The information in this article originally appeared in an Equip Academy presentation. Watch the presentation here, and register for future Equip Academy events to learn about other eating disorder-related topics and earn free CE credits.

There is significant overlap between autism and eating disorders. In this article, I’ll describe the common presentations of co-occurring eating disorders and autism, explore treatment outcomes for patients with autism and eating disorders, and discuss ways in which evidence-based interventions can be adapted for the treatment of these two conditions.

What is autism? Defining the terms

First, let’s define some of the terms we’ll be using here and what we mean by them. When we speak of autism, we’re referring to a specific expression of neurodivergence, while acknowledging that many other neurodivergences exist and may be impactful to eating disorder treatment. The neurodivergent umbrella also encompasses:

• Attention deficit hyperactivity disorder (ADHD)
• Obsessive-compulsive disorder (OCD)
• Dyslexia
• Epilepsy
• Misophonia
• Tic disorders
• Post-traumatic stress disorder (PTSD)
• Bipolar disorder
• …and many others

Like other aspects of neurodivergence, autism is defined by differences in the way in which people learn, communicate, interact, and behave. Autism presents in many different ways, and is generally characterized by:

• Challenges communicating with others or understanding how others feel
• Specific or narrow areas of interest
• Engaging in repetitive movements or behaviors

However, it’s important to keep in mind the principle that if you know one person with autism, you know one person with autism. The spectrum is vast and diverse, and while we will discuss specific concerns and strategies today, we want to remind everyone that it will be critical to adapt these strategies to fit the unique and specific needs of each individual.

We will also be aiming to use identify-first language (i.e., “autistic person” rather than “a person with autism”), as that is the preference for most people in the autism community. However, this preference is not universal and we may, at times, slip into person-first language. It is always important to ask someone what their language preferences are with respect to autism and to not make assumptions. The perspective reflected here is informed by research, clinical training, and from our colleagues and clients with lived experience of autism.

The overlap between autism and eating disorders

The overlap of autism and eating disorders is much higher than previously thought. Research shows that 37% of people with anorexia nervosa have autism, and that 55% of people with ARFID have autism and other developmental conditions. While there are fewer studies, an overlap exists between autism and bulimia nervosa and binge eating disorder, too.

Case examples

Consider these two case examples to understand some of the different ways that co-occurring autism and eating disorders might present:

Grace: autism and anorexia

Grace was a young teenage girl diagnosed with autism. She had an intense interest in and passion for animals. A video at school on the meat industry led her to become a vegetarian. This focus then turned to “healthy eating.” Grace later said that the desire to eat healthy became one of the extreme areas of focus for her autism. She controlled all of her meals at home, sometimes having intense outbursts if her mother stepped in to get her to eat more. She struggled to eat with others, particularly her brother who she said was “gross” at mealtimes.

Andrew: autism and ARFID

Andrew was an elementary school-aged boy who had always preferred a small number of foods. He lived in a large city and had specific street vendors or small shops that served the foods he preferred most. Each day, his mother would go out and purchase all the foods he needed for each meal. Attempts to swap frozen or homemade versions resulted in tears and refusal to eat. His growth was poor and the family felt very stuck and isolated. Andrew’s clinicians wondered if Andrew might have autism.

Similarities between autism and eating disorders

The overlap between autism and eating disorders can be better understood by looking at some of the similarities between the two conditions.

Cognitive processing styles

Both people with autism and people with eating disorders, particularly anorexia and ARFID, may struggle with areas of executive functioning, such as difficulty set shifting and more rigid thinking styles. Black-and-white thinking and preference for routine are also common.

Differences in social and emotional communication

Difficulty identifying and understanding other people’s emotions, trouble interpreting facial expressions, and a lower tendency to study facial features are all traits that appear to link autism and anorexia.

Sensory sensitivities

Differences in sensory processing are common among people with autism, and also drive one of the three main presentations of ARFID: food avoidance due to sensory sensitivity. Hypo- and hyper-sensitivity can apply to food, noise, light, clothing, and more.

Challenges to treatment for co-occurring autism and eating disorders

Research shows that patients with co-occurring autism and eating disorders face a number of barriers to treatment, and may have a more difficult time achieving recovery.

