Undernutrition, also known as malnutrition, is the largest contributor to child mortality worldwide according to the World Health Organization. Chronic undernutrition can impair cognitive development in children by negatively impacting brain development. Stunting, low height and weight for age, can result from undernutrition. Undernutrition also increases the risk of death from infectious diseases in children. Effective interventions to address undernutrition include promoting breastfeeding, complementary feeding, micronutrient supplementation, improving family nutrition, and reducing disease burden.