Prevalence of micronutrient malnutrition worldwide.

Recent estimates indicate that globally over two billion people are at risk for vitamin A, iodine, and/or iron deficiency, in spite of recent efforts in the prevention and control of these deficiencies. The prevalence is especially high in Southeast Asia and sub-Saharan Africa, and pregnant women and young children are at greatest risk. Other micronutrient deficiencies of public health concern include zinc, folate, and the B vitamins. However, there is limited data on the actual prevalence of these deficiencies. Finally, in many settings, more than one micronutrient deficiency exists, suggesting the need for simple approaches that evaluate and address multiple micronutrient malnutrition.