Nutritional zinc deficiency is increasingly recognized as a global public health concern. Zinc plays a critical role in human health and development. Insufficient zinc in the daily diet contributes to stunted growth of children, depressed immunity, increased rates of infections such as diarrhea and pneumonia and possibly increased mortality rates resulting from those infections. Zinc deficiency also can cause problems during pregnancy and abnormal neuro-behavioral development. "Data indicate that as much as one-half of the world's population is at risk of zinc deficiency and 40 percent of children in low-income countries have stunted growth related to zinc deficiency," says Kenneth H. Brown, a UC Davis nutrition professor. "Infants, young children and pregnant or nursing women are especially at high risk for zinc deficiency because they have increased needs for this essential nutrient." To address the problem of zinc deficiency, the International Zinc Nutrition Consultative Group was recently established by the Nutrition Programme of the United Nations University and the International Union of Nutrition Scientists. The group is based at UC Davis under Brown's direction and is co-chaired by Juan Rivera of the National Institute of Public Health in Mexico. The group's steering committee is currently preparing guidelines for assessing zinc status in different populations and alternative methods for controlling zinc deficiency.