Interpersonal influences on adolescents’ healthy and sustainable eating behaviour: A mixed-methods study in the Dutch school context

Background: Introducing healthy and sustainable food into the unique life stage of adolescence is essential. Interpersonal factors are shown to influence adolescents’ eating behaviour, however, more insight is needed into adolescents’ views on these factors. Therefore, this research aims to gain insight into interpersonal influences related to Dutch adolescents’ healthy and sustainable eating behaviour from the perspective of adolescents themselves.
Methods: This study had a mixed-methods design and included four participating secondary schools (n=314). Eight focus groups (n=48) were conducted and analysed using secondary deductive thematic analysis on interpersonal influences on eating behaviour. 152 students completed a survey including twenty-five items (five-point Likert scales) on healthy and sustainable eating behaviour and interpersonal factors. Differences were calculated using t-tests in R.
Findings: Students perceived eating healthy as being more important than eating sustainably (3.8±0.8 and 2.9±1.1; P<0.05). Family injunctive norm on healthy eating scored higher than peer injunctive norm (3.9±1.1 and 2.6±0.9; P<0.05). While peer support through talking about healthy eating was perceived low (1.9±0.9), peer acceptance was high (4.2±1.0). A similar picture was found for sustainable eating. Focus groups showed that most students acknowledged parents stimulating their healthy eating behaviour through the home environment. Contrarily, eating with peers during school hours was associated more with having fun, and less with the type of food consumed.
Discussion: While parents seemed to positively influence students’ eating behaviour, peer influences were more mixed. High peer acceptance and low peer support show potential to improve adolescents’ eating behaviour through enhancing peer support and norms.