Objective: This study shows zinc functions on growth, dietary intake and nutritional state of children and adolescents, based on scientific literature. Methodology: A research on data bases (Medline, Lilacs and Scielo) was done, with keywords related to the subject. Results: Zinc carries out crucial functions in infancy. Zinc deficiency is a common problem in developing countries, with serious consequences: retarded growth, impairment of cognitive and immune function. During adolescence, it may affect growth, bone mineralization and sexual maturation. Zinc deficiency is associated with anorexia and decreased taste acuity and sense of smell. This problem among obese people suggests the participation of zinc in this pathology, through the reduction of the basal metabolic rate, as a consequence of an impaired thyroid hormone action, that needs this nutrient. Conclusion: Considering the unhealthy eating habits observed among children and adolescents, it is essential to take actions in order to eliminate zinc deficiency.