When seeing a patient for constipation, what are the first things you consider?

For many of us, the usual factors come to mind: hydration, physical activity, fiber intake, and bathroom habits.

Another important consideration to add to this list: undernutrition, especially when working with IBD patients.

This week, I followed up with two patients with Crohn’s disease who initially sought help for severe constipation and bloating.

In both cases, undernutrition—stemming from a fear of food—was the key driver of their symptoms.

Undernutrition can worsen symptoms of constipation and bloating by…

  • Reducing gastrocolic reflex activity, decreasing the natural urge for bowel movements.
  • Weakening GI muscles, slowing motility.
  • Disrupting the gut microbiome, decreasing diversity and worsening symptoms or inflammation.
  • Leading to carbohydrate malabsorption, causing gas, bloating and other GI symptoms, potentially because of a weakened intestinal mucosal barrier.

These patients were limiting what and how much they ate out of concern certain foods might trigger flares or symptoms.

Fear of food is a common issue for IBD patients, often leading to overly restrictive diets, nutritional deficiencies, avoidance of favorite foods, social challenges, and even ARFID (Avoidant/Restrictive Food Intake Disorder).

While ARFID requires deeper discussion, this post offers 11 actionable tips to help IBD patients improve constipation and bloating by eating more and expanding their diet:

  1. Start with Safe Foods
    Encourage patients to eat more of the foods they feel comfortable with.
  2. Add Nutritional Shakes
    Recommend pre-made or homemade shakes to boost calories and nutrients to ensure nutritional adequacy, essential for optimal GI functioning.
  3. Introduce New Foods Gradually
    Help identify foods they’re open to trying. Begin with small portions, reassuring them that small amounts are unlikely to cause significant symptoms or inflammation.
  4. Set a Meal Schedule
    Create a structured eating plan with regular meal and snack times.
  5. Supplement When Necessary
    Consider a multivitamin to fill in nutritional gaps and/or magnesium and fiber supplements to address constipation.
  6. Build on Their Comfort Zone
    For example, if rolled oats are safe, explore variations like overnight oats, oatmeal cookies, savory oats, or granola.
  7. Hydration is Key
    Remind patients to prioritize hydration for GI motility and overall health. I find it’s best to set a specific daily hydration goal.
  8. Consider Fiber Type and Tolerance
    Gradually add fiber from soft vegetables or fruits, starting with low-fructan options to reduce gas and bloating.
  9. Encourage Stress Management and Movement
    Recommend gentle activities like walking and yoga to support motility.
  10. Check In Frequently
    Regular follow-ups offer guidance and reassurance. During food reintroductions, I often provide encouragement, again emphasizing that small, gradual changes are unlikely to cause significant problems.
  11. Refer to a GI Psychologist
    Specialists can help patients address food fears and safely reintroduce foods.

By helping patients understand how their fear of food and dietary restrictions impact their symptoms and overall GI health—and by offering practical tips like these—we can gradually guide them toward a more balanced diet, breaking the cycle and building their confidence to eat.