Eating Disorder Comorbidities: The Conditions That Co-Occur, and Why It Matters

Eating disorders often occur alongside other mental health conditions. Anxiety, depression, obsessive-compulsive disorder (OCD), trauma-related difficulties and neurodivergence are all commonly seen in people with eating disorders.

Having more than one diagnosis can feel overwhelming, but it is also very common. These difficulties are often connected rather than entirely separate, which is why specialist treatment should look at the whole picture rather than focusing only on eating behaviours.

In summary: Eating disorder comorbidities are other mental health conditions that occur alongside an eating disorder. Common examples include anxiety, depression, OCD, trauma-related conditions and substance misuse. Because these difficulties can interact and reinforce one another, treatment is usually most effective when it is coordinated within one overall plan.

What are eating disorder comorbidities?

A comorbidity simply means that two or more health conditions occur at the same time.

For example, somebody may have anorexia nervosa alongside OCD, or bulimia nervosa alongside depression or anxiety.

Sometimes one condition clearly comes first. Anxiety, for example, often predates an eating disorder, while depression can emerge as the eating disorder becomes more severe. In other cases, the relationship is less clear and the difficulties develop together.

What matters most is understanding how the different problems interact and what may be maintaining them now.

You can read more about the conditions that commonly co-occur with eating disorders.

What are the most common eating disorder comorbidities?

Some of the most frequently seen comorbidities include:

Anxiety disorders. Anxiety is very common alongside eating disorders and may begin before the eating disorder itself. Perfectionism, fear of making mistakes and difficulty tolerating uncertainty can all become tied into food rules, checking, avoidance and exercise. Read more about eating disorders and anxiety.

Depression. Low mood may precede an eating disorder or develop as a consequence of it. Social isolation, low energy, reduced concentration and the narrowing of everyday life around food and weight can all contribute. Find out more about eating disorders and depression.

Obsessive-compulsive disorder. OCD is particularly strongly associated with anorexia nervosa. The two conditions can share features such as rigidity, rituals, perfectionism and intolerance of uncertainty. However, similar-looking behaviours may have different causes, so understanding the purpose of a ritual or avoidance behaviour is important. Read more about OCD and eating disorders treatment.

Trauma and PTSD. For some people, eating-disorder behaviours can become a way of coping with overwhelming emotions, feeling safer or creating predictability. Where trauma and an eating disorder coexist, treatment may need careful pacing and coordination. Read more about PTSD, trauma and eating disorders.

Substance misuse. Alcohol or substance misuse can also occur alongside eating disorders, particularly where impulsivity or difficulties regulating emotions are present. Both need to be considered as part of the wider treatment plan.

Why do eating disorders and other conditions occur together?

Several different diagnoses can sometimes reflect shared underlying difficulties rather than completely unrelated problems.

Eating disorders, anxiety and OCD, for example, can all involve perfectionism, repetitive thinking, fear and difficulty tolerating uncertainty.

Eating-disorder behaviours may also temporarily reduce distress. Restricting, binge eating, purging or compulsive exercise can provide short-term relief from difficult emotions or anxiety, which can reinforce the behaviour and make it harder to change.

A good assessment therefore asks not only which diagnoses are present? but also how are these difficulties connected?

That understanding helps guide treatment.

Eating disorders, neurodivergence, OCD and ARFID

Autism and ADHD can affect how eating difficulties develop and present. Sensory sensitivities, executive-functioning difficulties, interoceptive differences and a need for predictability can all influence eating.

You can read more about support for neurodivergent people with eating disorders.

ARFID can also overlap with OCD. For example, somebody with ARFID may avoid food because of sensory sensitivities, fear of choking or vomiting, or low interest in eating. Someone with OCD may restrict food because of intrusive fears around contamination or harm. Sometimes both are present.

Treatment needs to identify what is driving the restriction. It may include nutritional rehabilitation, adapted cognitive behavioural approaches, exposure work or exposure and response prevention for OCD symptoms, alongside adaptations for neurodivergence where needed.

At The London Centre, our ARFID specialists can work alongside clinicians experienced in OCD and neurodivergence as part of a coordinated plan.

Why integrated treatment matters

Treating an eating disorder without considering significant anxiety, OCD, depression or trauma can make recovery harder. Equally, focusing on another mental health condition while overlooking the eating disorder may miss an important part of the problem.

Integrated treatment does not necessarily mean that every condition must be treated intensively at exactly the same time. The right approach depends on the severity and complexity of each difficulty, physical health, risk and the person’s preferences.

The key is coordination.

At The London Centre for Eating Disorders and Body Image, psychologists, dietitians and psychiatrists can work together within one multidisciplinary treatment plan. This may include psychological therapy, dietetic support, eating disorder psychiatry for comorbid conditions or more intensive multidisciplinary care where needed.

Treatment can take place in person or through eating disorder online therapy in the UK where remote care is clinically appropriate.

Our outpatient model means that people can work on recovery while remaining within everyday life, relationships, work or education.

Finding help when more than one difficulty is present

You do not need to work out which diagnosis is the “main” problem before seeking help.

A specialist eating-disorder assessment should consider eating behaviours, physical health, mood, anxiety, obsessive-compulsive symptoms, trauma, neurodivergence and any other relevant difficulties together.

At The London Centre, our aim is to understand how those difficulties fit together and create one individualised, coordinated treatment plan rather than treating a collection of separate labels.

Contact The London Centre to discuss an assessment for yourself or someone you care about.

Frequently asked questions

Which comes first, the eating disorder or the comorbidity?

It varies. Anxiety often begins before an eating disorder, while depression may develop as an eating disorder progresses. More important than establishing which came first is understanding how the two difficulties interact now.

Can treating the eating disorder improve the other condition?

Sometimes. Improved nutrition and reduced eating-disorder behaviours can benefit mood, concentration and psychological flexibility. However, significant co-occurring conditions should still be assessed and treated directly where needed.

Should comorbid conditions be treated at the same time or one after another?

There is no single approach that suits everyone. Treatment may take place simultaneously or in stages depending on the individual, but it should form part of one coordinated plan.

What mental health conditions commonly occur alongside anorexia nervosa?

Anxiety disorders, depression and OCD are particularly common alongside anorexia nervosa. Trauma-related difficulties, self-harm and substance misuse may also be relevant for some people.

Who treats eating disorders alongside other mental health conditions?

Specialist multidisciplinary eating-disorder services are best placed to assess the whole picture. At The London Centre, psychologists, dietitians and psychiatrists can work together to address both the eating disorder and relevant co-occurring difficulties.