Recent theories have postulated that low fiber diets are related to colon cancer and diverticulosis, and to atherosclerosis. These theories are based on British and African diet history information. There has been no recent assessment of fiber intake in an area of high incidence of colonic disease in the United States. Using recall diet histories in subjects with no disease and with colon disease, and correcting our data to account for any loss in recall history, we find a low daily fiber intake in all 21 subjects evaluated, mean 3.5 g, range 1.6 to 11 g. There was no statistical difference in intake among patients with or without colon disease. The data agree with the British findings. Since the incidence of the diseases in question is not uniform in the United States it is suggested that diet surveys are needed in areas where colon carcinoma is of low incidence.