Why We Know So Little About the Psychology of Eating in Humans

Abstract

Considering the major importance of human food and eating in human life, it is surprising how little we know about the psychology of it. The area of human eating is divided into understanding how much humans eat and what humans eat. After massive efforts and expenses, by excellent researchers, we have been very unsuccessful at treating obesity, the major “how much” disorder. We have barely attempted to understand or treat the very common phenomenon of picky eating, the major disorder associated with what we eat. In accord with Herman et al. (Social influences on eating. Springer, Cham, 2019), it is argued that for how much, we have in large part been looking in the wrong place. Multiple, situational (institutional), social, and cultural factors are the principal determinants of how much humans eat. Major research efforts on animal eating, motivated by a homeostatic model, have taught us much about animal food intake regulation and informed us about the physiology and psychology of a similar system in humans. But that system accounts for a small minority of the variance in human food intake. To understand what we eat, there is no homeostatic model, and animal data are understood to be minimally relevant. The roles of context and social-cultural-cognitive factors are much more obvious for what humans eat than for how much they eat. Probably, for these reasons, there has been little motivation in psychology to work on food choice. For future work on both how much and what we eat, we should value observation more, focus more on human and less on animal research, less on experiment and more on multiple variables operating together, and less on laboratory settings and more on the real world. Psychology is good at experiments, at isolating causal factors, and at constructing scales to measure beliefs and attitudes. These important skills can be combined with the orientations of sociology and anthropology to yield optimal progress.