Sustainable diets: Links between knowledge, motivations and food practices

To preserve the planet's ecosystems and ensure the well-being of its inhabitants, the adoption of more sustainable diets is necessary. At present, however, consumer dietary practices often remain unsustainable. One main barrier to adopting sustainable diets is the lack of both knowledge and motivation. The primary objective of this study was to examine whether a link exists between knowledge about sustainable diets and sustainable eating practices, and whether this link is mediated by motivations. Additionally, we compared the respective roles of objective and subjective knowledge about sustainable diets. To this end, 273 participants aged 20 to 60 years responded to questionnaires about their motivations concerning sustainable food choices, as well as their objective and subjective knowledge about sustainable diets, and their self-reported sustainable eating practices. A PLS-SEM model was used to analyze the relationships among these variables, demonstrating good reliability of the indicators, internal consistency, convergent and discriminant validity, and no multicollinearity. The predictive power of this model was found to be satisfactory, with 18% of the variance explained for motivations and 34% for practices. Our results indicate a significant link between knowledge about sustainable diets and sustainable eating practices, with motivations acting as a crucial mediator in this relationship. This finding was confirmed for both objective and subjective knowledge. Subjective knowledge was thus also revealed to have a direct effect on sustainable eating practices. These findings suggest that the manner in which individuals perceive their own knowledge about sustainable diets may have a greater impact on their practices than their actual knowledge, and that motivations play a central role in shaping sustainable behaviors.