Dietary Social Norms in School and Home Settings and Their Influence on Children's Healthy Eating: Short-Term Longitudinal Analysis.

Establishing healthy eating (HE) behaviors in childhood is essential for chronic disease prevention. Children's eating behaviors are shaped by social norms of their families, schools, and peer groups, yet the relative influence of these normative sources remains unclear. This study examined the associations between competing dietary norms and children's dietary behaviors. Data were based on the follow-up of a school-based intervention study, with 196 third- and fourth-grade students from eight schools in rural Northern Taiwan. Participants were recruited at the beginning of the fall semester and followed up at 2nd and 4th month after baseline. Children reported their HE behaviors in the last 7 days. Dietary social norms were reported, included: observing adults' HE behaviors at home, perceived expectations of HE from home adults and school teachers, and peer HE norms measured by the class-level average HE behaviors. Observing adults' HE behaviors at home was significantly associated with children's daily milk consumption (OR = 1.57, [95% CI: 1.12-2.19]). Exposed to 10% of children in class adopting a HE behavior during follow-up, a child was more likely to develop FV 5-a-day (OR = 1.21 [1.08-1.36]), not drinking sugar-sweetened beverages (OR = 1.26 [1.14-1.39]), and daily water consumption at school (OR = 1.11 [1.002-1.22]). Children's dietary behaviors were more strongly influenced by observed adult behaviors at home and peer norms than by perceived adults' expectations. Preventive nutrition efforts should prioritize healthy role modeling and supportive peer environments to promote sustained change.