Nutrition is well-recognized as a necessary component of educational programs for physicians. This is to be valued in that of all factors affecting health in the United States, none is more important than nutrition. This can be argued from various perspectives, including health promotion, disease prevention, and therapeutic management. In all cases, serious consideration of nutrition related issues in the practice is seen to be one means to achieve cost-effective medical care. These modules were developed to provide more practical knowledge to health care providers, and in particular primary care physicians. This module is designed to familiarize physicians with the current modes of diet therapy in the treatment of gastrointestinal diseases most commonly encountered by primary care physicians. The diseases discussed include peptic ulcer disease, reflux esophagitis, gallbladder disease, lactose intolerance, diverticulosis, Crohn's disease, ulcerative colitis, and irritable bowel syndrome. Included are learning goals and objectives, self-checks of achievement with regard to goals, and references for the physician and for the physician to give to the patient. The appendices include a list of caffeine and theobromine content in selected foods, and a list of the fiber content of selected foods. (CW)