Consumption of Foods and Micronutrients and the Risk of Cancer of the Biliary Tract

Background. Gallstones and obesity have been suggested as risk factors for cancer of the biliary tract. Since both factors are related to diet, we studied the relationship between dietary intake and the cancer of interest in a population-based case-control study. Methods. The study population comprised 111 patients and 480 controls. Food intake was assessed by means of a semiquantitative food frequency questionnaire. Estimates of the intake of foods and micronutrients were obtained from cases and controls themselves (direct respondents) or from relatives (indirect respondents). Participants were categorized into tertiles of intake. Risk ratios were estimated by logistic regression analysis. Results. The major findings are a monotonic decrease in risk associated with the consumption of vegetables (ORs 1.0, 0.7, 0.4; P value trend