Nutritional therapy in Crohn's disease.

The value of nutritional support in the prevention and treatment of malnutrition in Crohn's disease is undisputed but its role in primary therapy continues to be debated. Controlled trials have demonstrated that enteral nutrition induces remission rates comparable to that of corticosteroid therapy in Crohn's disease and remains the treatment of choice for specific subgroups such as children with signs of growth impairment and patients with intolerable steroid-induced side effects. The mechanism by which an enteral diet induces remission in Crohn's disease is unclear. Bowel rest, reduced antigenic load, nutritional effects, the provision of trophic amino acids, modification of gut flora, intestinal permeability, or fecal pH have been proposed. Equally, the fat profile of the feed may reduce pro-inflammatory ecosanoid synthesis and thus modify disease activity. Maintaining long-term remission remains a challenge in the management of this disease. Cyclic administration of enteral diets, maintenance drug therapy, fat manipulated formulas, or fish oil therapy may be strategies to prolong diet-induced remission. In the future, nutrient derivatives that play a role in the protective processes of the intestinal mucosa may have application in nutritional therapy in Crohn's disease.