Overweight and obesity at school entry among migrant and German children: a cross-sectional study

Background: Overweight and obesity have become a global epidemic and are increasing rapidly in both childhood and adolescence. Obesity is linked both to socioeconomic status and to ethnicity among adults. It is unclear whether similar associations exist in childhood. The aim of the present study was to assess differences in overweight and obesity in migrant and German children at school entry. Methods: The body mass index (BMI) was calculated for 525 children attending the 2002 compulsory pre-school medical examinations in 12 schools in Bielefeld, Germany. We applied international BMI cut off points for overweight and obesity by sex and age. The migration status of children was based on sociodemographic data obtained from parents who were interviewed separately. Results: The overall prevalence of overweight in children aged 6-7 was 11.9% (overweight incl. obesity), the obesity prevalence was 2.5%. The prevalence of overweight and obesity was higher for migrant children (14.7% and 3.1%) than for German children (9.1% and 1.9%). When stratified by parental social status, migrant children had a significantly higher prevalence of overweight than German children in the highest social class. (27.6% vs. 10.0%, p = 0.032) Regression models including country/region and socioeconomic status as independent variables indicated similar results. The patterns of overweight among migrant children differed only slightly depending on duration of stay of their family in Germany. Conclusion: Our data indicate that children from ethnic minorities in Germany are more frequently overweight or obese than German children. Social class as well as family duration of stay after immigration influence the pattern of overweight and obesity in children at school entry.