Changes in Body Mass Index during the COVID-19 Pandemic among Indonesian Adolescents: The Role of Sex, Urban Area, Baseline BMI, and Appetitive Traits

Introduction: Little is known about how the COVID-19 situation affected weight development among Indonesian adolescents. This longitudinal study examined whether, and for whom, the COVID-19 situation affected weight outcomes over time among adolescents from private schools and higher socio-economic positions in Indonesia, where being overweight is a rather prevalent characteristic. This study specifically examined whether appetitive traits (i.e., emotional overeating, food responsiveness) as well as baseline zBMI, sex, and urban area could explain changes in zBMI. Methods: At baseline, 411 adolescents from 5 private schools in Indonesia (53.3% males, Mage = 12.02 years, SD = 0.45) filled out questionnaires on appetitive traits and background characteristics. In addition, their height and weight were measured. Of these, 336 adolescents (81.8%) also participated at follow-up. At follow-up, height and weight were measured or reported. We used linear regression to analyze the association between predictors and interactions with zBMI. Results: The results showed a significant decrease in zBMI over time, with a lower average zBMI during COVID-19 compared to before COVID-19. Female adolescents and adolescents with higher baseline zBMI values particularly tended to show this zBMI decreasing pattern. We did not find statistically significant main effects of baseline emotional overeating, food responsiveness, and urban area or any interactions. Conclusions: Indonesian adolescents appeared to decrease in terms of zBMI during COVID-19, particularly females and adolescents with higher pre-COVID-19 zBMI. Our findings suggest that (culturally-specific) contextual changes (i.e., less exposure to the Indonesian food environment at schools and more exposure to the home environment) might have a beneficial impact in terms of preventing overweight among Indonesian adolescents, particularly among those being more vulnerable (i.e., having higher baseline zBMI).