Fruit and vegetable consumption and risk of bladder cancer: a prospective cohort study

Fruit and vegetable consumption has been inconsistently associated with risk of bladder cancer. We used data from a prospective population-based cohort study of 82,002 Swedish women and men to examine the association between fruit and vegetable consumption and bladder cancer incidence. Diet was assessed with a validated food frequency questionnaire. During a mean follow-up of 9.4 years, 485 incident cases of bladder cancer were identified in the Swedish cancer registries. We found no statistically significant association between intakes of total fruits and vegetables, total fruits, or total vegetables and bladder cancer risk after adjustment for age, sex, education, and cigarette smoking. The multivariate rate ratios (95% confidence intervals) comparing the highest with the lowest quartile of intake were 0.80 (0.60-1.05) for total fruits and vegetables, 0.93 (0.69-1.25) for fruits, and 0.89 (0.67-1.19) for vegetables. Likewise, no associations were observed for citrus fruits, cruciferous vegetables, or green leafy vegetables. The associations did not differ by sex or smoking status. In conclusion, findings from this prospective study suggest that fruit and vegetable intakes are not likely to be appreciably associated with the risk of bladder cancer.