Late diagnosis

Many women diagnosed with autism and eating disorders received their eating disorder diagnosis first. Autism often goes undiagnosed in women because they learn to mask (suppress autistic behaviors in an attempt to “fit in”).

Lack of training

Many eating disorder clinicians report a lack of training or familiarity with autism. Therefore, clinicians have also expressed a lack of confidence in working with autistic patients.

Greater treatment utilization

In general, research is mixed regarding the impact of autistic traits on eating disorder treatment outcomes. However, autistic patients do have longer hospital stays and spend more days in PHP/IOP treatment settings.

Adapting treatment for autistic patients

There have been a number of studies and research initiatives that provide guidance on treating autistic patients with eating disorders. The accommodations we’ll review in this article have been drawn from our own clinical experiences as well as the following studies and resources:

The PEACE Pathway

This resource includes recommendations for specialist inpatient and day programs that involve staff training, changes to the clinic environment, and use of special menus.

Loomes and Bryant-Waugh

These researchers have provided detailed descriptions of how family-based treatment (FBT) could be adapted to meet the needs of autistic patients with anorexia.

Field, Fox, Jones & Williams

These researchers conducted a Delphi study that brought together expertise from clinicians, researchers, and lived experience to generate consensus statements on the needs and service recommendations for autism and anorexia.

There are distinct aspects of autism that can impact eating behaviors and should be considered in treatment. The five that we’ll focus on here are:

• Sensory processing
• Executive functioning
• Communication
• Behaviors
• Demand avoidance

Sensory processing

Many people with autism experience an increased or decreased reactivity to sensory input. Sensory processing may influence eating and feeding from a biopsychosocial perspective, and can have a wide impact on eating, including food aversions, insistence on sameness, social eating, hunger and satiety cues, body image, and intuitive eating. Given all this, it may be necessary to adapt environment and meal plans to accommodate the sensory needs of autistic patients.

Eating and feeding behaviors impacted by sensory processing issues for autistic individuals can be categorized into three main areas: exteroception, interoception, and proprioception.

Exteroception

Exteroception is the process of perceiving the external environment through the senses (vision, hearing, touch, smell, and taste). When possible, providers can accommodate exteroceptive preferences related to both the environment and food in order to help reduce overall anxiety.

• Environmental accommodations: Minimizing sensory triggers or distractions by dimming bright lights, creating a quiet environment, or allowing for noise-cancelling headphones, for example.
• Food-related accommodations: Adjusting the temperature and texture of foods, and incorporating the use of appropriate distractions during mealtimes, like music, fidgets, etc.

Interoception

Interoception is the ability to sense and be aware of internal bodily sensations, such as heart rate, hunger, fullness, thirst, temperature, pain, etc. When possible, providers should work with individuals to identify how their interoceptive awareness interacts with their feeding and adapt treatment goals and strategies based on individual needs.

Is the individual you’re working with able to feel the sensation of hunger, fullness, and thirst? How do they experience and communicate temperature, pain, etc.?

Proprioception

Proprioception is the perception or awareness of the position and movement of the body.

People with autism may experience atypical proprioception, and they may prefer to move or position their bodies differently when eating (for example, eating while standing or walking, eating while lying down, etc.).

When possible and appropriate, providers should allow individuals to eat in positions that fit their needs and are comfortable for them to facilitate a positive eating experience.

Executive functioning

People with autism may have difficulty with executive functioning. This can create challenges with working memory, cognitive flexibility, and inhibition control (self-regulation), which could result in issues around managing everyday tasks like planning, problem-solving, and adjusting to new situations.

Adding tools, such as visual cues and communication systems, can help support executive functioning needs during treatment. Some strategies and examples to consider:

• Create predictable routines and meal plans. This can help people on the autism spectrum prepare for and manage stress and anxiety while they adapt to changes, expectations, and switching tasks at mealtimes.
• Use visual systems. For many people with autism, visualizing their way through a specific task or process can be incredibly helpful. For instance, visualizing the steps involved in making a meal (gathering all of your ingredients and utensils, breaking down each step of the instructions, etc.).
• Adapt systems and tools based on each individual’s preferences and needs (visual versus verbal, specific challenges, etc).

Communication

Many people on the autism spectrum experience difficulties with communication, including auditory processing speed differences. Communication is a key aspect of interpersonal relationships, connection, and self-advocacy, so it is essential to support and accommodate this need when working with individuals on the spectrum. Providers should take care to use alternative language tools and options to support communication with patients who have co-occurring autism and eating disorders.

