Review of meat and caffeine and the risk of bladder cancer

Bladder cancer (BCa) is a main health issue in both developed and developing countries, especially for men with an incidence that is three to five times greater than that of women. The majority of bladder cancer occurs in males and there is a 14-fold variation in the incidence internationally. About 1,596,670 new cancer cases were diagnosed in 2011. This estimate did not include carcinoma in situ (noninvasive cancer) of any site except urinary bladder. It is commonly known that nutrition has a role in preventing cancer in general. Additionally, new dispute has risen over the effect of dietary factors such as meat and coffee in bladder cancer, which has yielded contradicting results. The review relied on previous researches and studies related to our assumption that meat and caffeine intake is not proved to be directly related to BCa. The study showed that there is no credible evidence stating that BCa is the result of meat and caffeine intake. This was due to the contradiction found in the studies referred to or consulted in the study. The lack of statistical association of meat types, the different methods of cooking, samples under study, and lifestyle enrollment are all considered important variables that were neglected in previous researches. These limitations supported the lack of credibility of such studies that correlated BCa to meat and caffeine intake.