Beyond Food, Why Eating Disorders Are Deeply Complex
When we look at an eating disorder from the outside, food is often the most visible part.
Someone stops eating certain foods. They begin restricting. They binge. They purge. They become preoccupied with calories, weight, exercise, ingredients, or their body.
Naturally, we start to think that food is the problem.
But food is often only the place where the problem has become visible.
Eating disorders are complex psychiatric illnesses. They are not simply caused by dieting, wanting to be thin, social media, poor body image, or a lack of nutrition education. Current research points toward an interaction between genetics, biology, psychology, environment, relationships, stress, and social influences.
Two people can grow up in the same culture, see the same advertisements, experience the same diet trends and even follow the same diet.
One may walk away relatively unaffected.
The other may develop an eating disorder.
Some people may be biologically more vulnerable
One of the most important shifts in how we understand eating disorders is recognizing that they have a significant biological component.
You don't inherit an eating disorder in the same simple way you might inherit eye colour. Instead, you can inherit traits and biological vulnerabilities that make an eating disorder more likely to develop under certain circumstances.
Twin research, for example, estimates heritability at approximately 28–74% for anorexia nervosa, 55–62% for bulimia nervosa and 39–45% for binge-eating disorder, although estimates vary between studies and populations.
Research into anorexia nervosa has also identified genetic relationships not only with psychiatric traits but with metabolic characteristics, challenging the outdated idea that anorexia is purely psychological or simply a fear of gaining weight.
This means someone may enter the world with a nervous system, temperament or biology that makes them more susceptible.
Traits frequently associated with eating-disorder vulnerability can include things such as anxiety, perfectionism, rigidity, obsessive-compulsive tendencies, heightened sensitivity to threat or punishment, and differences in how reward and internal bodily signals are processed.
None of these traits means someone will develop an eating disorder.
Think of genetics as loading the gun, while life experiences and environment can sometimes pull the trigger.
The brain matters too
Eating disorders involve the brain including systems responsible for reward, motivation, emotion, appetite, body awareness and threat detection.
Neurobiological research has identified differences across brain networks involved in these processes, although scientists are still working to determine which differences represent pre-existing vulnerability and which develop or intensify as a consequence of the eating disorder itself.
This distinction is important.
Malnutrition itself changes the brain.
When the brain is inadequately nourished, thinking can become increasingly rigid. Anxiety can increase. Obsessive thoughts about food may intensify. Decision-making can become more difficult.
And this can create a vicious cycle:
Restriction → malnutrition → increased rigidity and food preoccupation → greater fear and anxiety → further restriction.
At that point, asking someone to simply "make a better choice" dramatically underestimates what is happening biologically.
Then comes the environment
Biology doesn't exist in isolation.
We grow up inside families, friendships, schools, sports, communities and cultures — and all of those environments teach us something about food, bodies and worth.
A child might hear:
"Are you really going to eat that?"
"Carbs make you fat."
"I was so bad today. I ate dessert."
"You look amazing, have you lost weight?"
Perhaps a parent is constantly dieting. A coach emphasizes weight. Friends begin comparing bodies. Someone is bullied for their appearance. Social media repeatedly presents thinness as health, discipline or desirability.
Research has found associations between eating-disorder risk and experiences including appearance-related teasing, parental comments about weight and eating, adverse childhood experiences and trauma. Importantly, these are risk factors, not simple causes and blaming families is neither accurate nor helpful.
Sometimes there is no obvious environmental trigger at all.
That does not make the illness any less real.
Sometimes the eating disorder becomes a coping mechanism
This is the piece I think we need to talk about much more.
For some people, an eating disorder begins to do something for them psychologically.
Restriction may temporarily create a sense of control when everything else feels chaotic.
Binge eating may temporarily numb overwhelming emotion.
Purging may temporarily provide relief from distress.
Compulsive exercise may become a way of managing anxiety.
Rules around food may create predictability when life feels unpredictable.
Focusing intensely on calories, weight or food may even provide somewhere for the brain to direct emotions that feel much harder to understand.
That doesn't mean the person chose an eating disorder.
It means the behaviour may have become reinforced because, at some point, it served a function.
Research increasingly recognizes emotion regulation, stress and trauma as important pieces of eating-disorder vulnerability and maintenance. A 2025 comprehensive review, for example, found higher rates of several forms of trauma among people with eating disorders, particularly in binge-purge presentations.
And this helps explain why simply removing the behaviour isn't always enough.
If we take away someone's coping mechanism without helping them understand what it was helping them cope with, we haven't addressed the whole illness.
Starvation can eventually maintain the disorder
Another important distinction is that what starts an eating disorder isn't necessarily what keeps it going.
Maybe it began with dieting, bullying or it could have emerged during an intensely stressful period.
Maybe food became the one thing someone felt able to control.
But eventually, restriction and malnutrition themselves can perpetuate psychological and biological changes that make recovery increasingly difficult.
Likewise, binge-purge cycles can become deeply reinforced patterns involving distress, temporary relief, guilt and renewed attempts at restriction.
The eating disorder begins building its own feedback loops.
This is one reason early intervention matters.
This is why recovery has to involve more than a meal plan
Nutrition rehabilitation is essential.
The brain and body need adequate energy to recover, and nutritional restoration can be lifesaving.
But recovery cannot always stop at "eat more."
We may also need to understand:
What purpose has the eating disorder been serving?
What happens emotionally when the behaviors are challenged?
Is anxiety driving the need for control?
Is perfectionism involved?
How much of someone's identity or self-worth has become attached to their body?
What beliefs about food were learned growing up?
Are trauma, bullying, loss or chronic stress part of the picture?
What happens when this person feels overwhelmed?
What healthier coping strategies can eventually replace the eating-disorder behaviors?
This is why effective eating-disorder treatment is often multidisciplinary, involving medical monitoring, nutritional rehabilitation and psychological treatment rather than expecting one practitioner or one intervention to address every component.
