Physiological and medicinal zinc

Functions of zinc Zinc is critical for the function of about 60 enzymes in humans. It is a co-factor in a range of biochemical processes, including the synthesis of deoxyribonucleic acid, ribonucleic acid and proteins. Zinc is required for the hepatic synthesis of retinol binding protein, the protein involved in transporting vitamin A.Without adequate zinc, symptoms of vitamin A deficiency can appear even if vitamin A supplements are taken. Zinc also acts as an antioxidant, restricting endogenous free radical production and acting as a structural component of the extracellular antioxidant enzyme, superoxide dismutase. It also helps to protect against depletion of vitamin E and maintains tissue concentrations of metallothionein, a possible scavenger of free radicals. Other biochemical processes that require zinc include carbohydrate metabolism, protein digestion, blood clotting and bone metabolism.