Expanding the theory of planned behavior to explain energy dense food intentions among early adolescents in Indonesia

The aim of this study is to examine an extended model of the Theory of Planned Behavior (TPB) and increase insight into the intentions to consume energy-dense food among adolescents in Indonesia. This study included 411 adolescents from private schools who reported their intentions to consume energy-dense food the next day and the next week, as well as attitudes, subjective norms, descriptive norms, and perceived behavioral control regarding energy-dense food consumption. Linear regression analyses (in R) were conducted to examine associations of TPB determinants (model 1), TPB determinants plus descriptive norms (model 2), and interactions between determinants (model 3) with the intention to consume energy-dense food the (1) next day or (2) next week. Attitudes and subjective norms were positively associated with both the 'next day' and 'next week' energy-dense food intentions (model 1), although associations for the 'next day model' appeared to be stronger. Descriptive norms, compared to subjective norms, were more strongly associated with 'next week intentions', whereas both norms (descriptive and subjective) did not differ in how strongly they were associated with 'next day' intentions (model 2). Significant interactions between TPB constructs were found for the model predicting 'next day' intentions (i.e. subjective norms x attitude and attitude x PBC) (model 3). Our study provides important information about proximal food intentions among collectivistic cultures specifically, which may have crucial implications for future preventive interventions.