Association of breastfeeding and stunting in Peruvian toddlers: an example of reverse causality.

ABSTRACT

PIP: There has been a perplexing finding, in many developing countries, of increased rates of stunting and growth faltering in breast-fed toddlers receiving complementary foods relative to their non-breast-fed counterparts. Longitudinal data on 134 children 12-15 months of age from Lima, Peru, were used to investigate the hypothesis that the negative association between growth and breast feeding reflects reverse causality. The toddlers were participants in a broader persistent diarrhea surveillance survey conducted during 1985-87. 72.9% of children were breast-fed beyond 12 months (median duration, 16.8 months). Anthropometric measurements revealed stunting in 19.4% of toddlers at 12 months and in 29.1% at 15 months. Linear growth between 12 and 15 months had a complex relationship with breast feeding, diarrhea, and dietary factors. Increased breast feeding was associated with a 1.0 cm decrease in length gain between 12 and 15 months when dietary intake was low and diarrheal morbidity was high. However, logistic analysis demonstrated that mothers whose children had low dietary intakes, low weight-for-age, and increased incidence of diarrhea were less likely to wean their infants at 12 and 14 months. This finding that mothers modified their children's feeding practices according to the child's health and growth status supports a reverse causality process in which poor growth is a determinant rather than a result of breast feeding.