Zinc and immunoresistance to infection in aging: new biological tools.

Infections can cause mortality when the immune system is damaged. The catalytic, structural (in zinc-finger proteins) and regulatory roles of zinc mean that this ion is involved in the maintenance of an effective immune response. Both zinc deficiency and impaired cell-mediated immunity combine during aging to result in increased susceptibility to infection. Dietary supplementation with the recommended daily allowance of zinc for between one and two months decreases the incidence of infection and increases the survival rate following infection in the elderly. This article reviews the biochemical pathways through which zinc might act to increase immunoresistance to infection in the elderly.