Weight changes of children in 1 year during COVID-19 pandemic

Introduction: The coronavirus disease 2019 (COVID-19) pandemic has changed everyday life. The Korean government urged schools to close as a measure of social distancing, and children and adolescents seemed to gain weight due to home confinement. We aimed to investigate the trends in weight changes in children during the pandemic period. Materials and Methods: This retrospective study included 139 children aged between 6 and 12 years who visited the pediatric endocrine clinic for regular growth follow-up for 1 year during the COVID-19 pandemic. We analyzed changes in the body mass index (BMI), BMI z-score, and proportion of children who were overweight or obese over a period of 1 year. Results: The BMI and BMI z-scores of the 139 children increased significantly over the year. The increase was maximum during the first three months of the COVID-19 pandemic, with little change between the third and sixth month of the pandemic. The proportion of children who were overweight or obese increased over time, from 24.5% at the COVID-19 pandemic baseline to 38.1% 1 year later (p < 0.001). Conclusions: The COVID-19-related lockdown resulted in significant weight gain in Korean children. Changes in BMI showed different trends depending on the degree of school closure. An overall shift from normal weight to overweight or obesity was observed during the pandemic period.