Zinc is an essential mineral that is naturally present in some foods. Zinc is involved in numerous aspects of the cellular metabolism. It is required for the catalytic activity of approximately 100 enzymes and it plays a role in immune function, protein synthesis, wound healing, DNA synthesis, and cell division. Zinc also supports normal growth and development during pregnancy, childhood, and adolescence and is required for proper sense of taste and smell. In addition, it also helps to normal cognitive functioning, vision and fertility. A daily intake of zinc is required to maintain a steady state because the body has no specialized zinc storage system.
Zinc is involved in the regulation and maintenance of the normal activity of special immune cells. Some studies have demonstrated a relationship between zinc intake and reduction in the length and severity of a cold.
Because of its immune regulating mechanism, zinc is also critical in wound healing and the various stages of tissue reconstruction. When the skin is ruptured, the inflammatory process is activated and special immune cells are directed to the wound. There they remove bacteria from the wound. Wound healing also consists of growth of new tissue, and zinc is thought to have a beneficial role in new cell formation.
Zinc also has a role in normal bone maintenance. Zinc is contained in crystals that form a bone matrix and is required to stimulate bone formation and inhibit bone decomposition. It is probable that zinc, in combination with calcium, might protect against the risk for osteoporosis.
Researchers have suggested that both zinc and antioxidants delay the progression of age-related macular degeneration and vision loss, possibly by preventing cellular damage in the retina.The European Food Safety Authority (EFSA) has acknowledged the following beneficial effects as a basis for health claims:
• Zinc contributes to normal function of the immune system
• Zinc contributes to normal DNA synthesis and cell division
• Zinc contributes to the protection of cell constituents from oxidative damage
• Zinc contributes to maintenance of normal bone
• Zinc contributes to normal cognitive function
• Zinc contributes to normal fertility and reproduction
• Zinc contributes to normal metabolism of fatty acids
• Zinc contributes to normal acid-base metabolism
• Zinc contributes to normal metabolism of vitamin A
• Zinc contributes to maintenance of normal vision