Understanding the Relationship Between OCD and Eating Disorders

Many people experiencing an eating disorder describe intrusive thoughts, repeated behaviours or rituals, and significant anxiety, characteristics which could also be attributed to OCD. For some people, a thorough assessment may help to differentiate the two conditions, but for others, it may be that they’re experiencing both.

Research suggests around 1 in 5 people with an eating disorder will also experience OCD at some point in their lives. Understanding the relationship between these conditions can explain why recovery sometimes feels so challenging, and why treating both matters.

What is OCD?

Everyone experiences intrusive thoughts from time to time. For people with OCD, these thoughts can become highly distressing and hard to dismiss.

Many people with OCD experience something called thought-action fusion. This is the belief that having an unwanted thought makes something more likely to happen, or that the thought reveals something important about who they are. This escalates intrusive thoughts from merely unwanted, to genuinely distressing.

Common obsession themes can include:

• contamination
• checking
• harm, including fear of causing accidents (such as “hit and run” fears)
• magical thinking
• needing things to feel “just right”

To manage the anxiety these thoughts create, people with OCD develop compulsions, which are behaviours or mental acts performed to reduce anxiety or prevent a feared outcome. Examples of these may include:

• reassurance seeking
• checking, or
• silently repeating words or phrases

Can OCD and Eating Disorders overlap?

For some people, eating disorder behaviours develop as part of their OCD presentation. For others, OCD can make eating disorder recovery more difficult by reinforcing rules, rituals or anxiety around food, body image or eating.

Eating disorders also often involve routines and rituals around food. The key difference? Eating disorders typically have core concerns about weight, shape, or control, whereas OCD related eating behaviours are usually motivated by intrusive fears (such as contamination concerns).

For example, someone with OCD may avoid a food because they fear contamination, and someone with an eating disorder may avoid the same food because of fears about weight gain. And sometimes, both concerns are present at the same time.

OCD and eating disorders are distinct conditions, but they share some common ground. Both may:

• Develop or intensify during periods of stress, anxiety or trauma
• Be a way of coping with uncertainty or emotional distress
• Involve perfectionism, a need for certainty or attempts to regain a sense of control
• Be associated with high personal standards and self-criticism

Despite these similarities, the thoughts and beliefs driving each condition can differ.

OCD, Autism or both?

It’s also important to recognise that some common autistic traits such as routines, repetitive behaviours or sensory preferences, can appear very similar to compulsions. While similar, the reasons behind them are often very different.

For many autistic people, routines and sensory preferences can be meaningful, comforting and regulating. It’s also possible to be autistic and experience OCD or an eating disorder, which is why it’s important to understand the purpose or function of a behaviour, to consider the needs it may be meeting or purpose it may be serving, as opposed to merely trying to alter or stop the behaviour.

How does OCD affect Eating Disorder recovery?

While these conditions can co-occur, treating one does not automatically lead to recovery from the other. When both are present, an integrated approach to treatment, which understands both the cause and the functions of behaviours is usually most effective.

One of the recommended psychological treatments for OCD is Exposure and Response Prevention (ERP). ERP can be incorporated alongside evidence-based eating disorder treatment when appropriate, and it involves gradually facing situations which trigger obsessive fears, while resisting the urge to perform compulsions. While compulsions can bring short-term relief from anxiety in OCD, over time they unintentionally reinforce OCD.

With the support of a psychologist experienced in ERP, people can learn to trust that anxiety can naturally rise and fall, without needing to perform compulsions, and that the feared outcomes are far less likely, or more manageable, than OCD predicts.

ERP gradually loosens the beliefs that maintain OCD. Many people become more confident, flexible and better able to manage anxiety. Good ERP is collaborative, compassionate and tailored to each persons pace. The work can be challenging, but an appropriately trained Psychologist can support you in this process.

How do I know if I have OCD, an Eating Disorder, or both?

Only a qualified mental health clinician can make a differential diagnosis between these similar (and often overlapping) conditions. Signs that both may be present include combinations of:

• Ongoing, unwanted intrusive thoughts that lead to repetitive rituals
• Eating rules that don’t fully fit typical eating disorder patterns, such as rules about preventing food contamination
• Feeling unable to stop rituals, even when you recognise they don’t make sense

Plenty of people experience obsessive thoughts or perfectionistic tendencies without meeting the criteria for OCD, so individualised assessment is valuable.

When to seek help

If obsessive thoughts, rituals or eating behaviours are getting in the way of your daily life, relationships or wellbeing, it’s time to reach out for help.

Living with OCD, an eating disorder or both can feel overwhelming. But effective treatment is available. With the right assessment and evidence-based care, people can reduce anxiety, regain flexibility, and build a kinder, more flexible relationship with food, their thoughts and themselves.

Mind Body Well Psychologist Stacey Van der Meer works with people experiencing OCD and eating disorders, and provides ERP-informed treatment. Sessions are available both in person at our South Melbourne office, and online via telehealth.