Sustainability

Food waste is the origin of major social and environmental issues. In industrial societies, domestic households are the biggest contributors to this problem. But why do people waste food although they buy and value it? Answering this question is mandatory to design effective interventions against food waste. So far, however, many interventions have not been based on theoretical knowledge. Integrating food waste literature and ambivalence research, we propose that domestic food waste can be understood via the concept of ambivalence—the simultaneous presence of positive and negative associations towards the same attitude object. In support of this notion, we demonstrated in three pre-registered experiments that people experienced ambivalence towards non-perishable food products with expired best before dates. The experience of ambivalence was in turn associated with an increased willingness to waste food. However, two informational interventions aiming to prevent people from experiencing ambivalence did not work as intended (Experiment 3). We hope that the outlined conceptualization inspires theory-driven research on why and when people dispose of food and on how to design effective interventions.

Many people are aware of the negative consequences of plastic use on the environment. Nevertheless, they use plastic due to its functionality. In the present paper, we hypothesized that this leads to the experience of ambivalence—the simultaneous existence of positive and negative evaluations of plastic. In two studies, we found that participants showed greater ambivalence toward plastic packed food than unpacked food. Moreover, they rated plastic packed food less favorably than unpacked food in response evaluations. In Study 2, we tested whether one-sided (only positive vs. only negative) information interventions could effectively influence ambivalence. Results showed that ambivalence is resistant to (social) influence. Directions for future research were discussed.

Eating less meat would benefit environmental sustainability, human health, and animal welfare. Providing information about this, however, does often not lead people to adopt according beliefs, attitudes or behaviors. In fact, dietary changes are often prevented by dissonance reduction (i.e. moral disengagement) if information elicits a conflict regarding meat. In the present investigation we thus aimed to address moral disengagement via a communication strategy that consisted of two stages: In Stage I, we presented information by showing distressing scenes from animal agriculture. In Stage II, we then counteracted moral disengagement in a dialog. Two studies indicate that, following the dialog, people’s evaluations of meat changed and their willingness to eat meat decreased; this seemed to result from lowered moral disengagement. By providing an empirically tested communication strategy for addressing moral disengagement on the exemplary conflict regarding meat, we hope to inspire research and interventions that intend to communicate (environmental) issues.

Why is it that people do not change their behavior in the face of global threats? We hypothesized that when people who have been encouraged to engage in pro-environmental behavior are threatened, they fall back into their (bad) habits instead of exhibiting behavioral change; existential threat may thereby counteract pro-environmental norms. We tested this hypothesis in two field studies in which participants were encouraged to reduce paper use. Although the requests initially resulted in decreased paper use, this pro-environmental behavior ceased when an existential threat was induced. We discuss theoretical and practical implications for social psychology theorizing and behavioral change.