NUTRITION AND GASTROINTESTINAL-DISEASE

Nutrition and intestinal function are intimately interrelated. The chi ef purpose of the gut is to digest and absorb nutrients in order to ma intain life. Consequently, chronic gastrointestinal (CI) disease commo nly results in malnutrition and increased morbidity and mortality. For example, studies have shown that 50-70% of adult patients with Crohn' s disease were weight-depleted and 75% of adolescents growth-retarded. On the other hand, chronic malnutrition impairs digestive and absorpt ive function because food and nutrients are not only the major trophic factors to the gut but also provide the building blocks for digestive enzymes and absorptive cells. For example, recent studies of ours hav e shown that a weight loss of greater than 30% accompanying a variety of diseases was associated with a reduction in pancreatic enzyme secre tion of over 80%, villus atrophy and impaired carbohydrate and fat abs orption. Finally, specific nutrients can induce disease, for example, gluten-sensitive enteropathy, whilst dietary factors such as fibre, re sistant starch, short-chain fatty acids, glutamine and fish oils may p revent gastrointestinal diseases such as diverticulitis, diversion col itis, ulcerative colitis, colonic adenomatosis and colonic carcinoma. The role of dietary antigens in the aetiology of Crohn's disease is co ntroversial, but controlled studies have suggested that elemental diet s may be as effective as corticosteroids in inducing a remission in pa tients with acute Crohn's disease. In conclusion, nutrition has both a supportive and therapeutic role in the management of chronic gastroin testinal diseases. With the development of modern techniques of nutrit ional support, the morbidity and mortality associated with chronic GI disease can be reduced. On the other hand, dietary manipulation may be used to treat or prevent specific GI disorders such as coeliac diseas e, functional bowel disease, Crohn's disease and colonic neoplasia. Th e future development of nutria-pharmaceuticals is particularly attract ive in view of their low cost and wide safety margins.