The role of nutritional intervention in inflammatory bowel disease (IBD) is twofold: first, as primary therapy for patients with acute Crohn's disease; second, as an invaluable adjunctive therapy for the correction and maintenance of nutritional status for both patients with Crohn's disease and those with ulcerative colitis. Careful nutritional monitoring and appropriate nutritional intervention throughout all stages of disease should be an integral part of the multidisciplinary management approach to IBD. In terms of primary therapy, polymeric and elemental enteral diets are an effective therapy for patients with acute Crohn's disease, offering an unrivaled safety profile and significant nutritional benefits. Enteral diets should be considered as primary therapy in children with Crohn's disease, especially in those with poor nutritional status or growth impairment, and in patients with severe drug-induced side effects. Total parenteral nutrition (TPN) does not have a primary therapeutic role in patients with IBD.