Relationship between motivations and dietary behaviours within parent-adolescent dyads: Application of actor-partner interdependence models

BackgroundParents play a substantial role in improving adolescent dietary behaviours.ObjectivesTo examine the interdependent relationships between motivations (autonomous and emotional motivation) and dietary behaviours (fruit and vegetable [F/V] and junk food and sugar-sweetened beverage [JF/SSB] intake) within parent-adolescent dyads.MethodsThis secondary data analysis was conducted on 1522 parent-adolescent dyads using a cross-sectional Family Life, Activity, Sun, Health, and Eating (FLASHE) study. The ratio of boys to girls among the adolescents was approximately equal, and 74% of the parents were mothers. The adolescents were between 12 and 17 years old, and 85.5% of the parents were between 35 and 59 years old. Parents and adolescents completed an online survey on dietary motivations and behaviours. Actor-partner interdependence models were performed within parent-adolescent dyads.ResultsF/V and JF/SSB intake was influenced by parents' or adolescents' autonomous motivation (actor-only pattern), except among adolescents with obesity. A dyadic pattern was found in the relationship between autonomous motivation and F/V and JF/SSB intake, but only among adolescents with normal weight. No relationship was found between F/V and JF/SSB controlled motivation and F/V or JF/SSB intake among adolescents with overweight or obesity.ConclusionsAutonomous motivation had a significant relationship with F/V and JF/SSB intake for both parents and adolescents, but the association varied depending on the adolescents' weight. Personalized programmes that foster autonomous motivation to change dietary behaviours should be provided based on the adolescents' weight status.