School Breakfast Receipt and Obesity among American Fifth- and Eighth-Graders

Background: School breakfast consumption can improve children's nutrition, but the implications of breakfast at school for children's weight remains unclear. Objective: The aim of this study was to determine whether receiving breakfast at school is related to changes in children's weight between the fifth and eighth grades, and whether the relationship between school breakfasts and obesity varies for children of different socioeconomic backgrounds. Design: This was a longitudinal study of children observed in the fifth and eighth grades. Participants: Data are from the Early Childhood Longitudinal Study, Kindergarten Class of 1998-99, a nationally representative prospective cohort of children in the United States. The analytic sample consisted of 6,495 children interviewed in the fifth and eighth grades. Main outcome measure: Standard thresholds from the Centers for Disease Control and Prevention were used to classify children as not obese or obese based on direct-measured height and weight. Statistical analyses performed: Difference-in-difference propensity score matching and fixed-effect logistic regression models were used to estimate the relationship between receipt of school breakfast and change in obesity between the fifth and eighth grades, adjusting for child, household, and school characteristics. Results: School breakfast receipt was not associated with a change in obesity status between the fifth and eighth grades for children overall (odds ratio=1.31; P=0.129). In the propensity score model, receiving school breakfasts more than doubled the odds of becoming obese (odds ratio=2.31; P=0.0108) for children from families below the federal poverty line compared with children of similar socioeconomic backgrounds who did not regularly receive school breakfasts. Conclusions: School breakfast receipt was not independently related to obesity for most children. Receiving school breakfasts in the fifth grade may be associated with weight gain between the fifth and eighth grades for children from families below the federal poverty line compared with children of similar socioeconomic status who did not receive breakfasts.