Wine consumption and colorectal cancer risk: a meta-analysis of observational studies

There were inconsistent results with respect to the correlation between consumption of wine and the development of colorectal cancer (CRC). We carried out a meta-analysis to investigate this issue. We included observational studies on the aforementioned relationship according to a literature search of Embase and Pubmed from inception till 28 February 2017. The summary relative risk (SRR) and 95% confidence intervals (CI) were calculated using a random-effects model. A total of eight case-control and nine cohort studies were identified, involving 12 110 CRC cases. The study showed that wine drinking was not associated with any greater risk for CRC (SRR=0.99, 95% CI: 0.89-1.10; Pheterogeneity<0.001) compared with nondrinkers. The subgroup analyses indicated that null associations were observed in men and women for colon and rectal cancer. Neither light to moderate (<2 drinks/day; SRR=0.93, 95% CI: 0.80-1.08, I= 69.2%) nor heavy (≥2 drinks/day; SRR=1.00, 95% CI: 0.86-1.16, I= 39.9%) consumption of wine was associated statistically with CRC risk. This meta-analysis suggests that any wine consumption was not associated with the risk of CRC. Null associations were shown in men and women for colon and rectal cancer.