Trajectory of Obesity and the Impact of Eating Behaviors on Obesity in Preschool Children: A Nationwide Population-Based Cohort Study in Korea

<b>Background</b>: Early childhood obesity is highly associated with obesity in adolescents and adults. However, studies on specific eating behaviors that have a decisive effect on obesity in early childhood (aged 3-5 years) are scarce. We hypothesized that critical risk factors associated with eating behaviors leading to obesity at ages of 3-5 years may be different. To confirm this hypothesis, we conducted a study on the risk factors of obesity related to eating behaviors in preschool children. <b>Methods</b>: Using the National Health Screening Program for Infants and Children (NHSPIC) in Korea's general population cohort, we found the obesity trends in 3-5-year-olds. The risk factors of obesity in 3-5-year-olds were analyzed through logistic regression. <b>Results</b>: Among children with obesity at 3 years old, but without obesity at 4 years old, only 10.1% (107/1063) transitioned to obesity at 5 years old, whereas among children with obesity at 3-4 years old, 62.7% (398/635) transitioned to obesity at 5 years old. The risk factors for obesity at 3 years old were inclusion of meat in complementary food, prolonged breastfeeding, and consumption of sweetened beverages; at ages 4-5 years, the risk factors were the inclusion of meat in complementary food and consumption of sweetened beverages. <b>Conclusions</b>: Obesity at 4 years is more likely to lead to obesity in the following year than obesity at 3 years. The dietary factor with the greatest impact on obesity in children aged 3-5 years has been found to be consumption of sweetened beverages.