Eating Disorders and Autism: What You Need to Know

Note: In this blog, we use identity-first language (e.g., “an autistic individual”) to reflect those who embrace autism as an identity category – a diverse way of perceiving and interacting with the world (Taboas et al., 2022; Bury et al., 2020). However, we recognize that this language choice may not be suitable for everyone in the community. Whenever possible, please ask individuals about the language appropriate for them.

Living with and treating an eating disorder may be complicated by the presence of a co-occurring condition, particularly when the condition shares characteristics with an eating disorder. One such condition that shares some psychopathology with a disordered eating mindset—and is frequently seen alongside an eating disorder diagnosis—is autism spectrum disorder.

There are a number of factors that increase the risk of disordered eating or an eating disorder in an autistic individual. By looking at the nature of both eating disorders and autism spectrum disorders, we can better understand their relationship and improve the detection, care, and treatment of both conditions.

What is Autism?

Autism, or autism spectrum disorder, refers to a broad range of neurodevelopmental conditions characterized by challenges in social skills, interpersonal communication, and restricted or repetitive behaviors or interests. It’s important to note that autism doesn’t have “one” look. Autism is considered a spectrum disorder, meaning that there are many types and variances in how it presents from person to person.

An autism diagnosis can generally be made around 18–24 months of age, when characteristics can be distinguished from those typical in early development. That said, signs of autism may not be noticed or identified until an individual is much older.

There are many limitations in pinpointing the global prevalence of autism, such as a lack of public awareness, an evolving clinical definition of autism, shortcomings in public health responses, and underdiagnosed populations such as adults, marginalized groups, and those who identify as girls or women. Experts estimate that for every three cases of autism spectrum disorder, there are two additional undiagnosed cases (Fusar-Poli et al., 2020). Recent studies suggest the median prevalence of autism is one in every 100 individuals worldwide (Zeidan et al., 2022).

There is no medical test used to diagnose autism. Rather, a diagnosis is given after observing symptoms and assessing the severity of behaviors. Some of the more common symptoms of autism include:

• Difficulty interpreting others’ body language, facial expressions, and social cues
• Narrow or intense interest in certain topics
• Difficulty speaking, making eye contact, and/or appropriately managing tone of voice
• Repetitive or ritualistic behaviors
• Trouble managing and regulating emotions
• Feeling overwhelmed in social situations
• Difficulty maintaining a conversation and understanding conversational give-and-take
• Need for routines and resistance to change
• Sensory issues, involving either heightened or under-sensitivity to sounds, smells, light, touch, pain, and other stimuli

The Overlap of Autism and Eating Disorders

The relationship between autism and eating disorders is not well known, but it is surprisingly common. We see higher rates of autism—and autism characteristics—in people who have eating disorders. There is a crossover in the underlying neurological underpinnings of eating disorders and autism spectrum disorders. Like eating disorders, autism spectrum disorders are biological, brain-based conditions. Autistic individuals and people with eating disorders share a number of traits, most notably:

• Inflexible thinking
• Sensory processing issues
• Repetitive behaviors
• Insistence on routines

While we don’t know the precise scope of the intersection between eating disorders and autism, we do know that autism is more prevalent in eating disorder populations than in the general population. It is estimated that 20–30% of adults and 3–10% of young people with eating disorders also have an autism diagnosis (Solmi et al., 2020).

Traits of Autism That May Increase Eating Disorder Risk

Despite the high rates of autism in eating disorder populations, autism does not definitively predate someone to an eating disorder. That said, there are certain characteristics that may precipitate disordered eating habits or the development of an eating disorder in those already susceptible.

Sensory processing challenges

One eating-related issue common in autism are sensory processing challenges. This is a characteristic that is often present but not required for an autism diagnosis. Sensory processing challenges include both over-reactivity (a heightened sensitivity to sensory inputs from the environment, such as sounds feeling extremely loud or lights seeming too bright), or under-reactivity (an inadequate reaction to sensory input, such as not noticing that a fire alarm has gone off).

For individuals on the spectrum who have this heightened sensitivity, the texture of foods can be especially significant. A person with heightened sensitivity to the texture of foods might complain that the food they’re consuming is too mushy or too wet, too crunchy or too dry. This sensitivity can have a profound impact on an individual’s food choices, leading them to be very selective about what they will consume on a regular basis. They might be highly attuned to differences among brands of the same food or the cooking style and day-to-day preparation of the food.

