Background. The nutritional status of school-aged children impacts their health, cognition, and subsequently their educational achievement. The school is an opportune setting to provide health and nutrition services to disadvantaged children. Yet, school-aged children are not commonly included in health and nutrition surveys. An up-to-date overview of their nutritional status across the world is not available.

Objective. To provide a summary of the recent data on the nutritional status of school-aged children in developing countries and countries in transition and identify issues of public health concern.

Methods. A review of literature published from 2002 to 2009 on the nutritional status of children aged 6 to 12 years from Latin America, Africa, Asia, and the Eastern Mediterranean region was performed. Eligible studies determined the prevalence of micronutrient deficiencies or child under- and overnutrition using biochemical markers and internationally accepted growth references.

Results. A total of 369 studies from 76 different countries were included. The available data indicate that the nutritional status of school-aged children in the reviewed regions is considerably inadequate. Underweight and thinness were most prominent in populations from South-East Asia and Africa, whereas in Latin America the prevalence of underweight or thinness was generally below 10%. More than half of the studies on anemia reported moderate (> 20%) or severe (> 40%) prevalence of anemia. Prevalences of 20% to 30% were commonly reported for deficiencies of iron, iodine, zinc, and vitamin A. The prevalence of overweight was highest in Latin American countries (20% to 35%). In Africa, Asia, and the Eastern Mediterranean, the prevalence of overweight was generally below 15%.

Conclusions. The available data indicate that malnutrition is a public health issue in school-aged children in developing countries and countries in transition. However, the available data, especially data on micronutrient status, are limited. These findings emphasize the need for nutrition interventions in school-aged children and more high-quality research to assess nutritional status in this age group.