Introduction
Nutrition has always been a key development indicator. Good nutrition allows for healthy growth and development of children, and inadequate nutrition is a major contributing factor to child mortality. Good nutrition is also important for cognitive development and, hence, educational success, both of which are important determinants of labor productivity and hence economic growth. Good nutrition also implies balance – neither undernutrition nor overnutrition.
In what follows we will first briefly review the evolution of nutrition goals, from the Millennium Development Goals (MDGs) to 2015, to the World Health Organization targets to 2025, and the Sustainable Development Goals (SDGs) to 2030. We then comment briefly on the SDG target for nutrition and provide an economic perspective on the goal (using Hoddinott et al., 2013), suggesting that the benefit-cost ratio of nutrition investments is very attractive.
The Evolution of the Nutrition Goals
Stunting – low height for age – is an excellent nutrition indicator to include in the SDGs. It improves on the earlier nutrition indicator used in the MDGs. MDG 1 had two quantitative targets and one qualitative: halving the poverty rate, halving the number “hungry,” and a more aspirational goal regarding access to employment. “Hunger,” in turn, was defined in terms of the number of children who were underweight (using the WHO Child Growth Standards), hence the specific goal was to halve the proportion of children underweight over the period 1990 to 2015.
Over the decade or so since the MDGs were set, our understanding of undernutrition and its measurement has advanced further. Underweight (weight for age) is a composite measure, which aggregates two different aspects of undernutrition, namely weight for height (or wasting, a measure of current nutritional status) and height for age (or stunting, a measure of long-run nutritional status). The underweight goal has served its purpose to focus attention on nutrition. Going forward we can improve on the original MDG target in two ways. First, stunting is a better indicator than underweight. And second, in a world with some regions with growing population, a goal of halving the proportion who are hungry is a weaker goal (easier to achieve) than one of halving the current number who are hungry.