Résumé
We carried out several studies concerning the factors influencing the consumption of animal foodproducts. Three of their major results are mobilized in the present study. The first result wasobtained from a survey carried out in the VITAMIN project[1] on 1,715 French respondents, abouttheir food choices. It revealed that 40% of respondents’ current diet is not their ideal dietregarding animal product consumption, which they would like to reduce. The second result wasobtained from the analysis of 20 indepth biographical interviews carried out in the VITAMINproject. These showed that social pressure was a major factor for abandoning the adoption ofmeatless diets. The third result was obtained from an experimental protocol carried out by thePNCA lab. It tends to show that social norms, and especially the subjective social norm, arehindrances in the short term too and influence the food choices made during a meal. Hence, inthese studies, daily food choice in the short term is opposed to the “ideal" choice in the long termtowards a reduction in meat consumption. This is where social norms seem to be an importantsource of inertia.In the present work, we hypothesize that social acceptance of less meaty diets isunderestimated, that is to say, that the perception of the social norm is biased. We propose amodel, implemented in the GAMA agent-based simulation platform, in which two situations areconsidered. At home, individuals’ food consumptions are supposed to be conform to their desiredfood diets (this is a simplification, since factors such as cultural habits, appetite for meat, choice ofmeals by another member of the family, etc., can interfere). Outside the home, individuals’ foodconsumptions are supposed to be modulated by the perceived social norm - a global numericalvariable reflecting the population’s total meat consumption outside the home. During a simulation,some individuals start to consume outside the home according to their desired food diet. We studythe effect of this change on the whole population over time.