Measuring, understanding, and reducing food disgust

: the example of entomophagy

Abstract

Disgust in relation to food is a universal emotional experience. Generally, disgust functions to orient humans away from harm, but in some instances, it is induced in the absence of a threat, which can be problematic. For example, in Western cultures, the thought or act of eating insects (entomophagy) will induce disgust in most people, despite many species of insects being high in protein and other essential nutrients. This is an issue because edible insects, along with other alternative proteins, have health and sustainability advantages compared to conventional sources of animal protein.
The primary aims of the work in this thesis were to understand how food disgust affects appetite and causes food rejection, and to use the results of this understanding to inform the development of interventions to reduce food disgust. These investigations were preceded by work which tested methods to explicitly, and implicitly, detect food disgust.
Throughout the thesis, entomophagy was used to induce food disgust. It was found that self-reports of experienced food disgust were a useful, and easily applied, measure of food disgust. Latency to eat and food intake were reliably affected by experienced food disgust – together with self-reports, these measures can be used to detect experienced food disgust. Chapter 4 directly investigated how disgust affects appetite and causes food rejection, though insights from Chapters 3 and 5 provided further clarity on this. Contrary to the long-standing theory of food disgust, the disgusting foods were not rejected because they were perceived as tasting bad (unpleasant). Instead, the evidence suggested that disgusting foods are rejected due to low food wanting. These insights led to a new conceptualisation of food disgust that proposes that our knowledge of the origin or nature of a food (our ideation) affects both food liking (taste pleasantness) and food wanting, which in turn affect disgust, and can cause food rejection. In Chapter 5 it was found that a descriptive social norm intervention reduced disgust and increased the acceptance and intake of whole crickets.
Further research on the contribution of low wanting to food disgust, and on the application of social norm interventions to reduce food disgust, is warranted.

Date of Award	3 Oct 2023
Original language	English
Awarding Institution	University of Bristol
Supervisor	Peter J Rogers (Supervisor) & Danielle Ferriday (Supervisor)