Reducing animal product consumption for a more sustainable food system: the potential power of social influence

Abstract

A more sustainable food system is needed to mitigate environmental issues, social inequalities, and health risks. Reducing animal product consumption – the consumption of meat, dairy, fish, seafood and eggs - can play a key role in this transition. Research into determinants of and strategies to change animal product consumption is therefore crucial. These determinants can be divided in four different levels or categories: personal, social, contextual and macro-level. While eating behavior is known to occur in the social context and to be influenced by our social environment, previous research has largely neglected social factors. Research on the social environment in relation to animal product or meat consumption has solely represented the social environment by perceived social norms, or researched simple associations between the social environment’s animal product consumption behavior and the own. Following a social network perspective, social influence can go beyond social norms, and social network dynamics are more complex than associations. In addition, strategies leveraging the social network in interventions have shown to be successful in changing other eating behaviors, but have not been applied to animal product consumption. Therefore, this dissertation assessed the potential power of social influence to reduce animal product consumption. Several objectives were identified and each was addressed in one chapter: (1) Creating and testing a conceptual model of the psychological mechanisms through which the social network influences animal product consumption, using egocentric network data (chapter 2). (2) Assess the social dynamics that are operating in the relationship between a social network and animal product consumption, using sociocentric network data and an advanced social network analysis method - Stochastic Actor-oriented Modelling (chapter 3). (3) Testing the effectiveness of a social network intervention leveraging social influence in reducing animal product consumption (chapter 4). Results of the first study in chapter 2, using Partial Least Squares – Structural Equation Modelling indicate that close social contacts’ reduction of animal product consumption is related to attitude, perceived behavioral control, social norms and awareness of environmental consequences regarding animal product consumption. These constructs, except social norms, are related to personal norm (i.e., internalization into a personal norm). Personal norm, but not intention, predicted animal product consumption behavior. The second study (chapter 3) focused on a friendship network of Dutch students. Findings indicate that in the timespan of a year, student friends did not influence one another’s animal product or meat consumption, but meat consumption was influenced by having meat-reducing household members. Students preferred friends with a similar dietary identity (i.e., vegetarian or not) and friends with a lower animal product consumption in general. Finally, the intervention study in chapter 4 tested the effectiveness of an app-based challenge to reduce animal product consumption for 30 days and compared a social to an individual approach. The social treatment was encouraged to involve family and friends throughout the challenge (i.e., seek social support). Results show that both the individual and social treatment were effective, but that only the results of the social treatment lasted at least until three months after the intervention. The answer to the dissertation’s main objective is that social influence can play a role in reducing animal product consumption, based on the following four conclusions: (1) close social contacts tend to be similar in terms of animal product and meat consumption, as evidenced by multiple studies in this dissertation; (2) social influence on animal product consumption goes beyond social norm, considering the relationships with other psychological perceptions (i.e., attitude, perceived behavioral control, awareness of consequences and personal norm); (3) animal product consumption, and dietary identity in particular, are intertwined with social relationships and network structures, as evidenced by the selection of friends with a similar dietary identity; (4) social influence can be a powerful tool to increase the effectiveness of an intervention to reduce animal product consumption, by simply including an encouragement to involve the social environment in the behavior change process. As the studies also had some limitations, discussed in the last chapter, it is recommended that future studies extend the research on the topic of social influence on animal product consumption. Practically, it would be useful to test and implement more social network-based interventions. Altogether, this dissertation forms a basis for the topic of how the social environment relates to animal product consumption behavior, and how we can leverage the social environment to accelerate the transition towards plant-based diets.