What dietary recommendations should be given to a patient with Crohn disease?

Dietary Management of Crohn's Disease

Primary Recommendation

All patients with Crohn's disease should follow a Mediterranean diet rich in fresh fruits and vegetables, monounsaturated fats, complex carbohydrates, and lean proteins, while minimizing ultraprocessed foods, added sugar, and salt. 1 This recommendation applies unless contraindications exist, and serves as the foundational dietary approach for overall health and disease management.

General Dietary Framework

Foods to Emphasize

• Fresh fruits and vegetables prepared appropriately for tolerance 1
• Monounsaturated fats (olive oil, avocados) 1
• Complex carbohydrates (whole grains when tolerated) 1
• Lean proteins (fish, chicken, eggs) 1
• Soluble fiber rather than insoluble roughage 2

Foods to Minimize or Avoid

• Sugar-sweetened beverages are strongly linked to worse disease course and should be avoided 1, 2
• Red and processed meats may worsen disease activity, though evidence is stronger for ulcerative colitis 1, 2
• Ultraprocessed foods high in added sugar, salt, and artificial additives 1, 2
• Gluten avoidance is not necessary unless celiac disease or documented gluten sensitivity exists 1, 2

Critical Modification: Patients with Strictures

Patients with symptomatic intestinal strictures require texture-modified diets to prevent obstruction. 1, 2 This is a common pitfall—fibrous, plant-based foods become problematic only in the presence of strictures, not in remission without strictures.

Safe Food Preparation for Strictures

• Cook, steam, mash, or blend fruits and vegetables to soft consistency 1, 2
• Careful chewing of all foods 1
• Think applesauce (safe) versus unpeeled apple (obstruction risk) 1
• Patients in remission without strictures do not need fiber restriction 1

Diet as Active Therapy (Not Just Symptom Management)

Exclusive Enteral Nutrition (EEN)

EEN is an effective steroid-sparing therapy for inducing clinical and endoscopic remission in Crohn's disease, with 60-80% remission rates. 1, 2 This involves 100% of calories from liquid formulations for 6-8 weeks.

• Stronger evidence in children than adults due to compliance challenges 1, 2
• Standard polymeric formulations (Ensure Plus, Kate Farms, Jevity) are equally effective—no specific product superiority 1
• May be used preoperatively in malnourished patients to optimize surgical outcomes 1
• Not effective for ulcerative colitis 1

Crohn's Disease Exclusion Diet (CDED)

CDED may induce remission in mild to moderate Crohn's disease of short duration. 1, 2 This is a partial enteral nutrition approach that allows some solid foods, potentially improving compliance over EEN.

Three-phase approach over 18 weeks: 1

• Phase 1 (weeks 1-6): Mandatory fish, chicken breast, eggs; allowed rice, cooled potatoes, specific vegetables/fruits in limited quantities; partial liquid formula supplementation
• Phase 2 (weeks 7-12): Add tuna, whole-grain bread, oats, yams, red peppers, reintroduce certain vegetables/beans after week 10
• Phase 3 (maintenance): Expand to more seafood, eggs, grains, some dairy, alcohol if tolerated

Common Pitfalls to Avoid

Overly Restrictive Elimination Diets

Do not adopt unnecessarily restrictive diets—Crohn's patients are already at high malnutrition risk. 2 While avoiding symptom triggers makes sense acutely, maintaining these restrictions during remission leads to nutritional deficiencies and unnecessary dietary fear.

Misunderstanding Fiber

Fiber is not universally harmful in Crohn's disease. 1, 2 The texture and preparation matter more than fiber content itself. Soluble fiber and well-cooked vegetables are beneficial in remission without strictures.

Lactose Restriction Without Testing

Only restrict dairy if lactose intolerance is documented 3—not all Crohn's patients are lactose intolerant, and unnecessary restriction eliminates important calcium and vitamin D sources.

When to Use Parenteral Nutrition

Parenteral nutrition is reserved for specific scenarios, not routine Crohn's management: 1

• Intestinal failure or short bowel syndrome
• Severe malnutrition with inability to tolerate oral/enteral intake
• Prolonged ileus post-surgery
• High-output fistulas
• Intra-abdominal abscesses requiring bowel rest

Parenteral nutrition offers no advantage over enteral nutrition for disease control when the gut can be used 4

Practical Implementation Algorithm

1. Start with Mediterranean diet framework for all patients 1
2. Assess for strictures—if present, modify texture of plant-based foods 1, 2
3. Eliminate sugar-sweetened beverages universally 1, 2
4. For active disease requiring remission induction:
   • Consider EEN (especially pediatrics or steroid-sparing need) 1, 2
   • Consider CDED for mild-moderate disease of short duration 1, 2
5. Screen for and correct nutritional deficiencies (vitamin D, B12, iron, zinc) 3
6. Avoid unnecessary restrictions during remission 2