Of the 555 million preschool children in developing countries, 32 per cent are stunted and 20 per cent are underweight. Child underweight or stunting causes about 20 per cent of all mortality of children under 5 years of age and leads to long-term cognitive deficits, poorer performance in school, and fewer years of completed schooling, and lower economic productivity in adulthood.
Child underweight state or stunting mainly develops during the first 2 years of life, when mean weight-for-age and length-for-age Z scores of children in Africa and Asia drop to about −2·0, with little or no recovery thereafter.
