Dietary risk factors for development of childhood obesity

Controversial information exists on the contribution of several dietary factors for overweight development in childhood, but there is no doubt that obesity prevalence is increasing. We review the most up-to-date information in order to clarify the evidence-based dietary aspects influencing obesity development in children and adolescents.

Longitudinal studies are the preferred method for analysing the relationship between dietary factors and obesity development. With the exception of infants, there are no conclusive associations between energy intake or diet composition and later overweight development in children. Among formula or mixed-fed infants, the increase in energy intake has been associated with an increased risk of being overweight during childhood. Breastfeeding seems to be a protective factor for later obesity development. In terms of food intake, longitudinal studies have only found a clear and positive association between obesity development and sugar-sweetened beverage consumption; this is not the case with snacking, fast food or food portion sizes. Cross-sectional studies have found correlations between being overweight in childhood and buying lunch at school, eating supper while watching television or without family supervision, consuming less energy at breakfast or more at dinner, and missing breakfast.

Results from longitudinal studies must be taken into account in order to design preventive strategies to counteract the increased prevalence of obesity and its consequences in children. Lack of breastfeeding, high early energy intake and high intake of sugar-sweetened beverages seem to be the main dietary factors contributing to obesity development.