In summary, while there is mounting in vitro evidence that folate plays a significant role in both carcinogenesis and the growth of existing malignancies, it is not yet clear whether or not ingested folate plays a significant role in upper gastrointestinal cancers in humans. Our systematic review shows that dietary folate intake is associated with a decreased risk of esophageal and pancreatic cancer, but not for gastric cancer. However, the interpretation of these results is limited both by the low absolute number of studies, and by the high heterogeneity present in the majority of analyses. Future research should include prospective studies on folate and esophageal cancer, control for H. pylori in folate and gastric cancer studies, and include total folate intake measurements.
The authors have declared no conflicts of interest.
J Gastroenterol Hepatol. 2014;29(2):250-258. © 2014 Blackwell Publishing