinc levels in 12 patients with a mean age of 70 years, in comparison with other 11 patients treated with placebo and with a control group of 50 apparently healthy subjects. The results of this double-blind study demonstrated the zinc effect on the immunoregulation, as the Ig levels, and particularly those of the IgG class, initially high, were lowered in a statistically significant proportion. It is assumed that further clinical trials with various zinc concentrations could bring more information on this trace element participation in the humoral immunoregulation.