While systematic reviews predominantly find their foothold in clinical setting comparisons and evaluations of natural compound studies [25,26,27,28,29,30], our research undertook a meticulously orchestrated systematic review, aimed at penetrating the intricate realm of the association between the methylenetetrahydrofolate reductase rs1801133 polymorphism and the incidence of bladder cancer (BC). The gene discussed is MTHFR; the disease is urinary bladder cancer.