Recent studies are indicative of substantial progress in understanding the dose-response relation between the incidence of total and lung cancer and environmental cadmium exposure. We conducted a meta-analysis of population studies that examined the risk of cancer in relation to lifetime exposure to cadmium. We searched MEDLINE, Web of Science, and relevant reviews until August 2014 for studies on the association between cancer risk and cadmium exposure. Eligible studies had to include an estimate of lifetime exposure to cadmium as reflected by the urinary cadmium concentration and adjustment of the cancer risk at least for age and smoking. We pooled relative risk across the studies estimates for cancer and lung cancer using variance-weighted random-effect models and expressed association sizes for a twofold increase in urinary cadmium, thereby respecting the continuous nature of the association. The meta-analysis included 20,459 participants from three prospective population studies. The average urinary cadmium concentration across populations ranged from 0.25 to 0.93 A mu g/g creatinine. The relative risk of total cancer, associated with a doubling of the urinary cadmium concentration, ranged across the different studies from 1.18 to 1.31, and the pooled relative risk was 1.22 (95 % CI 1.13-1.31; p