The Psychology Of Vegetarianism

It seems like more and more people are going vegetarian nowadays, giving up meat and jumping aboard the bandwagon of plant-based dieting. Shifts in consumer preferences are accompanying the introduction of new plant-based products, from lab-grown meat alternatives to a plethora of dairy-free milk, cheeses, and ice creams.

Vegetarianism has long garnered interest from the academic fields of philosophy and nutritional science, as philosophers ponder the ethics of whether or not people should eat animals as meat, and as nutritional scientists investigate whether vegetarian dieting holds the key to optimal health. Yet the food choices we make reflect more than our philosophical stances and impact more than our physical health — rather, what we eat plays a powerful role in a wide range of psychological phenomena that shape how we think about ourselves and our everyday social experiences. In a recent review paper in the journal Appetite, I summarize what more than 150 studies have revealed about the psychological nuances of vegetarianism.

First off, it’s helpful to understand what vegetarianism is and why people subscribe to it. Vegetarianism is broadly defined as the practice of refraining from eating meat. But a lot of different types of vegetarian diets exist, varying in how restrictive they are. At the less restrictive end of the vegetarian continuum are pescatarians — those who don’t eat red meat or poultry but do eat fish. Since fish is technically considered to be a form of meat, though, a debate does exist as to whether pescatarians are truly a type of vegetarian. The prototypical vegetarian is what we’d call a lacto-ovo vegetarian, or someone who doesn’t eat any form of meat but does eat egg and dairy products. At the more restrictive end of the vegetarian continuum are vegans, those who refrain from eating any animal products.

Just as vegetarians are a diverse group of folks in terms of what foods they will or won’t eat, so too are they diverse in terms of their dietary motivations. Psychologists have taken a keen interest in understanding what motivates people to go vegetarian. In a culture, such as the United States, where the overwhelming majority of people eat meat, it almost always takes some specific motivation to propel people to go vegetarian. Reviewing many studies in which researchers have surveyed vegetarians on their motivations, I found that the three most common reasons why people go vegetarian are for (1) animals, (2) its health benefits, (3) and its lower impact on the environment.

Personally, as a psychology researcher, I think it’s fascinating to think about what motivates people to eat in certain ways. But more than that, why does it matter whether someone eats a vegetarian diet for one reason or another? Does that tell us anything important about their attitudes, behaviors, or other psychological phenomena? It most certainly does. A number of studies have suggested that what motivates someone to go vegetarian effects how disgusted they are by meat, how strictly they adhere to their diets, and even what attitudes meat-eaters have toward them.

A recurrent finding across studies is that many vegetarians actually eat meat on occasion. Not only does this paradox challenge the precise definition of a vegetarian, but it also begs the question of why some vegetarians follow their diets strictly while others follow their diets more flexibly. Apparently, motivation matters quite a lot when it comes to dietary adherence. Specifically, vegetarians who follow their diets out of a moral concern for animals are much more likely to follow their diets strictly than are vegetarians motivated by either health or environmental reasons. Why might this be? Why would someone’s motivation for giving up meat influence how closely they stick to that dietary aim?

Research suggests that a probable factor is disgust: Vegetarians motivated by a concern for animals feel more disgusted by meat, and that greater feeling of disgust may lead them to follow their diets particularly strictly. Health-motivated and environmentally motivated vegetarians, meanwhile, aren’t so grossed out by meat. One reason for this may be related to what psychologists call animal-meat association. The fact that meat comes from animals is, well, rather disgusting to many people, so people like to forget that meat comes from an animal — that is, they dissociate meat from its animal origins.

People who go vegetarian for animal rights or welfare, on the other hand, tend to view the meat people eat as a direct product of the animals from which that meat came. Linking meat to its animal origins elicits a disgust response, and disgust is a powerful emotion that informs what foods we’re willing to eat or not eat. If you’re grossed out by a food, that’s basically evolution’s way of telling you that eating that food probably isn’t the safest move.

What motivation a vegetarian has for giving up meat can also affect what attitudes meat-eaters have toward him or her. It’s true that some meat-eaters don’t have the fondest views toward vegetarians. Yet a vegetarian’s motivation matters: Meat-eaters tend to have the most positive attitudes toward health-motivated vegetarians, more negative attitudes toward environmentally-motivated vegetarians, and the most negative attitudes toward animal-motivated vegetarians. Although meat-eaters generally have positive impressions of vegetarians overall, many meat-eaters do have negative biases against vegetarians, holding a range of unfavorable stereotypes about those who choose a plant-based diet.

But why might meat-eaters disparage vegetarians who give up meat for animals and the environment the most, more than vegetarians who do so for health? A probable reason is that animal and environmental motivations are moral motivations. By giving up meat, vegetarians inherently challenge the omnivorous status quo, and challenges to conventional views of morality may be more threatening than challenges to norms about health. Essentially, morally motivated vegetarians are threatening to some meat-eaters, as they inherently make salient the question of whether it is right or wrong to eat meat. Some research has found that meat-eaters think vegetarians are judgmental — much more judgmental than vegetarians truly are — and this unfounded belief can cause meat-eaters to denigrate vegetarians as a means of defending their own self-image from imagined moral threats.

Matters of morality aside, the fact that people possess distinct beliefs about and stereotypes toward vegetarians, along with the paradoxical fact that many people call themselves vegetarian yet eat meat from time to time, have led psychologists to propose the notion that being a vegetarian is intertwined with one’s sense of identity. More than that, though, many psychologists believe that vegetarianism is its own distinct social identity. A social identity characterizes a way in which one sees oneself as a member of some social group. Vegetarians and meat-eaters can be thought of as two different social groups, defined by whether or not they eat meat. An analogy can be made to the way in which political orientation is a form of social identity. Liberals and conservatives are two different social groups, and depending on a person’s political beliefs, he or she may identify with one of these groups and thus form a political social identity. Quite literally, vegetarianism embodies the common saying that “you are what you eat” — though I suppose a more accurate spin-off may be “you are what you don’t eat.”

Thinking of vegetarianism as a social identity can help us understand a number of important issues. It may provide a framework for thinking about how some vegetarians eat meat occasionally, as we realize that people may construe vegetarianism as a way of seeing themselves rather than as a strict dietary pattern they’re obliged to follow absolutely. In another sense, it may make sense of a related paradox that some folks who follow a strictly vegetarian diet don’t like calling themselves vegetarian — it’s an identity they don’t want to take on, perhaps because it’s highly stigmatized in certain cultures. What’s more is that some vegans refrain from calling themselves vegetarian, seeing veganism as totally distinct from vegetarianism. Without considering identity aspects of eating behavior, the study of vegetarian dietary patterns can become rather messy.

Yet beyond these matters, considerations of vegetarianism as an identity are critical to understanding intersectionality — namely, how people of varying races, ethnicities, gender identities, religions, sexual orientations, and socioeconomic statuses may think about the idea of being a vegetarian in drastically different ways. These core aspects of an individual’s identity may influence how they construct a sense of identity around their eating behaviors.

Relative to its history within philosophy and nutritional science, vegetarianism as a topic of psychological science is in its youth with great promise for the years to come. As concerns about the health, ethical, and environmental sustainability implications of meat consumption continue, food systems and eating practices are bound to evolve. By studying the psychology of vegetarianism, we can generate deeper meaningful insights into not only why people eat the way they do but also how their eating behaviors shape their senses of identity and morality.

These findings are described in the article entitled The psychology of vegetarianism: Recent advances and future directions, recently published in the journal Appetite. This work was conducted by Daniel L. Rosenfeld from UCLA.