Overweight and obesity in 6-12 year old children in Switzerland.

OBJECTIVES: Our aim was to estimate the national prevalence of overweight and obesity in Swiss primary schoolchildren and to determine if adiposity is increasing in this age group. METHODS: We used a cross-sectional, 3-stage, probability-proportionate-to-size cluster sampling of primary schools throughout Switzerland to obtain a representative national sample of 6-12 year old children (n = 2431). Height and weight were measured and used to calculate body mass index (BMI). BMI references from the U.S. Centers for Disease Control and Prevention (CDC) and the International Obesity Task Force (IOTF) were used to define adiposity. The triceps, biceps, subscapular and suprailiac skinfold thickness (SFT) was measured and used to calculate body fat percentage (BF%). BMI and BF% were compared to data from 6-12 year old Swiss children in the 1960's and 1980's. RESULTS: BMI and BF% were well correlated in both boys and girls (r2 = 0.74). Using the IOTF references, the prevalence of overweight and obesity was 16.6% and 3.8% in boys and 19.1% and 3.7% in girls. Using the CDC references, the prevalence of overweight and obesity was 19.9% and 7.4% in boys and 18.9% and 5.7% in girls. There was no significant age or gender difference in the prevalence of overweight or obesity. At all ages, boys and girls had 50-100% higher mean BF% than Swiss children from the 1960's and 1980's. Using the current CDC BMI references, the prevalence of overweight has increased more than 5-fold in Swiss children since the mid-1980's. CONCLUSIONS: These findings suggest there has been a striking increase in BF% and the prevalence of overweight and obesity in Swiss children in the last two decades.