Some strategies and considerations to keep in mind:

• Be patient and allow extra time for responses. Avoid rushing or adding pressure to communicate, especially at meal times.
• Bolster the ease of communication by stating clear and reasonable plans, goals, and expectations ahead of time
• Add visual communication aids, such as visual schedules, timers, etc.
• Use different communication tools and options such as AACs (Augmentative and Alternative Communication systems) and/or sign language to support communication.
• Literal thinking can influence eating-related behaviors for individuals on the spectrum. Diet culture and health messaging may be interpreted as rules that must be followed, and it can be difficult for them to separate from them (e.g., food morality: “good” versus “bad” foods).

Behaviors

In treating patients who have co-occurring autism and eating disorders, it can be helpful to understand how different behaviors may be used as coping mechanisms. The strategies below can help you address unwanted behaviors appropriately in autistic patients:

• When addressing behaviors, concentrate on the eating behavior goal, not the individual’s disruptive or distracting behaviors.
• Establish a routine and make meals predictable, which will help increase feelings of control and decrease feelings of uncertainty and disruption.
• Model appropriate behavior during food exposure. Use yourself as a model to demonstrate eating new foods, trying something different, using coping skills at mealtime, etc.
• Non-injurious stimming (self-stimulatory) behaviors—like hand flapping, fidgeting, rocking, clapping, and repeating words or sounds (echolalia or palilalia)—can be very important communicative, self-regulating, and self-soothing mechanisms for neurodivergent people. Don’t judge or stop these behaviors, as they may be a way for the individual to cope and work through a difficult meal exposure.
• Be mindful of social factors. People on the spectrum may prefer to eat alone, as social interactions and settings can contribute to sensory triggers and interrupt the focus and coping skills that are necessary for meal completion.
• Continue to build coping skills that can help with regulation.
• If a behavior is concerning and dangerous, consult with an autism professional to make a plan that supports the individual’s needs and health.

Demand avoidance

Individuals with demand avoidance may avoid or refuse certain tasks or activities that create discomfort or dysregulation with sensory overwhelm. Mealtimes often involve many demands—explicit and implicit—that set expectations, and this can become overwhelming and unbearable for some people on the spectrum.

To avoid struggles around demands, you can employ a few strategies:

• Offer choices
• Use indirect phrasing instead of direct demands
• Encourage autonomy

Working together with patients

When treating patients who have co-occurring autism and eating disorders, it’s essential to work collaboratively together. Be creative, flexible, and focused.

Work with the co-occurring diagnosis: invite autism into the room! Talk about their diagnosis from the beginning. This will create an environment where you can work together to identify accommodations. If you suspect a patient has autism but they haven’t yet been diagnosed, refer them out for an evaluation. You’ll both gain valuable information.

Some strategies to create a collaborative, effective relationship with your autistic patients:

• Create a plan together by listening to the individual’s needs.
• As you listen to the individual’s needs, respect autonomy, promote self-efficacy, and encourage flexibility.
• Provide education, options, and rationale for accommodations and adaptations to help validate the individuals’ experience and create an environment of collaboration, trust, and autonomy.
• Ask the individual what their specific sensory triggers are (smells, sounds, colors, lights, textures, etc.).
• Work with the individual to make a list of accommodations that can help (eating alone vs. group, dimmed lights, quiet environment with access to headphones, etc.).
• Create a clear Cope Ahead plan that establishes what warning signs they show/feel/experience when feeling overwhelmed and/or overstimulated, and what coping skills they can use in that moment to help. Make sure this plan is visible at mealtimes as a reminder.
• Collaborate with other professionals, family members, and support systems to ensure all their needs are taken into consideration, and that follow-through and meal plans can be supported by all. This might include a registered dietitian for nutritional needs/deficiencies; speech pathologist for oral-motor difficulties, etc; occupational therapist for daily living skills; clinical neuropsychologist for diagnosing and treatment planning recommendations; psychiatrist for medications; RN/medical provider for medical support; therapist for mental health and eating disorder support.

For more information on the intersection between autism and eating disorders and how to treat both, watch my recorded Equip Academy presentation on the topic. You can also explore past Equip Academy presentations and register for upcoming events here.