Malnutrition, including micronutrient deficiencies, is the leading risk factor for child mortality in low-income and middle-income countries. About 30% of the worldÊ¼s population has zinc deficiency (). This deficiency occurs because zinc is mainly contained in foods such as red meat that are expensive and in short supply in developing countries. Moreover, zinc has no tissue reserves, unlike vitamin A and iron, and its turnover is rapid, especially during common gastrointestinal infections. Young children in developing countries who have a poor diet and high exposure to gastrointestinal pathogens are at greatest risk of zinc deficiency.