Abstract
BACKGROUND: Fast food is cross-sectionally associated with having overweight and obesity in young children. OBJECTIVES: To examine whether fast food intake independently contributes to the development of overweight and obesity among preschool-age children. METHODS: Prospective cohort of 3- to 5-year-old children (n = 541) followed for 1 year. Children's height and weight were objectively measured at baseline and study end. Parents reported their child's fast food intake frequency in the past week from 11 chain fast food restaurants in six online follow-up surveys, completed approximately 8 weeks apart. Poisson regression with robust standard errors modelled the risk of a child increasing in weight status (ie, transitioning from a having a healthy weight to having overweight or from having overweight to having obesity) over the study period in relation to their average weekly fast food intake, adjusted for sociodemographics, child obesogenic behaviours, and parent weight status. RESULTS: At baseline, 18.1% of children had overweight and 9.8% had obesity; 8.1% of children transitioned to a greater weight status over the 1-year period. Mean fast food intake frequency among consumers was 2.1 (SD: 1.4) times per week. The risk of increasing in weight status increased linearly with each additional time fast food was consumed in an average week over the study year (RR: 1.38; 95% CI, 1.13-1.67; P < .01). CONCLUSIONS: Greater fast food intake over 1 year was associated with increasing weight status during that time in this preschool-age cohort.