Trends in obesity prevalence and changes in adiposity across ethnic groups: findings from a population-based prospective cohort study in Amsterdam, the Netherlands (HELIUS study)

Background and aim: Obesity has reached epidemic proportions worldwide, with large differences across regions. European data on obesity trends among ethnic groups is scarce, particularly regarding the influence of age and socioeconomic status on these trends, which is crucial for guiding targeted interventions. In this study, we assessed the prevalence of obesity and changes in body mass index (BMI) and waist circumference (WC) over time and the effects of key sociodemographic factors on these changes using longitudinal data from a large multi-ethnic cohort. Methods: Using baseline and follow-up data from 10 484 participants in the HEalthy Life in an Urban Setting (HELIUS) study, representing Dutch, South-Asian Surinamese, African Surinamese, Ghanaian, Moroccan and Turkish populations; age-adjusted obesity prevalence; BMI and WC changes over an average follow-up of 6.3 (SD 1.2) years were calculated. Linear mixed models were used to assess changes in BMI and WC over time, adjusting for age, sex and socio-economic position. Key analyses were stratified by age (younger