Lifestyle factors and the course of diverticular disease.

The dramatic increase in the prevalence of diverticular disease after industrialization has led to the belief that diet and lifestyle factors play a significant role in its pathogenesis. Dietary fiber deficiency has received the most attention, although data are limited and conflicting. Two recent cross-sectional studies found no association between fiber intake and diverticulosis, and one found a positive association. However, fiber may improve symptoms associated with uncomplicated diverticulosis and decrease the risk of diverticulitis. Red meat intake may also increase the risk of diverticular symptoms and complications. Contrary to a long-standing belief, a large prospective study found that nuts and corn did not increase the risk of diverticulitis or diverticular bleeding. A number of case-control and prospective studies have found positive associations between obesity and diverticular complications. Central obesity may be particularly important. Vigorous physical activity appears to reduce the risk of diverticulitis and diverticular bleeding. Findings regarding smoking and diverticular complications have been inconsistent, but suggest that smokers are at increased risk for complications, particularly perforation. Alcohol may increase the risk of asymptomatic diverticulosis and diverticulitis. Research is needed to define the role of lifestyle modification in the primary and secondary prevention of diverticulosis and its complications.