MENTAL HEALTH
The Autism-Anorexia Connection
The gender diagnosis gap matters
When I was training to be a registered dietitian, I counselled patients with anorexia nervosa. I had never been diagnosed with the condition myself, but I was no stranger to body dysmorphia and restrictive eating practices. Like most young women, I grew up immersed in diet culture.
And like many others, I aspired to contort my body into the unnatural shapes presented by airbrushed magazine covers. I experimented with vegetarianism, calorie-counting and compulsive exercise.
My calorie and exercise goals were frequently unhealthy. Throughout my teenage years and into adulthood, my weight ricocheted left and right. At my thinnest, I was marginally underweight and at my largest, marginally overweight.
Anorexia nervosa, however, is more complicated than simply being the most extreme form of dieting. While restrictive food practices leading to becoming underweight are at the heart of the condition, the factors that precipitate these are complex.
The disorder is not always triggered by body dysmorphia (preoccupation and distress about some feature of the body), though it is characterized by it.
Certain personality traits make an individual more likely to exhibit the behaviours that lead to a diagnosis of anorexia nervosa. These include high harm avoidance, low novelty seeking and in restrictive types, persistence.
There have been studies suggesting that high harm avoidance and low novelty-seeking may be correlated with autism as well. High levels of persistence in self-injurious behaviour also may be prevalent among autistic people.
In 1982, Dr. Christopher Gillberg, a professor of adolescent and child psychology, observed that several male autistic patients had female cousins with anorexia nervosa and that the propensity towards sameness was present in both autism and anorexia. He further postulated that there may be a biological link between the two and went so far as to propose that anorexia nervosa may be a female presentation of autism.
There is, in fact, an astoundingly high correlation between autism and anorexia nervosa.
On a Danish nationwide cohort study examining all individuals born from 1981 to 2008, individuals first diagnosed as autistic had a 5x greater risk of being diagnosed subsequently with anorexia nervosa. Likewise, those first diagnosed with anorexia nervosa had a 15x subsequent risk of being diagnosed as autistic.
One study estimates that over 20% of patients with eating disorders that persist long term are autistic. Another study suggests that over 50% of anorexia nervosa patients may present with high levels of autistic traits.
The causal link to this correlation is difficult to parse out. It may be linked to differences in hunger and satiety cues, sensory processing differences, the tendency to develop strict rules and routines, special interests around calorie counting etc. Alexithymia, or difficulty identifying and describing one’s own emotional experience, may also play a role.
Autism is also associated with worse outcomes for patients with eating disorders, including resistance to treatment long-term.
Autistic individuals with anorexia nervosa and other eating disorders have reported that their autism is linked with their eating disorders. Fixed routines, rituals around food and inflexibility associated with being autistic were important contributors to their eating disorders.
Autistic eating disorder patients also reported that desire for weight loss and low self-esteem were less important in the development of their eating disorder overall than the need for control, executive function difficulties around food preparation and acquisition, social issues and sensory differences.
Current research suggests that targeting autism-specific modulators of anorexia in treatment may help improve recovery rates. These include isolation and relational/social difficulties. Some recovery centres focus on group therapy and mealtime, which may hinder recovery for autistic patients. Focus on dramatic changes in eating and routines may also be inappropriate for autistic patients.
An autistic diagnosis is important for autistic patients with anorexia nervosa or other eating disorders. It allows for better-tailored treatment plans and a focus on the correct underlying roots of the eating disorder. However, despite females making up three-quarters of anorexia nervosa cases, many autistic females remain undiagnosed, misdiagnosed or wait until later in life for their diagnosis.
Anorexia nervosa can be life or death, and when girls and women lack the full understanding of factors influencing their condition, they are at a disadvantage for recovery. For this reason, it is essential to narrow the diagnosis gap between boys/men and girls/women.
I identify as neurodivergent — diagnosed with ADHD, definite autistic traits and possibly autistic. I don’t think I would easily be diagnosed as autistic though due to gender bias in the diagnostic criteria.
Looking back, the times I was underweight, and the time I was a vegetarian were times I experienced enormous sensory difficulties around food. They were also fairly chaotic times in my life, full of what felt like big changes at the time — changes that were out of my control.
I was ashamed of how small my body was and hid it under large clothes. I was in my early twenties, and it had never even occurred to me that I might be neurodivergent.
It is not hard for me to imagine how other neurodivergent individuals develop eating disorders first precipitated by sensory sensitivities and the need to maintain a sense of order and control.
It is also not hard to imagine how lack of self-understanding would make it more difficult to prevent and treat. If you don’t realize the reasons for a behaviour, it is harder to stop.
Autistic people deserve neurotype-specific care and prevention. Understanding the link between anorexia nervosa and autism can help clinicians, families and individuals watch for warning signs and seek help earlier.
Focus on food variety may be detrimental to many autistic individuals at risk for eating disorders. Their food preferences and needs for same-foods may be valid eating strategies.
Clinicians and researchers would do well to work alongside the autistic community to find ways to prevent and treat autistic individuals with anorexia nervosa and other eating disorders.
Julia Marsiglio is a Canadian author who writes poetry, fiction, and non-fiction exploring topics such as trauma, grief, mental health, marginalization, and neurodivergence. Find me on Twitter, Instagram and Facebook, or buy me a coffee! You may also enjoy: