Nutritional management of adults with inflammatory bowel disease: practical lessons from the available evidence

Inflammatory bowel disease (IBD) is associated with impairment of nutritional status both anthropometrically and biochemically, which results from both qualitative and quantitative changes in dietary intake alongside disease activity. Dietary intervention to replace deficiency is essential and may also be used to treat active disease and to reduce symptoms. The evidence for dietary interventions in this area is reviewed and the following recommendations made: Assessment of nutritional status is an essential part of the investigation of all patients with IBD and deficiency should be actively sought. Any patient with macro-or micronutrient deficiency should be referred for dietetic assessment. Micronutrient deficiency (most frequently iron, vitamin B-12, folate and magnesium) should be replaced aggressively, parenterally if necessary. Significant improvement in gastrointestinal symptoms can be achieved by low-residue diets (for stricturing disease) and (always under dietetic supervision) management of lactose and other intolerances. Irritable bowel syndrome symptoms in patients with IBD can respond to low fermentable oligo-, di-, monosaccharide and polyol (FODMAP) diets, again this must be done under dietetic supervision. Active Crohn's disease can be treated by exclusive enteral nutrition (elemental/polymeric/altered fat formulations all have equivalent efficacy). Enteral nutrition can maintain remission in Crohn's disease and in this context can be given alongside normal oral intake. Nutritional support does not have an established role in the treatment of active ulcerative colitis, other than in the management of malnutrition. Total parenteral nutrition should not be used unless intestinal failure occurs. There is insufficient evidence to support the routine use of Omega 3 fish oil, prebiotics and glutamine in the treatment of active IBD.