Chronic disease and infant nutrition: is it significant to public health?

OBJECTIVE To assess the public health significance of premature weaning of infants from breast milk on later-life risk of chronic illness. DESIGN A review and summary of recent meta-analyses of studies linking premature weaning from breast milk with later-life chronic disease risk is presented followed by an estimation of the approximate exposure in a developed Western country, based on historical breast-feeding prevalence data for Australia since 1927. The population-attributable proportion of chronic disease associated with current patterns of artificial feeding in infancy is estimated. RESULTS After adjustment for major confounding variables, current research suggests that the risks of chronic disease are 30-200 % higher in those who were not breast-fed compared to those who were breast-fed in infancy. Exposure to premature weaning ranges from 20 % to 90 % in post-World War II age cohorts. Overall, the attributable proportion of chronic disease in the population is estimated at 6-24 % for a 30 % exposure to premature weaning. CONCLUSIONS Breast-feeding is of public health significance in preventing chronic disease. There is a small but consistent effect of premature weaning from breast milk in increasing later-life chronic disease risk. Risk exposure in the Australian population is substantial. Approximately 90 % of current 35-45-year-olds were weaned from breast-feeding by 6 months of age. Encouraging greater duration and exclusivity of breast-feeding is a potential avenue for reducing future chronic disease burden and health system costs.