Changes in body mass index in children and adolescents in Israel during the COVID-19 pandemic.

The COVID-19 pandemic correlated with overall weight gain among children and adolescents, with the most substantial weight gain in children aged 2-6 years. Notably, the most significant increase in BMI-SDS was observed in children with underweight; BMI-SDS decreased in children with overweight and obesity. Policies should be established during the pandemic that focus on increasing physical activity, reducing sedentary time, and promoting healthy diets.