Eating Disorders and Irritable Bowel Syndrome (IBS): What’s the Connection?

Written by: Tiluka Bhanderi, RD
Reviewed by: Aoife McMahon, RD

Eating disorders and irritable bowel syndrome (IBS): what’s the connection? Many people who struggle with eating disorders (EDs) or disordered eating patterns also experience uncomfortable digestive symptoms like bloating, constipation, diarrhoea or stomach pain. If this sounds familiar, you’re not alone, there’s a strong connection between our eating behaviours and how our gut feels.

What is an Eating Disorder/Disordered Eating?

Eating disorders are serious mental health conditions that involve distressing thoughts and behaviours around food, weight, shape and body image. These include diagnoses such as anorexia nervosa, bulimia nervosa, and binge eating disorder ¹.

Disordered eating refers to unhealthy food habits like skipping meals, chronic dieting or rigid rules around food that don’t meet full diagnostic criteria but still have a big impact on someone’s physical and emotional wellbeing ².

What is IBS?

Irritable Bowel Syndrome (IBS) is a common gut condition that affects how the bowel works.

Symptoms may include:

• Bloating
• Constipation or diarrhoea
• Abdominal pain or cramping
• Excess wind

IBS doesn’t damage the structure of the gut but it can have a significant impact on daily life. It’s a long term condition and symptoms often come and go throughout life. Triggers can include specific foods, stress and lifestyle choices ³.

Could my eating disorder/disordered eating be causing my IBS symptoms?

Eating disorders and irritable bowel syndrome often go hand in hand, creating a viscous cycle that can be hard to break. Digestive symptoms like bloating, pain or constipation can increase anxiety around food and lead to disordered eating patterns which can in turn, worsen gut issues ⁴. This is why it’s so important to address both together with specialist support.

Restrictive or irregular eating can slow down digestion and affect how the gut is able to function. Not getting enough nourishment can also alter the gut microbiome and cause changes to bowel habits. In some cases, behaviours like laxative use or purging can further disrupt the digestive system and make symptoms more persistent or severe.

Top tips to improve IBS symptoms with an eating disorder

Unlike traditional IBS treatment, which can involve unnecessarily cutting out foods, our approach focuses on helping you nourish your body without fuelling restriction.

Top tips:

1. Increase oats: oats contain soluble fibre which can help with regular bowel movements ⁵.
2. Kiwis for constipation: two green kiwis a day contain fibre and enzymes that help with constipation ⁵.
3. Modify fibre intake: with the help of a Registered Dietitian, finding the right balance of fibre for your symptoms can be helpful ³.  
4. Try whole or ground linseeds (flaxseeds) for constipation: start with 1 tsp per day and gradually increase to 1 tbsp and make sure you have enough fluid ⁶.

For more tip on improving IBS with your diet check out the artciles 5 Best Foods to Eat for Irritable Bowel Syndrome (IBS) and Low FODMAP Milk Alternatives.

How can a Registered Dietitian help me?

At Fresh Approach Nutrition, our specialist dietitians are here to help you. They are trained in both eating disorders and IBS and can give you expert personalised advice about treating each condition without negatively impacting on your ED recovery. Book your free discovery call today to understand how we can help you with your recovery.

References:

1. NICE. What is an eating disorder? [Online]. Available https://www.nice.org.uk/guidance/ng69/ifp/chapter/What-is-an-eating-disorder [Accessed: 16^th May 2025]
2. NICE. When should I suspect an eating disorder? [Online]. Available: https://cks.nice.org.uk/topics/eating-disorders/diagnosis/clinical-features/ [Accessed: 16^th May 2025]
3. NHS. Diet, Lifestyle and Medicines – Irritable bowel syndrome (IBS) [Online]. Available: https://www.nhs.uk/conditions/irritable-bowel-syndrome-ibs/diet-lifestyle-and-medicines/ [Accessed: 16^th May 2025]
4. Hedrick, T. (2022). The overlap between eating disorders and gastrointestinal disorders. Practical Gastroenterology, 32-46. (Nutrition Issues in Gastroenterology, Series #224)
5. Monash. Two kiwi fruit a day to keep constipation at bay! [Online] Available: https://www.monashfodmap.com/blog/two-kiwi-fruit-day-keep-constipation-bay/ [Accessed: 16^th May 2025]
6. BDA. Irritable Bowel Syndrome. [online] Available: https://www.bda.uk.com/resource/irritable-bowel-syndrome-diet.html [Accessed: 16^th May 2025]