International differences in gradients in early childhood overweight and obesity: the role of maternal employment and formal childcare attendance.

BACKGROUND: There are significant cross-country differences in socio-economic gradients in later childhood and adulthood overweight/obesity; few studies assess whether this cross-national variation is evident from early childhood. Furthermore, the role of childcare in explaining overweight/obesity gradients might vary across countries, given differences in access, quality and heterogeneity within. Additionally, childcare is linked to parental characteristics such as maternal employment. The interplay between childcare and employment in producing early overweight/obesity gradients has received little attention, and might vary cross-nationally. METHODS: Using harmonized data from six high-quality, large datasets, we explore the variation in gradients in early overweight/obesity (at age 3-4 years old) by parental education across several high-income countries (USA, UK, France, the Netherlands, Germany and Japan). We then assess whether differential formal group care use attenuates some of these gradients, and whether this varies across maternal employment. RESULTS: Gradients in early childhood overweight/obesity by parental education are evident across several developed countries. Countries with higher overall prevalence of early overweight/obesity did not have the largest inequalities across education groups. The contribution of formal group care to producing these gradients varied across countries and across maternal employment status. CONCLUSION: Early childhood inequalities in overweight/obesity are pervasive across developed countries, as noted for older children and adults. However, mechanisms producing these gradients vary across national contexts. Our study shows that, given the right context, quality childcare and maternal employment can successfully support healthy weight trajectories and not contribute (or even reduce) social inequalities in early overweight/obesity.

The role of energy balance related behaviors in socioeconomic inequalities in childhood body mass index: A comparative analysis of Germany, the Netherlands, the United Kingdom, and the United States.

Socioeconomic inequalities in childhood Body Mass Index (BMI) are becoming increasingly more pronounced across the world. Although countries differ in the direction and strength of these inequalities, cross-national comparative research on this topic is rare. This paper draws on harmonized longitudinal cohort data from four wealthy countries-Germany, the Netherlands, the United Kingdom (UK), and the United States (US)-to 1) map cross-country differences in the magnitude of socioeconomic inequalities in childhood BMI, and 2) to examine cross-country differences in the role of three energy-balance-related behaviors-physical activity, screen time, and breakfast consumption-in explaining these inequalities. Children were aged 5-7 at our first timepoint and were followed up at age 8-11. We used data from the German National Educational Panel Study, the Dutch Generation R study, the UK Millennium Cohort Study and the US Early Childhood Longitudinal-Kindergarten Study. All countries revealed significant inequalities in childhood BMI. The US stood out in having the largest inequalities. Overall, inequalities between children with low versus medium educated parents were smaller than those between children with high versus medium educated parents. The role of energy-balance-related behaviors in explaining inequalities in BMI was surprisingly consistent. Across countries, physical activity did not, while screen time and breakfast consumption did play a role. The only exception was that breakfast consumption did not play a role in the US. Cross-country differences emerged in the relative contribution of each behavior in explaining inequalities in BMI: Breakfast consumption was most important in the UK, screen time explained most in Germany and the US, and breakfast consumption and screen time were equally important in the Netherlands. Our findings suggest that what constitutes the most effective policy intervention differs across countries and that these should target both children from medium as well as low educated families.