Zinc Oxide is an inorganic compound. It occurs naturally as the mineral zincite, but most zinc oxide is produced synthetically. It is added to many food products and used as a supplementary source of zinc, as it plays an important role in cell growth and division, energy production, immune function, DNA and protein synthesis, cognitive function, fertility and reproduction, the maintenance of normal testosterone levels, bones, hair, nails and vision, and vitamin A metabolism. It also contributes to growth and tissue repair, and the protection of cells from oxidative stress.