A child is stunting when it is too small for its age. A children becomes stunting when it hasn’t got enough nutrients for a long time. Especially during the important period of growing up and – more specifically during the first 1000 days following its conception up to the age of two – a reduced growth has adverse effects for the child: reduced mental development, reduced learning ability, poorer school performance and a loss of productivity, resulting in a lower income at a later age. When a child is stunting, it has a higher risk of developing nutrition-related chronic diseases later in life, such as diabetes, high blood pressure and obesity.
Many children in developing countries are exposed to multiple risks for poor development including poverty and poor health and nutrition.
There are few national data for children’s development but our conservative estimate is that more than 200 million children under 5 years of age in developing countries are not developing to their full potential. Sub-Saharan African countries have the highest percentage of disadvantaged children but the largest number live in south Asia. The children will subsequently do poorly in school and are likely to transfer poverty to the next generation.
We estimate that this loss of human potential is associated with more than a 20% deficit in adult income and will have implications for national development. The proximal causes of poor child development are analysed in the second paper in this series.
The problem of poor child development will remain unless a substantial effort is made to mount appropriate integrated programmes. There is increasing evidence that early interventions can help prevent the loss of potential in affected children and improvements can happen rapidly (see third paper in this series). In view of the high cost of poor child development, both economically and in terms of equity and individual well-being, and the availability of effective interventions, we can no longer justify inactivity.