Body mass index and prevalence of metabolic syndrome among Korean adults before and after the coronavirus disease 2019 outbreak: a retrospective longitudinal study.

Metabolic syndrome, its components, and fat distribution worsened significantly after the implementation of social distancing and lockdowns, despite no clinically significant changes in body weight and BMI. Further studies on the post-pandemic period should investigate the long-term impact of social lockdowns on BMI and the prevalence of metabolic syndrome.