28. Stunting, Wasting, and Micronutrient Deficiency Disorders

Abstract

Undernutrition and micronutrient deficiencies contribute significantly to the global burden of disease by means of an insidious synergy. Undernutrition reduces immunological defenses against disease, and disease deprives the body of essential nutrients. In the long term, undernutrition and micronutrient deficiencies result in lost wages, increased health care costs, and impaired intellectual development, all exacerbating a cycle of poverty.

Eliminating malnutrition could not only prevent more than half of the deaths of young children, primarily in South Asia and Sub–Saharan Africa, but it could also reduce the risk and cost of chronic diseases. Vitamin A and iron deficiencies decrease immune function; iodine deficiency can result in impaired intellectual development and physical growth; and zinc deficiency affects all three functions. Interventions include promotion of optimal feeding of infants and young children, such as early exclusive breastfeeding; water, sanitation, and hygiene interventions; and vitamin intake through supplementation or fortified foods.

Few health interventions are as cost–effective as programs that promote appropriate feeding and correct micronutrient deficiencies, with iodine supplementation or fortification being the most widespread and successful. Nutritional interventions not only preserve or improve cognitive function, but also contribute to improved adult stature and worker productivity. In addition, reducing malnutrition frees scarce health resources to be allocated to other health crises. While progress has been made in correcting vitamin A deficiency and promoting breastfeeding, important challenges remain in combating iron and zinc deficiencies.