Disordered Eating in Irritable Bowel Syndrome

Did you know that people with IBS are at higher risk of developing disordered eating? While we don’t know the cause of this relationship, a number of factors may play a role. For example:

• Depression, anxiety and stress are more common among people with IBS, and these conditions can increase the risk of disordered eating(1).
• People can become fearful of experiencing GI symptoms, and in turn worry that particular foods trigger GI symptoms. These fears can fuel dietary restrictions to manage food and symptom-related fears, such as not eating unfamiliar foods, refusing foods prepared by others or avoiding meals outside the home(2).
• Finally, the restrictive diets used to manage IBS (e.g. the FODMAP diet) can cause people to:
  • Fixate on food choices and the impact of these on symptoms
  • Constantly monitor and record food intake
  • Lose weight unintentionally
  • Develop black-and-white thinking about certain foods, e.g., categorising them as ‘good’ or ‘bad’, and actively avoiding ‘bad’ foods for fear of symptoms
  • Avoid eating out and social occasions around food for fear of eating trigger foods(3)

So, while diet therapies can be very effective in managing GI symptoms in some, they do carry risks, and both patients and clinicians should consider strategies to mitigate these risks.

Below are some tips for patients and clinicians to reduce the risks of the FODMAP diet.

Tips for patients -

1. Work with a dietitian - Dietitians can help to design you a minimally restrictive diet for the short and long term.
2. Remember, it's temporary – The low FODMAP diet is intended as a short-term tool to identify triggers, not a long-term way of eating.
3. Focus on what you can eat – Instead of dwelling on restrictions, explore delicious, low FODMAP recipes
4. Don't aim for perfection – Aim to reduce your FODMAP intake, but don't worry about eating small amounts of FODMAPs. They are actually good for your gut!
5. Make sure you eat enough food – Prepare balanced meals that include a mix of high fibre, low FODMAP carbohydrates, lean proteins and healthy fats.
6. Remember to reintroduce – The goal is to expand your diet in the long term, not stay restricted forever.
7. Watch out for food-related fears – If you start focusing excessively on foods, or avoiding foods unnecessarily, talk to your dietitian.
8. Keep meal times enjoyable – Eat with friends and family. Don't let the diet isolate you.
9. Be mindful of weight loss – If you notice unintentional weight loss, seek support from health professionals.
10. It’s not all about food – Remember, other lifestyle factors such as stress and sleep also affect IBS symptoms.

Tips for dietitians -

1. Consider if the patient is suitable for a FODMAP diet - Screen for disordered eating using tools such as the SCOFF or nine-item ARFID screen(2). While these tools are not validated among people with IBS, they are currently the best we have. However, you can ask questions beyond these screeners based on your clinical judgment. If you are not certain refer on to a health professional who conducts comprehensive eating disorder assessments.
2. Consider non-restrictive or less-restrictive dietary approaches. Examples include the ‘FODMAP Gentle’ approach, manipulating fibre intake or including kiwifruit(4)
3. Frame the diet flexibly – Avoid strict rules and emphasise personal tolerance.
4. Set clear timeframes and book follow-up appointments - make it clear from the start that the FODMAP diet is followed in 3 steps, and that Step 1 should only be followed by 2–6 weeks, followed by reintroduction and personalisation
5. Encourage food variety and nutritional adequacy – Ensure the diet is nutritionally balanced to prevent deficiencies.
6. Consider non-dietary approaches – consider referral for gut-directed hypnotherapy, stress management or cognitive behaviour therapy
7. Refer on - If you suspect disordered eating, with the patient’s permission refer them back to their medical practitioner for:
   - a formal diagnosis
   - medical risk management
   - referral on for mental health and allied health intervention.

References

1. Satherley R, Howard R, Higgs S. Disordered eating practices in gastrointestinal disorders. Appetite. 2015;84:240-50.
2. Whelan K, Ford AC, Burton-Murray H, Staudacher HM. Dietary management of irritable bowel syndrome: considerations, challenges, and solutions. The Lancet Gastroenterology & Hepatology. 2024;9(12):1147-61.
3. Riehl ME, Scarlata K. Understanding Disordered Eating Risks in Patients with Gastrointestinal Conditions. J Acad Nutr Diet. 2021.
4. O'Brien L, Kasti A, Halmos EP, Tuck C, Varney J. Evolution, adaptation, and new applications of the FODMAP diet. JGH Open. 2024;8(5):e13066.