Understanding the Link Between Eating Disorders, Autism & ADHD

By Jamie Manwaring, PhD

Neurodevelopmental disorders like autism and ADHD can be linked to eating disorders due to sensory issues, impulsivity and rigid thinking. These traits can lead to restrictive eating, binge eating and challenges with food variety and mealtime behaviors. Tailored therapies like exposure therapy and cognitive remediation help build flexible eating habits and improve coping skills.

Eating Disorders & Co-occurring Neurodevelopmental Disorders

Research shows that up to 95% of people diagnosed with an eating disorder also have at least one other co-occurring psychiatric disorder (dual diagnosis).1 Some patients with eating disorders also have a co-occurring neurodevelopmental disorder, such as attention deficit hyperactivity disorder (ADHD) or autism spectrum disorder (ASD).

Neurodevelopmental Disorders

Neurodevelopmental disorders are a category of psychiatric conditions that impact nervous system development. Some neurodevelopmental disorders, such as ADHD and ASD, are more common in people with eating disorders.1

Neurodevelopmental disorders impact key areas of life, including:

  • Social interactions
  • Communication
  • Learning
  • Motor skills
  • Emotional regulation

Attention deficit hyperactivity disorder

ADHD is a persistent pattern of inattention and/or hyperactivity and impulsivity that disrupts functioning and development. It is characterized by symptoms of inattention and/or hyperactivity that are not appropriate. Some common symptoms include:2

  • Trouble paying attention
  • Interrupting or intruding on others
  • Difficulty organizing tasks and activities
  • Fidgeting with items, tapping hands or feet or squirming in seat
  • Avoidance of tasks that require mental effort over a long period of time
  • Is often “on the go”

There are three presentations of ADHD that can occur:2

  • Combined inattentive and hyperactive-impulsive presentation
  • Predominantly inattentive presentation
  • Predominantly hyperactive-impulsive presentation

ADHD & eating disorders

Children with ADHD are more likely to develop an eating disorder than their peers. The prevalence of ADHD symptoms among people with eating disorders ranges from 5-17%, and the rate of eating disorders in those with ADHD can be as high as 12%.3

Children with ADHD face a higher risk of bulimia nervosa symptoms. Girls with ADHD are more than three times as likely to have an eating disorder compared to their peers.4 Girls with ADHD are 3.6 times more likely to have any eating disorder than girls without ADHD, and they are 5.6 times more likely to specifically have bulimia nervosa.3

While ADHD is more commonly linked to binge eating, it can also occur in restrictive eating disorders. In one study, the prevalence of ADHD symptoms was as high as 18% among those with the anorexia nervosa restricting subtype (AN-R).5

Shared traits of bulimia & ADHD

Impulsivity and inattention are common features of both bulimia nervosa and ADHD, with research indicating that ADHD occurs more frequently in patients with bulimia nervosa.3

Those with ADHD often show poor impulse control and emotional dysregulation,6 which are also common in individuals with bulimia nervosa and binge eating disorder, potentially contributing to binge eating.

ADHD & eating disorder treatment outcomes

ADHD also indirectly impacts patient outcomes. Those with ADHD tend to have more severe eating disorder symptoms, which are associated with poorer clinical outcomes.7,8 This may be because impulsivity can lead to treatment dropout.

Autism spectrum disorder

ASD is characterized by persistent deficits in social communication and interactions, restricted interests and repetitive behaviors. Those with autism present with a combination of:2

  • Deficits in social-emotional reciprocity
  • Deficits in nonverbal communicative behaviors
  • Deficits in developing, maintaining and understanding relationships

Repetitive and recurring behaviors are common in those with ASD, such as:2

  • Stereotyped speech, repetitive motor movements, echolalia or repetitive use of objects or abnormal phrases
  • Rigid adherence to routines and ritualized patterns
  • Highly restricted interests with abnormal intensity or focus
  • Increased or decreased reactivity to sensory input or unusual interest in sensory aspects of the environment

ASD & eating disorders

Research indicates a higher prevalence of ASD among patients with eating disorders. Nearly 23% of individuals with ASD have an eating disorder, compared to 2% of the general population.9

Shared traits of ASD & anorexia

Anorexia nervosa and ASD share some symptomology, including:10

  • Reduced ability to experience pleasure (social anhedonia)
  • Deficits in emotional intelligence
  • Difficulty on advanced theory of mind tests (which measure the ability to understand and infer complex mental states)
  • Rigidity on tests of set-shifting (which measure cognitive flexibility)
  • Excellent performance on tests of attention to detail
  • Impaired ability to be aware of, identify and describe one's feelings (and alexithymia)

Restricted and intense focus on specific interests can be limited to or directed toward food, and diet, with rigid attitudes manifesting through weight-focused repetitive behaviors like body checks or weigh-ins.

Shared traits of ASD & avoidant/restrictive food intake disorder

Individuals with ASD and avoidant/restrictive food intake disorder (ARFID) also share similar symptoms. Food selectivity is a common eating issue among children with ASD.

Having aversions to different aspects of foods or rigid brand preference can cause those with ASD to become underweight. Individuals, both children and adults, with ASD who have increased reactivity to sensory input may avoid certain foods based on smell, texture, appearance, temperature or color.

Hyperfixation & Eating Disorders

People with ADHD can hyperfixate on specific subjects or activities, focusing intensely for a long time, or show all-or-nothing thinking patterns. Their eating disorder manifests through a hyperfixation on calorie restriction, nutrition, fad dieting or exercise.

Individuals with autism may also hyperfocus on specific topics or behaviors, such as fad diets, calorie restriction, nutrition or exercise. Women and girls with autism might also restrict their food intake to gain social acceptance by conforming to the thin ideal.

Is Picky Eating an Eating Disorder?

