Globally, underweight prevalence in children under 5 years old declined from 31 per cent to 26 per cent between 1990 and 2008; the rate of reduction is insufficient for achievement of the MDG target. Efforts to adequately target children who are underweight need to be rapidly scaled up if the target is to be met with equity.

Only half of all countries (62 of 118) are on track to achieve the MDG target, the majority of them middle-income countries. Most countries making insufficient or no progress are in sub-Saharan Africa or South Asia.

There is little difference in underweight prevalence between girls and boys. Yet in all regions of the world, children living in rural areas are more likely to be underweight than children in urban areas. In developing countries, children are twice as likely to be underweight in rural areas as in urban areas. With regard to wealth, children from the poorest 20 per cent of households are more likely to be underweight than those from the richest 20 per cent.

Progress in reducing underweight prevalence is often unequal between the rich and the poor. In India, for example, there was no meaningful improvement among children in the poorest households, while underweight prevalence in the richest 20 per cent of households decreased by about a third between 1990 and 2008.

Undernutrition is the result of a combination of factors: lack of food in terms of quantity and quality; inadequate water, sanitation and health services; and suboptimal care and feeding practices. Until improvements are made in these three aspects of nutrition, progress will be limited.