Constipation in institutionalized elderly is a common and difficult problem. Thirty-three institutionalized demented patients with severe constipation were given a high-bran bread instead of their accustomed laxatives. Changes in defecation habits, food and liquid intake, and metabolic status were registered. During the high-bran bread treatment period, the number of bowel evacuations and the estimated volume of feces increased. The total laxative consumption (doses given per day) decreased by 93 per cent. Nutritional data and metabolic status were unchanged during the high-bran bread period except for a reduction of the postprandial blood glucose response after the glucose tolerance test.