It’s a strange and sometimes unsettling phenomenon: people adapt to things that many of us find disgusting or immoral. It’s often referred to as desensitization, and we see it happen around us in ways that are both trivial (perhaps someone watching horror movies becomes inured to their content) and more serious.

In this study, researchers looked at butchers and deli workers, and their attitudes towards animal agriculture and meat. They hypothesized that working with meat over time engenders a kind of numbing effect, in which things that are initially repulsive become normalized. Furthermore, they believe that people who work with meat shape their beliefs to justify the industry, including reducing empathy for the animals that are killed.

Two groups were formed, one consisting of a control – people without any experience working with meat – and one with people who worked with meat in some way as a butcher or deli employee. All participants were located in the United Kingdom, within Lancashire, in the United Kingdom. Of the meat workers, the majority worked in delis, butcher shops, or other kitchen/food services. Time worked in the industry ranged from under six months to over 20 years. Demographic information for both groups was collected, as well as their self-reported diet. Overall, both the meat workers and the control group had roughly similar diets. 

Participants were shown images of meat products at various stages of production and from various animals. They were asked to report their feelings of disgust towards the picture, empathy for the animal, and whether they associate the image with an animal. Afterwards, participants were shown a list of 27 animals, including humans, and were asked to circle those which they believed they were morally obligated to show concern for. This task was done to determine the “moral circle” of participants. Next, participants’ justification for meat consumption was assessed through an agree/disagree questionnaire. The questionnaire covered what are called the “Four Ns” – meat is Natural, Normal, Necessary, and Nice. Sixteen statements were shown that endorsed one or more of the Ns, and participants ranked their level of agreement. Finally, the participants were judged on their level of support for humane slaughter, their belief that animals are treated humanely, and their belief in human supremacy over other animals. 

Age was positively correlated with support for the Four Ns and beliefs in human supremacy and humane treatment, as well as support for humane slaughter. Older participants also reported less disgust, empathy, and animal association. For this reason, age was treated a covariable in the study. Disgust and empathy decreased with level of experience working with meat. There was no major effect of animal type – fish, cow, or sheep. – but a significant effect of “animal reminder level” – how much the meat product resembled the animal. Animal reminder level was also, unsurprisingly, associated with a higher level of meat-animal association. Meat handling experience was also associated with higher levels of support for the 4Ns and human supremacy, as well as a more restricted moral circle. 

This results of this study suggest that there is indeed a “numbing effect” to working with meat, as people with significant experience working in butcher shops and delis reported less empathy and disgust with meat, as well as greater endorsement of human supremacy and belief that animals are treated humanely when farmed. The authors offer several possible reasons for this, including that repeated exposure decreases sensitivity (which backs up something many likely believe intuitively), or that meat workers shape their beliefs around their occupation to justify their actions. 

For advocates, this is evidence that reliance on disgust-based arguments might be counterproductive. If people are routinely exposed to what they currently consider disgusting, they may simply become adapted to the stimuli and find it less bothersome. Advocates should use methods that maintain or grow in strength with repeated exposure, rather than ones that become less-effective over time.