| Highlights: |
Abstract
Food-wasting has a profound negative social and environmental impact. Acknowledging that referring to moral judgment can motivate behavior change, the present study aimed to determine moral intuitions underlying the perception of food-wasting behavior. We developed a set of affective standardized scenarios and we used them to collect behavioral and neuroimaging data. In the main study, 50 participants made moral judgments regarding food-wasting, disgusting, harmful, dishonest, or neutral behaviors presented in these scenarios. We found that wasting food was considered morally wrong and it was associated with moral disgust. Neuroimaging data revealed that food-wasting stimuli elicited an increased activity in structures associated with moral judgment, as well as in regions involved in the processing of moral, but also physical disgust. We discuss our results in the context of the evolutionary significance of food that might have led to seeing food-wasting as a moral transgression.
It is estimated that approximately one-third of all produced food is lost during production and consumption (Gustavsson, Cederberg, & Sonesson, 2011). This problem has profound social and environmental implications. According to the World Economic Forum (2016), food-wasting practices interfere with efforts to establish global food security and may result in future food crises. In addition, food-wasting is associated with food overproduction, which contributes to deforestation and decreased biodiversity through rapidly increasing logging to create pastures and croplands (Houghton, 2012). Moreover, decomposing food is a source of methane which is a much more potent greenhouse gas than carbon dioxide (Melikoglu, Lin, & Webb, 2013). Thus, addressing the problem of food waste from various perspectives is necessary to reduce human malnutrition and biodegradation (Erb et al., 2016; Willett et al., 2019), both of which are among the largest current global risks associated with food-wasting (World Economic Forum, 2016).
Food is lost or wasted in every step of the supply chain. However, in developed countries, the largest waste contributors are direct consumers (Parfitt, Barthel, & Macnaughton, 2010). For example, in the European Union, 89 million tons of food is wasted annually, which is the equivalent to 173 kilograms of food waste per person. Over 50% of this food waste is produced in consumer households (Stenmarck et al., 2016). At the same time, it is estimated that 80% of food waste is avoidable, i.e., it is edible food which is not consumed (Vanham, Bouraoui, Leip, Grizzetti, & Bidoglio, 2015). Studies conducted in the United Kingdom (WRAP, 2007) and Australia (Hamilton, Denniss, & Baker, 2005) on the demographics of food waste show that young people waste more food than older people and that retired families with fewer members waste less food. Education also influences food waste: a lower level of education corresponds to a lower level of food waste (Monier et al., 2010).
However, despite the prevalence of food-wasting behaviors, only recently has this problem been approached from a psychological perspective (Farr-Wharton, Choi, & Foth, 2014; Farr-Wharton, Foth, & Choi, 2014; Graham-Rowe, Jessop, & Sparks, 2015; Kallbekken & Sælen, 2013; Porpino, Wansink, & Parente, 2016; Schanes, Dobernig, & Gözet, 2018; Stancu, Haugaard, & Lähteenmäki, 2016). It has been found, for example, that the largest concerns regarding food-wasting in industrialized societies are of a financial nature (Graham-Rowe et al., 2015; Neff, Spiker, & Truant, 2015; Quested, Marsh, Stunell, & Parry, 2013). Some researchers have begun to view food-wasting as a moral problem (Graham-Rowe et al., 2015; Misiak, Butovskaya, & Sorokowski, 2018). In a qualitative study by Graham-Rowe, Jessop, and Sparks (2014), while respondents were motivated to reduce household food waste principally to save money, moral concerns were indicated as the second-most important motivation. People felt that it was the "right thing to do" to reduce household food waste. When asked why they believed that food-wasting was wrong, participants provided several reasons, e.g., respect for tradition or concern for the environment and future generations.
People in traditional, small-scale societies have been found to associate wasting food with harming others. Misiak and colleagues (2018) hypothesized that moral judgments about food-wasting may serve as an adaptation to harsh ecologies and that populations with higher levels of food insecurity may develop moral norms which prevent people from wasting food. These authors report that the Maasai, who deal with food shortages on a daily basis, tend to compare food-wasting to physical harm (e.g. food-wasting is worse than killing, because killing harms only one person and wasting food may cause more deaths). Nevertheless, a simple statement that wasting food is immoral is not exhaustive. Moral judgment is a complex, non-unitary phenomenon that can be studied in multiple ways, including in a neuropsychological perspective (Awad et al., 2018; Bloom, 2010; Crockett, Siegel, Kurth-Nelson, Dayan, & Dolan, 2017; Graham et al., 2013; Graham, Meindl, Beall, Johnson, & Zhang, 2016; Haidt, 2007; Miller, 2008). Evidence from neuroimaging studies indicate that moral judgment generally involves a wide network of brain areas on both medial and lateral brain surfaces (Bzdok et al., 2012). Brain regions consistently shown to be related to moral reasoning include the Orbitofrontal Cortex, Insula, Amygdala, Cingulate Cortex, and Precuneus as well as the Temporoparietal Junction, Angular Gyrus, Pallidum and Temporal Pole (for a review, see: Boccia et al., 2017; Sevinc & Spreng, 2014). Additionally, different moral domains seem to be associated with distinct neural networks (Chakroff et al., 2015; Lewis, Kanai, Bates, & Rees, 2012; Parkinson et al., 2011; White et al., 2017). This variety is in line with the moral foundations theory, which posits that the human moral system is not unitary but rather based on a set of distinct innate intuitions (foundations), such as disgust towards impurity and contamination, condemnation of causing emotional or physical harm, aversion to dishonesty, disapproval of group disloyalty, and dislike for defying authority and tradition (Graham et al., 2013). In fact, using moral transgression scenarios loosely based on the moral foundations theory as stimuli in an fMRI experiment, Parkinson et al. (2011) demonstrated that different moral transgressions evoked activation in specific brain regions. This research has paved the way for further studies on the neural correlates of distinct moral intuitions. Given the multiple explanations for the negative perception of food-wasting, it remains unclear how the previously mentioned moral foundations are related to moral judgment of this behavior. This issue was investigated in the current study. We were interested in answering the following questions. (1) Is food-wasting considered immoral in reference to other unequivocally immoral categories, such as moral disgust, harm, and dishonesty? (2) Which of these categories of moral intuitions best capture people's moral judgment regarding wasting food? We sought to answer these questions using both behavioral and neuroimaging data. |
