Effects of Vitamin and Antioxidant Supplements in Prevention of Bladder Cancer: a Meta-Analysis of Randomized Controlled Trials

J Korean Med Sci. 2017 Apr;32(4):628-635. doi: 10.3346/jkms.2017.32.4.628.


This study aimed to investigate the effects of vitamin and antioxidant supplements in the prevention of bladder cancer using a meta-analysis of randomized controlled trials (RCTs). Fourteen RCTs were included in the final analysis. In a fixed-effect meta-analysis, vitamin and antioxidant supplements showed no preventive effect for bladder cancer (relative risk [RR] = 1.04; 95% confidence interval [CI] 0.92-1.17; I² = 39.7%). Also, there was no preventive effect of these supplements in the subgroup meta-analyses by various factors such as type of supplements, type of cancer prevention, methodological quality, providers of supplements, type of control group, and number of participants. Among the subgroup analyses by type of supplements, beta-carotene supplementation alone marginally increased the risk of bladder cancer (RR = 1.44; 95% CI 1.00-2.09; I² = 0.0%; n = 3). The current meta-analysis found that vitamin and antioxidant supplements have no preventive effect against bladder cancer.

Keywords: Antioxidant; Bladder Cancer; Meta-Analysis; Randomized Controlled Trials; Vitamin.

Publication types

  • Meta-Analysis

MeSH terms

  • Antioxidants / therapeutic use*
  • Databases, Factual
  • Dietary Supplements
  • Humans
  • Randomized Controlled Trials as Topic
  • Risk
  • Urinary Bladder Neoplasms / pathology
  • Urinary Bladder Neoplasms / prevention & control*
  • Vitamins / therapeutic use*
  • beta Carotene / therapeutic use


  • Antioxidants
  • Vitamins
  • beta Carotene