This sensitivity to food can lead to a very narrow nutrition profile—one limited to “safe” foods with repetitive flavors and textures. In reducing the range of what is okay to eat, an individual with heightened sensitivity may become undernourished, making it harder for the brain to work effectively and clearly. People who struggle to meet their nutritional needs from food as a result of sensory qualities typically meet the criteria for Avoidant/Restrictive Food Intake Disorder (ARFID).

On the flip side, other autistic individuals may struggle with eating because they don’t have a good sense of when they’re hungry or full; they lack interoception, or awareness of what’s happening in their body. People who struggle to be aware of what their body needs may go through spurts of overeating, undereating, or a mixture of both.

Intense interest

Another characteristic common in many autistic individuals is the tendency to dive intensely into an interest. Rather than being interested in a wide variety of things on a surface level, many individuals tend to have one or two areas of all-consuming interest. Autistic individuals who exhibit this pattern may find themselves narrowing in on an obsessive interest in food or weight. Some will be intensely interested in nutrition or physical activity.

Sometimes this focus will turn inwards to a fixation on a particular body type. In pursuit of this interest, an individual may begin tracking their measurements or calorie counting, which are warning signs of anorexia nervosa. It is very likely that an individual with this intense interest and approach may have a limited range of nutrition or very strict, inflexible rules around eating. This puts them at a heightened risk of developing a full-blown eating disorder.

When this narrowed interest in nutrition and the body intersects with a strong desire for things to stay the same (another hallmark trait present in autism spectrum disorders), an individual may struggle deeply with natural fluctuations in weight or shape, particularly during puberty or pregnancy. This may contribute to an all-consuming focus on nutrition intake and body size or shape to ensure their weight is consistent. This inflexible thinking puts an individual at risk of disordered eating or exercise behaviors that do not support their wellbeing.

Ritualism and avoidance to change

It is common for autistic people to have a ritualistic approach to eating. The term “food jag” is frequently used in the autism community, and refers to a tendency to eat the same foods, prepared the same way, every day, and sometimes every meal. These restrictive eating patterns are often displayed in children and may continue into adulthood.

Autistic people may struggle with cognitive flexibility, which can lead to dichotomous thinking about food. Autistic individuals might display a rigid desire for control that manifests in the form of a very limited nutritional palette composed entirely of “safe” foods. This predetermined inflexible eating path could trigger or intensify an eating disorder.

Treating Eating Disorders in Autistic People

The presence of autism spectrum disorder has the potential to complicate a client’s illness, as well as their eating disorder recovery. Research shows that autistic adults tend to experience longer-lasting and more severe eating disorders (Tchanturia et al., 2019). The good news is that autism does not make eating disorder recovery impossible—or even less likely (Nielsen et al., 2015).

The key to achieving full recovery—which is, and has been proven to be, completely possible for autistic people—is comprehensive, individualized treatment that prioritizes the needs of the autistic individual with an eating disorder. Providers must keep the potential presence of sensory issues, intense interests, cognitive inflexibility, and interoception at the forefront of assessment, diagnosis, and treatment. It is essential that eating disorder treatment for an autistic individual is inclusive, enabling, and affirming. Because autism is a spectrum disorder, a treatment plan should ultimately honor and reflect the unique needs of the client.

The Emily Program takes a personalized approach to eating disorder treatment and recovery. Please give us a call at 866-502-4606 or click here to learn more about the individualized care we offer.

Founded in 1993, The Emily Program is nationally recognized for our compassionate and personalized approach to eating disorder awareness, treatment, and lifetime recovery. We understand the tangled complexities of eating disorders, often from personal experiences. We know that you’re not defined by your eating disorder, and our team of experts—including therapists, dietitians, and medical staff—focuses on treating the whole person. We provide an integrative approach for people of all ages and genders who struggle with eating disorders and related mental health and body image issues. The Emily Program care teams bring decades of experience managing the unique medical and psychiatric complications of eating disorders. With convenient locations in MN, OH, PA, and WA or within a virtual environment, The Emily Program is here to help you no matter where you live. For more information, please visit emilyprogram.com.