Mineral Zinc is an essential mineral that plays a major role in growth, reproduction, antioxidant defenses, and healthy immune function. Zinc is a critical nutrient for the immune system. The normal, healthy development of immune cells, particularly T-lymphocytes depends upon adequate zinc status. Zinc deficiency has been shown to reduce the physical size of the thymus gland; it is here where T cells mature to become fully functional mature T-lymphocytes. These cells are critical for a healthy immune response. Provided as a lozenge, zinc gluconate has been shown to reduce the severity and duration of the common cold, as well as reduce antibiotic use in school-age children with a cold.