Introduction: The COVID-19 pandemic has led to a biopsychosocial health deterioration in children and adolescents. However, there is a lack of knowledge about its impact on weight status. This study aimed to assess the body mass index trends in children and adolescents over more than one year of the COVID-19 pandemic. Moreover, this research examined the association of “children and adolescents” overall body mass index changes with psychological distress and specific household characteristics.
Methods: This cross-sectional study with a retrospective component was carried out in a Portuguese hospital with a convenience sample of 422 children and adolescents (mean age = 12.4 ± 2.9 years) and one of their parents. A validated online questionnaire was administered to both groups to evaluate their psychological distress. Multiple linear regression was used to identify the body mass index change predictors.
Results: The COVID-19 pandemic has caused weight gain in children (p < 0.001), increasing the prevalence of overweight and obesity. The first lockdown alone accounted for the observed results, as the remaining time was characterized by a gradual decrease in body mass index, though insufficient to reach pre-pandemic levels (p = 0.015). Associated factors included “children and adolescents” body mass index, stress, and specific household characteristics.
Discussion: This study contradicted the hypothesis that weight would increase proportionately to the number of months of school closure. It also underscores children’s difficulties in losing the weight gained during the first lockdown. Finally, the association of weight gain with environmental and psychological factors highlighted the importance of their consideration in the therapeutical approach towards excessive weight gain.