Incidencia del periodo vacacional de navidad en el estado ponderal de escolares de primaria

Introduction: The aim of this study was to analyze changes in body mass index (BMI) of primary-school students and the differences between children with normal-weight, overweight and obesity after the Christmas holiday period. Material and Methods: Longitudinal and prospective descriptive study was performed. A total of 156 students of the public school Doctor Fleming from Jodar, Jaen (Spain) participated in this study, aged 8 to 12 years: 119 with normal-weight, 18 with overweight and 19 with obesity. Measurements of height, weight, and BMI were taken at three moments: in the school period prior to the Christmas holiday, after a non-school period (Christmas holiday) and 20 days after the Christmas holiday, with an interval time between measurements of 20 days. Results: The data (mean [standard deviation]) showed an increase in the BMI after the Christmas holiday period in all groups: normal-weight: 0.09(0.43) kg/m(2); overweight: 0.29(0.46) kg/m(2); and obesity: 0.50(0.70) kg/m(2) with significant differences between normal-weight and obesity (p=0.007). After 20 days after Christmas, children with normal-weight were approximated to near values to the first measurement with significant differences (p<0.05) in relation to children whit obesity who were the ones that least decrease their BMI (0.04[0.56] kg/m(2) versus 0.38[0.50]kg/m(2)). Conclusions: Children with obesity showed higher values of BMI than normal-weight children during the non-school period, and they do not recover initial values in relation to normal-weight children.