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  • Writer's pictureMeg

The Psychology of Food Choices

Updated: May 29, 2022

“We don’t see things as they are; we see things as we are” – Anis Nin

As soon as I stopped eating meat something very interesting happened; I started seeing meat for what it is – the flesh of a dead animal, not so dissimilar to my own flesh. But what was even more interesting was the number of people who thought that I would feel that I was “missing out” by abstaining from eating these disgusting products.

Melaine Joy is a Professor of Psychology and Sociology at the University of Massachusetts, who has studied these phenomena. In her book Why we love dogs, Eat pigs and Wear Cows Melaine coined a term for an invisible, violent ideology (or belief system) in which people believe it is ethical to eat animals - carnism.

“Carnism is essentially the opposite of veganism, as “carn” means “flesh” or “of the flesh” and “ism” refers to a belief system. Because carnism is invisible, people rarely realise that eating animals is a choice. In meat-eating cultures around the world, people typically don’t think about why they eat certain animals but not others, or why they eat any animals at all. But when eating animals is not a necessity, which is the case for many people in the world today, then it is a choice – and choices always stem from beliefs. As long as we remain unaware of how carnism impacts us, we will be unable to make our food choices freely – because without awareness, there is no free choice”. - Melanie Joy

But why might this be the case?

Cognitive Dissonance

One of the first things I learn in cognitive psychology was about cognitive dissonance. Humans are said to strive for internal consistency, in which all behaviour is ideally in line with our values and beliefs. When there is an inconsistency between our values and beliefs and our behaviours there is a feeling of discomfort which may manifest itself in anger or fear or be alleviated by criticising others or justifying the behaviour in some other way.

The more you look for examples of this phenomena, the more you can find it in everyday life. I tend to see it a lot in my work as a drug and alcohol case manager and group facilitator, but there are few of my own I have experiences recently. For example, the previous car I had was not very fuel efficient (behavioural choice) however, I strive to have a small carbon footprint on the environment (value), this caused me mild discomfort (which I justified this for a time, as being vegan makes my carbon footprint significantly less than the average Aussie).

Cognitive dissonance applies to meat eating as show in the below image I saw recently.


Cognitive Psychology

A schema is a cognitive phenomenon which describes the mental structures we use to organise and simplify our knowledge of the world around us. Melanie Joy explains that our carnistic schema dictates which animals are edible and which are inedible and indeed whether we eat animals or not. Our schema, including a carnistic schema, also filters information we receive throughout our lives.

People have a tendency to be biased in various ways, one such way is named confirmation bias. Through a carnistic schema, Melanie explains that people selectively allow in information that confirms we are justified in eating animals and distorts information that threatens otherwise. An example of this from my own life was when I cried seeing footage of factory farming shortly after going vegan and my partner attempted to comfort me by saying that type of cruelty only occurs in Asia and America. This thought process highlights my partner’s filtering of information though his carnistic schema to protect him from thinking about the animal cruelty and rights violations that are alive and well in Australia today.

The carnistic ideology teaches us to distort our perceptions of the animals we eat so that we can feel comfortable enough to consume them. We learn to view farmed animals as objects, referring to farmed animals as something, rather than someone and as abstractions, lacking any individuality or personality.

“Whether we’re talking about fish species, pigs, or some other eaten animal, is such suffering the most important thing in the world? Obviously not. But that’s not the question. Is it more important than sushi, bacon, or chicken nuggets? That’s the question” – Jonathan Safran Foer, Eating Animals

Emotional Psychology

There are around five primary emotions, one of which is disgust. To my knowledge, disgust has the evolutionary advantage of protecting us from consuming things that would compromise our survival such as rotting meat or vomit. Melanie Joy explains that disgust has contamination properties, that’s why when some people (I’m not one of them) find something “disgusting” in their food, like a fly or strand of hair, the meal may be deemed inedible. In the same way, people can be deterred from eating meat when made aware of the animal’s life before it became the meat on their plate.

I remember my friend Ella telling me a story of a girl she knows that used to cherp like a chicken every time a roast chicken was put on the table for her and her family. I found that once I was out of the carnistic schema of thinking, all meat and dairy products evoke a disgust response. However, this phenomena is hard to translate to those who still think within the carnistic schema, who don’t yet see these products as disgusting. Although I am often surprised by meat-eaters understanding of contamination, in knowing that I would not want to have my food prepared in the blood or fat of theirs – even my sisters boyfriend, a butcher by trade, had a good understanding of this without any explanation from me.

