Explaining the adoption of sustainable diets and healthy diets among German consumers via an extended comprehensive action determination model

This study builds upon and extends the abridged comprehensive action determination model to predict self-reported eating behaviors among a sample of German consumers. It focuses on two related but conceptually distinct facets of eating behaviors: healthy eating and sustainable eating. Specifically, the role of health consciousness, attitude, perceived behavioral control, and social and personal norms for the adoption of healthy diets, as well as the role of environmental concern, perceived consumer effectiveness, awareness of need, self-efficacy, attitude, perceived behavioral control, and social and personal norms for the adoption of sustainable diets are assessed. A longitudinal design was applied and data from 620 German residents were collected, with the two data collections being 4 weeks apart. A path analysis showed that (i) attitude, social and personal norms relate positively to healthy eating; (ii) social and personal norms but not attitude relate positively to sustainable eating; and (iii) perceived behavioral control is unrelated to both healthy and sustainable eating. The variables explain 35 % of the variance in healthy eating and 27 % of the variance in sustainable eating. This study highlights that respective beliefs and norms predict both facets of eating behaviors. These predictors can be influenced by public policy campaigns, media, and communications. • We test an extended abridged comprehensive action determination model. • Outcomes are sustainable eating and healthy eating among German consumers. • Attitude, social and personal norms relate positively to healthy eating. • Social and personal norms but not attitude relate positively to sustainable eating. • Perceived behavioral control is unrelated to both healthy and sustainable eating.