Sarah Maessen and colleagues argue that identifying successful policies and practices in countries with falls in early childhood overweight can help enhance efforts and reduce within country inequities
Nearly every country worldwide has experienced a steady rise in the prevalence of obesity across all age groups in recent decades.1 However, there has been recent optimism about an apparent plateau in prevalence of unhealthy weight among children in some high income countries, particularly among young children.2 A World Health Organization analysis of national surveys from 144 countries described notable increases in the prevalence of overweight and obesity among preschool children (under 5 years) from 1990 to 2010, and predicted an acceleration in prevalence from 2010 to 2020.3 WHO highlighted the preschool years as a potentially critical time in the life course for development of obesity and related metabolic disorders, with most preschool children with overweight or obesity continuing to be above a healthy weight as older children and adults.4 We analyse structural and policy changes in countries that do not seem to be experiencing the predicted rises in prevalence of overweight and obesity among preschool children and urge policy makers to build on this progress and ensure benefit across all societal groups.
Data on trends in overweight and obesity prevalence are scarce for young children and, where available, show considerable heterogeneity between and within countries. We examined national or regionally representative data on trends in early childhood body mass index (BMI) from five countries, four of which were high income (box 1). To support robust temporal and geographical comparisons, we used a threshold of >1 standard deviation above average weight across settings to define overweight, roughly equivalent to the 85th percentile.4 Although more extreme thresholds are used to define obesity in clinical practice, less stringent thresholds …