Is Crohn's disease related to food?

Is Crohn's Disease Related to Food?

Yes, Crohn's disease is definitively related to food in multiple ways: diet plays a role as an environmental risk factor for disease development, certain foods can trigger or worsen symptoms, specific dietary patterns can modify disease activity and inflammation, and diet serves as an effective therapeutic intervention for inducing remission. 1, 2

Food as a Risk Factor for Developing Crohn's Disease

Breastfeeding is associated with a lower risk for diagnosis of IBD during childhood, and a healthy Mediterranean diet rich in fruits and vegetables with decreased intake of ultraprocessed foods has been associated with a lower risk of developing IBD. 1

• Sugar-sweetened beverages have been directly linked to increased etiopathogenic risk and a more severe multiyear clinical course of IBD in prospective cohort studies. 1, 2
• The spread of the "western" diet, high in fat and protein but low in fruits and vegetables, has been proposed as a possible explanation for the increase in IBD incidence globally. 1
• Dietary fiber intake has been associated with a lower risk of developing Crohn's disease (but not ulcerative colitis). 1

Foods That Worsen Crohn's Disease Activity

Patients with Crohn's disease should specifically avoid sugar-sweetened beverages, which have been linked to both disease development and a more severe clinical course. 1, 2

• Red and processed meats may worsen disease activity, though the evidence is stronger for ulcerative colitis than Crohn's disease. 1, 2
• Ultraprocessed foods high in added sugar, salt, and artificial additives should be minimized. 1, 2
• High-fat diets may increase bowel permeability and worsen inflammation through dietary-induced changes in gut microbiota. 1

Foods That Help Crohn's Disease

All patients with Crohn's disease should be advised to follow a Mediterranean diet rich in fresh fruits and vegetables, monounsaturated fats, complex carbohydrates, and lean proteins, while keeping ultraprocessed foods, added sugar, and salt low. 1

• A 2021 study demonstrated that nutritional counseling with adherence to the Mediterranean diet resulted in lower rates of active disease, reduced inflammatory biomarker elevation, and improved quality of life in both Crohn's disease and ulcerative colitis patients after 6 months. 1
• The Mediterranean diet has similar efficacy to the specific carbohydrate diet for adults with mild to moderate Crohn's disease. 1
• Fresh fruits and vegetables (cooked or soft texture if strictures are present), monounsaturated fats like olive oil, complex carbohydrates, and lean proteins including fish, poultry, shellfish, beans, and legumes are recommended. 2, 3

Critical Caveat: Strictures Change Everything

Patients with symptomatic intestinal strictures may not tolerate fibrous, plant-based foods (raw fruits and vegetables) due to their texture and risk of mechanical obstruction. 1

• Dietary fiber is contraindicated in the presence of strictures due to the risk of mechanical obstruction. 4
• An emphasis on careful chewing and cooking, steaming, mashing, or blending fruits and vegetables to a soft, less fibrous consistency allows patients with strictures to incorporate plant-based foods safely. 1, 2, 3
• Raw fruits and vegetables, especially unpeeled apples, lettuce, and fibrous vegetables, should be avoided in their raw form when strictures are present. 2

Diet as Active Therapy for Crohn's Disease

Exclusive enteral nutrition (liquid nutrition formulations) is an effective therapy for induction of clinical remission and endoscopic response in Crohn's disease, with stronger evidence in children than adults, and may be considered as a steroid-sparing bridge therapy. 1

• The Crohn's disease exclusion diet (CDED), a type of partial enteral nutrition therapy, may be an effective therapy for induction of clinical remission and endoscopic response in mild to moderate Crohn's disease of relatively short duration. 1
• Exclusive enteral nutrition may be an effective therapy in malnourished patients before undergoing elective surgery for Crohn's disease to optimize nutritional status and reduce postoperative complications. 1
• Although corticosteroids appear more effective in some meta-analyses, enteral nutrition can be offered as an alternative option to induce disease remission. 4

Mechanism: How Food Influences Crohn's Disease

Recurrence of inflammation after ileal resection is dependent on exposure of the neo-terminal ileum to fecal contents, with inflammation recurring within 8 days of exposure to luminal contents, demonstrating that intestinal contents directly drive inflammation. 1

• Diet can promote intestinal inflammation by dysregulating the immune system, altering intestinal permeability and the mucous layer, and contributing to microbial dysbiosis. 5
• Long-term dietary patterns are associated with specific gut microbiome compositions (enterotypes), which may protect against or promote bowel inflammation. 1
• High-fat diets may alter bile acid composition, allowing for a bloom of sulfate-reducing bacteria that produce potentially mucosal toxic hydrogen sulfide. 1

Common Pitfalls to Avoid

Do not adopt overly restrictive elimination diets, as Crohn's disease patients are already at high risk for malnutrition, and excessive restriction worsens nutritional deficiencies. 2, 3

• Do not follow carnivore or other extreme restrictive diets, as they contradict evidence-based guidelines and eliminate essential nutrients. 2
• There is no consistent evidence supporting the avoidance of gluten in patients with Crohn's disease in the absence of a celiac disease diagnosis or suspected gluten sensitivity. 1
• All patients with complicated IBD, malnutrition, or requiring complex nutrition therapies warrant co-management with a registered dietitian. 2, 3
• Regular and systematic monitoring of nutritional status is an essential component of care, as multiple macro- and micronutrient deficiencies are common in Crohn's disease. 6