Malnutrition is defined as an imbalance between the body's nutrient needs and intake that can lead to nutritional disorders. It occurs when the body does not get enough vitamins, minerals, and other nutrients needed to maintain healthy tissue and organ function. The main types of malnutrition are undernutrition, overnutrition, and nutritional deficiencies. Malnutrition among children can cause permanent damage to growth and development and is associated with poor school performance. Primary causes include low income, ignorance of nutrition, food scarcity, and overpopulation. Diseases of malnutrition include rickets, goiter, kwashiorkor, anemia, and growth retardation. Prevention focuses on eating a balanced diet with regular meals and snacks and drinking fluids after rather than during meals.