The prevalence of adenomatous and hyperplastic polyps of the colon and the degree of involvement of the aorta by atherosclerotic lesions were evaluated in 842 autopsies from New Orleans. A positive statistical association between the two variables was found in white males under 75 years of age. In black males a positive correlation between atherosclerotic lesions and adenomatous (but not hyperplastic) polyps was found. The most extensive involvement of the aorta by atherosclerosis was found in patients in whom adenomatous and hyperplastic polyps coincided. The possibilities that dietary factors may account for these findings and its relevance in relation to colon cancer and coronary heart disease are discussed.