Picky eating may or may not be an eating disorder, depending on its severity. It’s common for people to have food preferences, but it’s rare for it to develop into an eating disorder like ARFID. The difference is that ARFID can lead to malnutrition, medical complications and, in children, stunted growth.

Effective Therapies for Autism, ADHD & Eating disorders

Limited research exists on the most effective ways to treat individuals with neurodevelopmental and eating disorders. Patients with these co-occurring conditions may benefit more from one-on-one sessions rather than group therapy, with recent focus on customizing ED treatments specifically for those with ASD.

Exposure & response prevention

Exposure and response prevention (ERP) is a behavioral therapy that gradually exposes people to situations designed to provoke a patient’s trigger in a safe environment.

Patients gradually face situations, foods and thoughts that trigger anxiety and challenge themselves not to perform compulsive behaviors in response. ERP can be especially helpful for patients with autism and ARFID who have fear-based reactions to certain foods.

Cognitive remediation therapy

Cognitive remediation therapy (CRT) is a behavioral intervention aimed at addressing cognitive problems to enhance daily functioning. For individuals with eating disorders and a neurodevelopmental disorder, this may involve improving cognitive flexibility and central coherence, although it is less studied compared to other eating disorder therapies.

Find Help for Dual Diagnosis

Living with both an eating disorder and a neurodevelopmental disorder can feel especially overwhelming, but you don’t have to navigate it alone. Integrated care that addresses both conditions at the same time is essential for lasting recovery. With the right support team and evidence-based treatment, recovery is possible.

References

  1. Hambleton, A., Pepin, G., Le, A., Maloney, D., Aouad, P., Barakat, S., Boakes, R. A., Brennan, L., Bryant, E., Byrne, S. M., Caldwell, B., Calvert, S., Carroll, B., Castle, D. J., Caterson, I. D., Chelius, B., Chiem, L., Clarke, S., Conti, J., . . . Maguire, S. (2022). Psychiatric and medical comorbidities of eating disorders: findings from a rapid review of the literature. Journal of Eating Disorders, 10(1). https://doi.org/10.1186/s40337-022-00654-2
  2. American Psychiatric Association. (2013). Diagnostic and Statistical Manual of Mental Disorders (5th ed.). Arlington, VA.
  3. Reinblatt, S. P. (2015). Are Eating Disorders Related to Attention Deficit/Hyperactivity Disorder? Current Treatment Options in Psychiatry, 2(4), 402–412. https://doi.org/10.1007/s40501-015-0060-7
  4. Biederman, J., Ball, S., Monuteaux, M. C., Surman, C. B. H., Johnson, J. S., & Zeitlin, S. (2007). Are Girls with ADHD at Risk for Eating Disorders? Results from a Controlled, Five-Year Prospective Study. Journal of Developmental and Behavioral Pediatrics, 28(4), 302–307. https://doi.org/10.1097/dbp.0b013e3180327917
  5. Yao, S., Kuja-Halkola, R., Martin, J., Lu, Y., Lichtenstein, P., Norring, C., Birgegård, A., Yilmaz, Z., Hübel, C., Watson, H., Baker, J., Almqvist, C., Thornton, L. M., Magnusson, P. K., Bulik, C. M., Larsson, H., Adan, R., Ando, T., Baker, J., . . . Bulik, C. (2019). Associations between Attention-Deficit/Hyperactivity Disorder and various Eating Disorders: A Swedish nationwide population study using multiple genetically informative approaches. Biological Psychiatry, 86(8), 577–586. https://doi.org/10.1016/j.biopsych.2019.04.036
  6. Archi, S. E., Cortese, S., Ballon, N., Réveillère, C., De Luca, A., Barrault, S., & Brunault, P. (2020). Negative Affectivity and Emotion Dysregulation as Mediators between ADHD and Disordered Eating: A Systematic Review. Nutrients, 12(11), 3292. https://doi.org/10.3390/nu12113292
  7. Testa, G., Baenas, I., Vintró-Alcaraz, C., Granero, R., Agüera, Z., Sánchez, I., Riesco, N., Jiménez-Murcia, S., & Fernández-Aranda, F. (2020). Does ADHD Symptomatology Influence Treatment Outcome and Dropout Risk in Eating Disorders? A longitudinal Study. Journal of Clinical Medicine, 9(7), 2305. https://doi.org/10.3390/jcm9072305
  8. Svedlund, N. E., Norring, C., Ginsberg, Y., & Von Hausswolff‐Juhlin, Y. (2018). Are treatment results for eating disorders affected by ADHD symptoms? A one‐year follow‐up of adult females. European Eating Disorders Review, 26(4), 337–345. https://doi.org/10.1002/erv.2598
  9. Huke, V., Turk, J., Saeidi, S., Kent, A., & Morgan, J. (2013). Autism Spectrum Disorders in Eating Disorder Populations: A Systematic Review. European Eating Disorders Review, 21(5), 345–351. https://doi.org/10.1002/erv.2244
  10. Pini, S., Abelli, M., Carpita, B., Dell’Osso, L., Castellini, G., Carmassi, C., & Ricca, V. (2016). Historical evolution of the concept of anorexia nervosa and relationships with orthorexia nervosa, autism, and obsessive-compulsive spectrum. Neuropsychiatric Disease and Treatment, Volume 12, 1651–1660. https://doi.org/10.2147/ndt.s108912

ACUTE Earns Prestigious Center of Excellence Designation from Anthem
In 2018, the ACUTE Center for Eating Disorders & Severe Malnutrition at Denver Health was honored by Anthem Health as a Center of Excellence for Medical Treatment of Severe and Extreme Eating Disorders. ACUTE is the first medical unit ever to achieve this designation in the field of eating disorders. It comes after a rigorous review process.

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