Green Tea Consumption and Esophageal Cancer Risk: A Meta-analysis

Abstract

Background: The protective role of green tea against cancer is still unknown.

Objectives: To investigate the association between green tea consumption and esophageal cancer risk through meta-analysis.

Methods: We searched MEDLINE, EMBASE, Web of Science and Cochrane Library for studies on the relationship between green tea and esophageal cancer risk. We assessed heterogeneity (I²) and publication bias (Begg’s and Egger’s tests). Pooled relative risks (RRs) or odds ratios (ORs) with 95% confidence intervals (CIs) were calculated using random effects models.

Results: A total of 20 studies were included. The RRs for all studies was 0.65 (95% CI: 0.57–0.73), with I² = 75.3% and P = 0. In the subgroup analysis, the following variables showed marked heterogeneity: Asian (RR: 0.64; 95% CI: 0.56–0.73) and non-Asian countries (RR: 0.74; 95% CI: 0.45–1.03), female (RR: 0.55; 95% CI: 0.39–0.71) and male + female (RR: 0.64; 95% CI: 0.54–0.75), case–control study (RR: 0.62; 95% CI: 0.52–0.71), impact factor >3 (RR: 0.65; 95% CI: 0.56–0.75), impact factor <3 (RR: 0.64; 95% CI: 0.48–0.80), Newcastle–Ottawa Scale >7 (RR: 0.82; 95% CI: 0.66–0.97) and Newcastle–Ottawa Scale ≤7 (RR: 0.59; 95% CI: 0.49–0.68).

Conclusion: Green tea consumption could be a protective factor for esophageal cancer.

Acknowledgments

Yi Yu, Hai Long Liang and Jing Huang substantial contributions to conception and designed the data; Jian Zhang, Guang Yang, Jun Zhang and Hong Fa Zhu drafted the article critically for important intellectual content; and Jian Li final approval of the version to be published. We would like to thank the native English speaking scientists of Elixigen Company (Huntington Beach, California) for editing our manuscript.

Disclosure Statement

The authors report no conflicts of interests. We confirm that none of the authors are related to authors of studies included in the meta-analysis.