Associations between dietary folate intake and risks of esophageal, gastric and pancreatic cancers: an overall and dose-response meta-analysis

// Wen Liu 1, * , Heng Zhou 1, * , Yaoqi Zhu 2, 3 and Chaorong Tie 3 1 Department of Pathology, Renmin Hospital of Wuhan University, Wuhan, 430060, Hubei Province, P. R. China 2 Department of Stomatology, Zhongnan Hospital of Wuhan University, Wuhan, 430071, Hubei Province, P. R. China 3 Department of Stomatology, Taikang Tongji Hospital, Wuhan, 430000, Hubei Province, P. R. China * These authors have contributed equally to this work Correspondence to: Chaorong Tie, email: 414825917@qq.com Heng Zhou, email: hengzhou117@163.com Keywords: esophageal cancer, gastric cancer, pancreatic cancer, dose-response analysis, meta-analysis Received: February 20, 2017 Accepted: May 22, 2017 Published: June 28, 2017 ABSTRACT There are still some controversies on the association between dietary folate intake and the risk of upper gastrointestinal cancers including esophageal, gastric and pancreatic cancers. Hence, a comprehensive meta-analysis on all available literatures was performed to clarify the relationship between dietary folate intake and risks of upper gastrointestinal cancers. An electric search was performed up to December 12 th , 2016 within the PubMed, MEDLINE AND EMBASE databases. Ultimately, a total of 46 studies which evaluated the association between folate intake and risks of upper gastrointestinal cancers were included. According to the data from included studies, the pooled results showed significant association between folate intake and esophageal (OR = 0.545, 95%CI = 0.432-0.658), gastric (OR=0.762, 95%CI=0.648-0.876) and pancreatic (OR=0.731, 95%CI=0.555-0.907) cancers. Linearity dose-response analysis indicated that with 100μg/day increment in dietary folate intake, the risk of esophageal, gastric and pancreatic cancers would decrease by 9%, 1.5% and 6%, respectively. These findings indicated that higher level of dietary folate intake could help for preventing upper gastrointestinal cancers including esophageal, gastric and pancreatic cancers.