Hemorrhoids are a frequently occurring disorder widely believed to be caused by chronic constipation. In the present study, the epidemiology of hemorrhoids was evaluated and compared with the epidemiology of constipation. The analysis was based on 4 data sources: from the United States, the National Health Interview Survey, the National Hospital Discharge Survey, and the National Disease and Therapeutic Index; from England and Wales, the Morbidity Statistics from General Practice. Results showed that 10 million people in the United States complained of hemorrhoids, corresponding to a prevalence rate of 4.4%. In both sexes, a peak in prevalence was noted from age 45-65 yr, with a subsequent decrease after age 65 yr. The development of hemorrhoids before age 20 yr was unusual. Whites were affected more frequently than blacks, and increased prevalence rates were associated with higher socioeconomic status. This was in contrast to the epidemiology of constipation, which demonstrated an exponential increase in prevalence after age 65 yr and was more common in blacks and in families with low incomes or low social status. The data presented illustrate differences in the epidemiologic behavior of hemorrhoids and constipation, calling the presumption of causality between constipation and hemorrhoids into question.