The high incidence of colon cancer in affluent societies has often been attributed to a high fat diet and, more in particular, the consumption of meat. The association of the consumption of meat and the intake of fat with risk of colon cancer was investigated in a prospective cohort study on diet and cancer, which is being conducted in the Netherlands since 1986 among 120,852 men and women, aged 55-69. The analysis was based on 215 incident cases of colon cancer (105 men and 110 women) accumulated in 3.3 years of follow-up, excluding cases diagnosed in the first year of follow-up. Dietary habits were assessed at baseline with a 150-item semiquantitative food frequency questionnaire. No trends in relative rates of colon cancer were detected for intake of energy or for the energy-adjusted intake of fats, protein, fat from meat, and protein from meat. Consumption of total fresh meat, beef, pork, minced meat, chicken, and fish was not associated with risk of colon cancer either. Processed meats, however, were associated with an increased risk in men and women (relative rate, 1.17 per increment of 15 g/day; 95% confidence interval, 1.03-1.33). The increased risk appeared to be attributable to one of the five questionnaire items on processed meat, which comprised mainly sausages. This study does not support a role of fresh meat and dietary fat in the etiology of colon cancer in this population. As an exception, some processed meats may increase the risk, but the mechanism is not yet clear.