Recovery from stunting and cognitive outcomes in young children: evidence from the South African Birth to Twenty Cohort Study.

In this study we analyse the implications for cognitive function of recovery from stunting in early childhood. More specifically, we test whether children who met the definition for stunted at age 2, but not at age 5, perform better in cognitive tests than children who remain stunted over this period. The sample is drawn from the Birth to Twenty Cohort Study, a prospective data set of children born in 1990 in urban South Africa. The measure of cognitive function that we use is based on the Revised Denver Prescreening Developmental Questionnaire implemented when the children were age 5. We employ multivariate regression in the analysis to control for child-specific characteristics, socio-economic status, the home environment and caregiver inputs. We find that recovery from stunting is not uncommon among young children in our sample. However, children who recover from stunting by age 5 still perform significantly worse on cognitive tests than children who do not experience early malnutrition, and almost as poorly as children who remain stunted. These findings suggest that the timing of nutritional inputs in the early years is key in a child's cognitive development, with implications for school readiness and achievement.