Zinc is an essential element whose significance to health is increasingly appreciated. In 1961 essentiality of zinc for humans was recognized. A systematic literature search was done to identify relevant studies investigating the role of zinc in human health. This review concerns the importance of zinc in health and the consequences of its deficiency. Zinc deficiency leads to complications of pregnancy and childbirth, low birth weight and poor growth in childhood, reduced immunocompetence, and increased infectious disease morbidity. Pregnant women with zinc deficiency are at risk of premature labour and miscarriages, inefficient labour and delivery, stillbirths, lower mental ability of the child, retarded foetal growth and low immunity of both mother and baby. Zinc can reduce the duration, severity and incidence of diarrhea in children. Zinc deficiency was indicated as a risk factor for immune deficiency and susceptibility to infection in the elderly. Zinc is used in preventive trials and treatment of diarrhea, pneumonia, common cold, respiratory infections and malaria. Sufficient zinc is essential in maintaining immune system function. Supplementation of zinc and with other micronutrients may be beneficial during periods of greatest vulnerability such as early childhood, pregnancy and elderly. Ensuring adequate levels of zinc intake should be a key component in efforts to reduce illness.
Zinc, Deficiency, Human health