Efficacy of Vitamin C Supplements in Prevention of Cancer: A Meta-Analysis of Randomized Controlled Trials.
10.4082/kjfm.2015.36.6.278
- Author:
Bobae LEE
1
;
Seung Won OH
;
Seung Kwon MYUNG
Author Information
1. Huntington University, Huntington, USA.
- Publication Type:Meta-Analysis ; Original Article
- Keywords:
Vitamin C;
Ascorbic Acid;
Cancer;
Randomized Controlled Trials;
Meta-Analysis
- MeSH:
Ascorbic Acid*;
Follow-Up Studies;
Mortality;
Smoke;
Smoking;
Vitamins*
- From:Korean Journal of Family Medicine
2015;36(6):278-285
- CountryRepublic of Korea
- Language:English
-
Abstract:
BACKGROUND: Previous randomized controlled trials (RCTs) have reported inconsistent findings regarding the association between vitamin C supplementation and the risk of cancer. METHODS: We performed a meta-analysis of RCTs to investigate the efficacy of vitamin C supplements for prevention of cancer. We searched the PubMed, EMBASE, and Cochrane Library databases in November 2014 using common keywords related to vitamin C supplements and cancer. RESULTS: Among 785 articles, a total of seven trials were identified, which included 62,619 participants; 31,326 and 31,293 were randomized to vitamin C supplementation and control or placebo groups, respectively, which were included in the final analysis. A fixed-effects meta-analysis of all seven RCTs revealed no significant association between vitamin C supplementation and cancer (relative risk, 1.00; 95% confidence intervals, 0.95-1.05). Similarly, subgroup meta-analysis by dose of vitamin C administered singly or in combination with other supplements, follow-up period, methodological quality, cancer mortality, gender, smoking status, country, and type of cancer also showed no efficacy of vitamin C supplementation for cancer prevention. CONCLUSION: This meta-analysis shows that there is no evidence to support the use of vitamin C supplements for prevention of cancer.
