A narrative literature review of the development of obesity in infancy and childhood.

This narrative review explains the development of excess weight gain in babies and children. It takes a life course approach which includes genetics, pre-conception, pregnancy, infancy and childhood. The paper focuses on feeding behaviours, physical activity, parental influences and the wider social and environmental context. Risk factors which can cumulatively lead to excess childhood weight gain include: under- or overweight during pregnancy; the presence of diabetes during pregnancy; low or high birth weight; having obese parents; early weaning; prolonged formula feeding; rapid weight gain in the first year; disinhibited eating patterns and the consistent availability of energy dense food at home; feeding practices which are not responsive to the child's cues; insufficient sleep among preschool children; sedentary parents; low parental education; living in poor socio-economic circumstances; absence, or perceived absence, of safe play areas; parents who lack time or confidence to authoritatively parent; environments where there is poor access to affordable lower energy dense foods; and parents who do not accept that excess weight is a health problem. Recommendations for health professionals are made.