Epidemiology of gastrointestinal disorders.

Irritable bowel syndrome occurs most frequently in young adults in response to emotional and other factors. The 20th century western epidemic of diverticular disease may be linked to low dietary fiber intake. Peptic ulceration is determined by genetic and environmental factors including tobacco and coffee. Aspirin specifically predisposes to gastric ulcer. The incidence of peptic ulcer is declining. Crohn's disease is increasing in frequency although the incidence of ulcerative colitis is fairly steady. Gastrointestinal cancer is closely related to dietary factors including ingested procarcinogens, excessive carbohydrate, fat and animal protein. There is potential for control of some intestinal cancers.