Social Psychology

There are various phenomena studied in social psychology that are able to be applied to understand our relationship with non-human animals. Prejudice and discrimination are constructs studies within social psychology. Prejudice is an unjustified or incorrect attitude towards an individual or group based solely on their membership in a group, which historically has included gender, race, sexual orientation and social class. We know of people to discriminate overtly or covertly against an individual and we name this sexism, racism, hetrosexualism and ageism etc.

There is a new kid on the block: speciesism. Speciesism is a form of prejudice pertaining to the assumption of human superiority, leading to the exploitation of animals. Therefore, eating animal products is participating in discrimination against nonhuman animals.

But why might even progressive people, passionate about social justice issues participate in this form of discrimination?

Defence Mechanisms

Sigmond Freud was the first to describe what is known even in popular culture as defence mechanisms, which operate at an unconscious level and enable the individual to escape unpleasant feelings. There are numerous defence mechanisms that have been well documented, perhaps the most commonly known is denial, which just so happens to be the primary defence of carnism. If we deny there is a problem in the first place, we don’t have to do anything about it. Denial is expressed largely through invisibility and the main way carnism remains invisible is by remaining unnamed and unquestioned. The indivisibility of this ideology extends to the trillions of farmed animals who remain out of sight until they’re on a plate; the damage to the environment; the exploited and often traumatised meatpackers and slaughterhouse workers; and the human consumers who are at increased risk for some of the most serious diseases by eating animals.

Another carnistic defence is justification – we learn to justify eating animals though our belief in the deeply entrenched cultural myths about meat, eggs, and dairy. Melanie Joy theorises the Three Ns of Justification, that is: eating animals is normal, natural, and necessary. These myths have been used to justify other exploitative and prejudiced practices and systems, such as slavery and male dominance.

“Humans are the only animals that have children on purpose, keep in touch (or don’t), care about birthdays, waste and lose time, brush their teeth, feel nostalgia, scrub stains, have religions and political parties and laws, wear keepsakes, apologise years after an offense, whisper, fear themselves, interpret dreams, hide their genitalia, shave, bury time capsules and can choose not to eat something for reasons of conscience. The justifications for eating animals and for not eating them are often identical: we are not them” ― Jonathan Safran Foer, Eating Animals

Stages of Behaviour Change

Unless you’re under 5 years old, it’s likely you were raised by parents who ate meat and therefore, you’ve been living within this carnistic ideology for much of your life. This was certainly the case for me; unfortunately I ate meat and dairy until the age of 20.

If you learn of the harms associated with meat and dairy to our own personal health, the environment or the violence inflicted on animals - you will experience the cognitive dissonance associated with eating meat and diary – only then can you begin a journey of behavioural change.

Prochaska and DiClemente are famous for their stages of behaviour change model, which is depicted below:


I use this model heavily in my line of work but also believe it applies to transitioning to veganism (or any change in ideology for that matter).

  1. Most people are pre-contemplative about becoming vegan, that is, its not even on their radar

  2. Documentaries such as Forks Over Knives, Cowspiracy and Earthlings are so profound they generate cognitive dissonance make us contemplate our behaviour and changes we are willing to make.

  3. Looking up vegan resources and recipe books constitute behaviour that fit within the preparation stage of change.

  4. Cooking vegan meals and ordering vegan menu items constitute action towards a behaviour change.

  5. It is said that it takes around a month to create a new habit, after this, you could be considered to be in the maintenance stage of change or transition to veganism

Even if you go vegan overnight I still consider there to be finite stages in behaviour change, that are rather rapid. Other people go vegan gradually over time – there’s no right or wrong way. But if you’re finding it difficult, there are plenty of resources to assist you. I was totally shocked to learn recently that 1 in around 6 people that go vegan “relapse”. Whilst there are people that say that these people were “never vegan to begin with” I think this statistic is testament to the ferocity of the carnistic ideology.

Melanie Joy is the only academic I know of that has pulled this apart psychologically. Her work is the intersection of two of my passions – psychology and animal rights. I highly recommend her books and articles.

Thanks for reading,

Meg x

References and Resources


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