Zinc and infection in the elderly:
Seniors and zinc benefits: Prasad AS et al found that healthy seniors who supplement with zinc experience a reduced rate of infections and oxidative stress. In the current randomized, double-blind, placebo-controlled trial, researchers determined whether zinc would have an effect on the incidence of total infections in 50 subjects aged 55 to 87 years. They also investigated if zinc would have an effect on oxidative stress markers, and on the generation of tumor necrosis factor, a group of white blood cells known as cytokines responsible for inflammation that are linked to everything from psoriasis to heart failure. Researchers gave the zinc-supplemented group 45 mg zinc gluconate orally on a daily basis for 12 months. Researchers documented the incidence of infections during the supplementation period as well as the generation of inflammatory cytokines, T helper 1 and T helper 2 cytokines, and oxidative stress markers. The plasma concentrations of zinc were measured at baseline and after supplementation. Compared with a group of younger adults, at baseline, the older subjects had significantly lower plasma zinc, higher generation of inflammatory cytokines and interleukin 10, and higher plasma oxidative stress markers and endothelial cell adhesion molecules. Endothelial cells are the cells lining the arteries and the increase in adhesion molecules signifies that increased build up and inflammation was occurring in the arteries of the subjects. In subjects supplemented with zinc, the incidence of infections declined. In addition, the generation of tumor necrosis factor and plasma oxidative stress markers were significantly lower in zinc-supplemented subjects compared to the placebo group. (6)