There have been few prospective studies relating diet to pancreatic cancer, with most having fewer than 100 cases and only one examining dietary nutrients. The authors prospectively examined dietary factors hypothesized to be associated with exocrine pancreatic cancer in the Alpha-Tocopherol, Beta-Carotene Cancer Prevention Study cohort in Finland. Of the 27,111 male smokers aged 50-69 years with complete dietary information, as ascertained from a self-administered dietary history questionnaire given at baseline (1985-1988), 163 developed pancreatic cancer from 1985 through November 1997. Cox proportional hazards models were used to estimate smoking- and age-adjusted hazard ratios and 95% confidence intervals. Energy-adjusted butter consumption and saturated fat intake were positively associated with pancreatic cancer (highest quintile vs. lowest: hazard ratio (HR) = 1.40, 95% confidence interval (CI): 0.87, 2.25 (p trend = 0.04), and HR = 1.60, 95% CI: 0.96, 2.64 (p trend = 0.02), respectively). Energy intake and energy-adjusted carbohydrate intake were inversely associated with the disease (highest quintile vs. lowest: HR = 0.62, 95% CI: 0.36, 1.07 (p trend = 0.05), and HR = 0.62, 95% CI: 0.37, 1.03 (p trend = 0.02), respectively). These results support the hypothesis that a high intake of saturated fat may increase the risk of pancreatic cancer in smokers, while greater intakes of energy and carbohydrate may reduce the risk.