Human milk is the optimal feeding choice for infants, as it dynamically provides the nutrients, immunity support, and other bioactive factors needed for infants at specific stages during development. Observational studies and several meta-analyses have suggested that breastfeeding is protective against development of obesity in childhood and beyond. However, these findings are not without significant controversy. This review includes an overview of observational findings to date, then focuses on three specific pathways that connect human milk and infant physiology: maternal obesity, microbiome development in the infant, and the development of taste preference and diet quality. Each of these pathways involves complex interactions between mother and infant, includes both biologic and non-biologic factors, and may have both direct and indirect effects on obesity risk in the offspring. This type of integrated approach to examining breastfeeding and childhood obesity is necessary to advance research in this area beyond observational findings.
Keywords: Bioactive; Childhood obesity; Confounding; Epidemiology; Human milk.