Vitamin D and Vitamin D‐binding protein and risk of bladder cancer: A nested case‐control study in the Norwegian Janus Serum Bank Cohort

High circulating levels of vitamin D (25(OH)D) are suggested to reduce the risk of urinary bladder cancer (BC), but the evidence is weak, and several studies lack sufficient adjustment for potential confounders (e.g., smoking, body mass index (BMI), and physical activity). Moreover, few studies have investigated the role of vitamin D-binding protein (DBP) in this context. We conducted a matched nested case-control study including 378 cases and...