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.

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.

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.

Low intake of folate was associated with increased risk of esophageal squamous cell carcinoma.