PhD defence Junwen Yang

The main aim of this thesis was to study social inequalities in children’s lifestyle behaviors and child overweight, asthma, and health-related quality of life (HRQoL). The studies conducted in this thesis were embedded in the Generation R Study. The following conclusions can be drawn from the studies presented in this thesis. Social inequalities in the clustering of children’s lifestyle behaviors (screen time, physical activity, calorie-rich snack, and sugar-sweetened beverages) are present among school-aged children. From preschool to school-age the trajectories of children’s television time may vary according to indicators of social status. Findings also indicate that social inequalities in childhood asthma and indicators of lung function are present among school-aged children. Experiencing family poverty, either as an intermittent episode or as a chronic situation, is associated with childhood overweight, asthma, and HRQoL. When parents obtain a higher level of education after their child is born, this might be beneficial to attenuate the risk of the child developing overweight at school age. A joint effort between parents, schools, community, public health professionals, and policymakers is needed to reduce these inequalities.