Dietary therapies for inflammatory bowel disease

Abstract

Inflammatory bowel disease (IBD) is chronic relapsing and remitting inflammatory condition of the gastrointestinal tract. In a genetically susceptible host, environmental factors may trigger dysregulation of the immune response and lead to the development of chronic inflammation. Epidemiological studies suggest that environmental factors may be responsible for the recent increase in the worldwide incidence of IBD. The gut microbiota and dietary intake are the two largest environmental exposures for the gastrointestinal tract. Multiple studies have suggested that the microbiota is involved in the pathogenesis of IBD, but dietary intake has been shown to change the composition and function of the microbiota, suggesting that it, too, may be a potential therapeutic target in IBD. The typical westernized diet, containing high amounts of animal fat, refined sugars, and processed foods with limited fresh fruits, vegetables, and fiber, seems to be associated with an increased risk of IBD. In this chapter, we summarize epidemiological data supporting the role of diet in IBD, show that the composition of the gut microbiota is heavily influenced by diet, and describe the relationship between macronutrients, food additives, oral supplements, and IBD. We consider how dietary therapy can be used to contribute to the effectiveness of medications in managing IBD. We also review the literature regarding several structured diets proposed to treat IBD including exclusive and partial enteral nutrition, specific carbohydrate diet, IBD anti-inflammatory diet, low-FODMAP diet, CD-TREAT, and the Crohn disease exclusion diet (CDED).