Although many foods have been suggested to play a role in the cause of IBD, there are not yet definitive data to support diet as a cause of either CD or UC. Malnutrition is a common occurrence in IBD, and this must be considered in the treatment of these diseases. Nutritional support in IBD has limited use as primary therapy (Table 2). Even though parenteral and enteral nutrition have been associated with remission, relapse frequently occurs when normal food intake is resumed. Likewise, fistulae may resolve with aggressive, nutritional therapy, but they frequently recur with reinstitution of food. In short bowel syndrome caused by extensive intestinal resection performed in CD, parenteral nutrition provides an important mode of therapy. In addition, perioperative use of nutritional support may decrease the incidence of postoperative complications in patients who are malnourished. Nutritional support in pediatric patients with CD who have growth failure has been effective in stimulating growth.