The Relationship between Food Intake and Bladder Cancer: A Case Control Study

Background & aim: Bladder cancer is the second most common cancer of the urinary tract worldwide and the third most common cancer among Iranian males. Despite the relative high incidence of bladder cancer in Iran, no study has examined the relationship between dietary factors and bladder cancer. The aim of the present study was to investigate this relationship. Methods: The present case-control study was carried out on fifty-five patients with bladder cancer and including 110 cancer-free patients as controls. Dietary intake was evaluated using a food frequency questionnaire. To investigate the relationship between food items and bladder cancer, the subjects were classified according to the tertile of food items. The odds ratio was calculated for each tertile and the first tertile was considered as the reference group. Results: Our findings revealed that among food groups, animal fat (OR=19.76), fat (OR=12.92), junk foods (OR=8.1), organ meat (OR=5.47), processed meat (OR=5.34) and sweets (OR=3.62) were involved in the development of bladder cancer. In bladder carcinogenesis, an inverse association was recorded between consumption of low fat dairy products (OR=0.31), yoghurt (OR =0.14), fish (OR = 0.13), specific fruits (OR=0.13) and the development of bladder cancer. Conclusion: Animal products and sources of saturated fat are associated with an increased in risk of bladder cancer. The protective effect of olive oil, specific fruits, vegetables, low-fat dairy fermented was observed to reduce the risk of bladder cancer