Intakes of folate, methionine, vitamin B6, and vitamin B12 with risk of esophageal and gastric cancer in a large cohort study

BACKGROUND: Nutrients in the one-carbon metabolism pathway may be involved in carcinogenesis. Few cohort studies have investigated the intakes of folate and related nutrients in relation to gastric and esophageal cancer. METHODS: We prospectively examined the association between self-reported intakes of folate, methionine, vitamin B6, and vitamin B12 and gastric and esophageal cancer in 492 293 men and women. RESULTS: We observed an elevated risk of esophageal squamous cell carcinoma with low intake of folate (relative risk (95% confidence interval): Q1 vs Q3, 1.91 (1.17, 3.10)), but no association with high intake. Folate intake was not associated with esophageal adenocarcinoma, gastric cardia adenocarcinoma, or non-cardia gastric adenocarcinoma. The intakes of methionine, vitamin B6, and vitamin B12 were not associated with esophageal and gastric cancer. CONCLUSION: Low intake of folate was associated with increased risk of esophageal squamous cell carcinoma.