The Invisible Link Between Autism and Eating Disorders
Updated: Jan 10
In 1983, Swedish psychologist proposed the link between autism and anorexia nervosa. This came from his observation of 3 autistic boys whose female cousins all had anorexia and whilst he initially suggested that anorexia was the 'female version of autism' (obviously not entirely true), this proposal lead to further investigations by other psychologists and psychiatrists. Despite a lack of extensive research into this area, it is widely accepted that people who are autistic are more likely to have anorexia, or other eating disorders. Here's what we know so far.
Autism, Food and Eating
It is common for autistic people to have atypical behaviours regarding food and eating, with approximately 70% of people reporting struggles when it comes to food. This could be due to a number of different factors; individuals may be highly selective when it comes to what foods they want to eat or be very sensitive to different textures, tastes and smells.
In my own classes, I have had a number of children who will only eat one particular thing. I've had kids who will only eat crackers, custard creams, pureed baby food or plain chips. I feel the below graphic shows a potential reason as to why children like very particular foods, or even very particular brands. A fundamental trait of autism is a liking of things that are predictable and the same, and many foods can taste different depending on when they are season, how they are cooked and how ripe they are. Things like crackers, biscuits etc will taste the same every time and are therefore predictable.
The social aspects of eating can also be challenging. Think about how many social elements there are to sitting down to eat a meal - sitting at the table with others, using a knife and fork correctly, engaging in conversation, waiting for others when you've finished...All of these things could cause an autistic person great anxiety and stress, so some may avoid this situation entirely.
There may also be physical difficulties with food as it has been shown that there is a link between autism and gastrointestinal difficulties. Eating food, or at least certain foods, may actually cause physical pain and discomfort and so any food that doesn't cause pain will be favoured.
Autism & Anorexia Nervosa
The potential link between autism and anorexia nervosa was first proposed in the early 1980's by Swedish psychologist Christopher Gillberg. It was observed that girls with anorexia and/or autism displayed greater inflexibility, social difficulties, lower empathy and a greater tendency to systemise (create and follow rules) than other people. Other similarities observed in those with autism and/or anorexia is a strong interest in details and systems, a tendency to focus on themselves and inflexible behaviours and attitudes.
Anorexia nervosa is a mental health disorder and eating disorder where people who have anorexia try to keep their weight as low as possible by not eating enough food or exercising too much, or both. They often have a distorted image of their bodies, thinking they're fat even when they're underweight. Men and women of any age can get anorexia, but it's most common in young women and typically starts in the mid-teens.
It has been shown that between 20-35% of women and girls with anorexia also fit the diagnostic criteria for autism. Many other women and girls with anorexia also exhibit higher levels of symptoms characteristic of autism than the general population without actually meeting the threshold for a diagnosis.
Autism & Avoidant/Restrictive Food Intake Disorder (ARFID)
Avoidant/Restrictive Food Intake Disorder (ARFID) is defined by the DSM-5 as an eating or feeding disorder characterised by a persistent and disturbed pattern of feeding or eating that leads to a failure to meet nutritional/energy needs.
ARFID is similar to anorexia insofar as there is a restriction of food intake but the reasoning behind the restriction is different. People with ARFID do not restrict food intake to avoid weight gain or to control their body shape. As mentioned above, people with autism can struggle with various textures, tastes and smells of food which can lead to a restriction in what is deemed 'acceptable' foods, so therefore they would meet some criteria for ARFID. Although there is no concrete data on the link between autism and ARFID, it is thought there is a strong correlation.
Things to Keep in Mind Regarding Food & Autism
Autistic people can be very sensitive to sounds, touches, smells, tastes and sights. When it comes to meal times, be conscious of these sensory difficulties to try and make the event as sensory friendly as possible. Some things to consider are the food choice, the level of noise in the environment (chatter, knives and forks on plates, wrappers, sound of others eating), the smells of other food etc.
For children who don't like food touching each other (due to mix in textures and tastes), try divided plates where you can easily separate foods.
Routine, rituals and resistance
People with autism have a strong preference for routine, structure and ensuring that things are predictable. Should routines change suddenly, this can cause a great deal of distress so where things can be kept the same and structured, they should be. Keeping meal times to the same time, eating in the same locations and having a meal plan could be great ways to keep structure and predictability when it comes to food.
Visual timetables also work incredibly well and you can use them both at home and school.
Interoception refers to a difficulty in recognising and responding to the body's internal states and systems. Some autistic people can struggle in recognising when they are hungry or thirsty, whereas others can struggle to recognise when they are full. Both can lead to health complications such as being undernourished or overweight.
“I’m not very good at judging my own emotions or physical sensations. I don’t really fully understand my thirst and hunger responses, or my fullness responses, so that really influences my eating because I can binge or miss meals very, very easily.”
Alexithymia refers to a difficulty in identifying and describing emotions and is common in autism. People with alexithymia may have a hard time pinpointing what emotion they are feeling and also not be able to communicate what they are feeling to others. This can make it hard for people to soothe themselves or get support from others and can make them more vulnerable to developing eating disorder symptoms as a coping mechanism.
Treatment of Eating Disorders in Autistic People
Sadly, autistic people with an eating disorder like ARFID or anorexia typically have worse outcomes than their non-autistic peers. This may be due to traditional treatment methods not being accommodating of their autistic needs and focusing too heavily on correcting body image perception and body weight.
Therapy for eating disorders often involves in-person doctor’s appointments and inpatient stays. People in treatment often need to eat meals in group settings, which can be noisy and overwhelming, making eating even more difficult. Many autistic people have trouble visiting doctor’s offices because of sensory sensitivities, such as an aversion to bright fluorescent lights. Group therapy may also be difficult for some autistic people. It’s important for clinicians treating eating disorders to be aware of the overlap, experts say, as many of the people they treat may have undetected autism.