Increased B vitamin, methionine intake of no benefit for gastric cancer risk

Dietary intakes of folate, vitamin B6, vitamin B12, and methionine offer no protection against the risk of developing gastric cancer, a study has found.

The analysis used data from the Japan Public Health Center–based Prospective Study and included 86,820 Japanese individuals who completed a validated food frequency questionnaire with 138 food items.

Researchers performed Cox proportional hazards regression to examine the associations between dietary intakes of B vitamins and methionine and the risk of gastric cancer, according to sodium intake. Estimates were adjusted for factors such as Helicobacter pylori and atrophic gastritis.

A total of 2,269 incident gastric cancer cases were documented over a median follow-up of 15.4 years. The risk of gastric cancer showed no association with any of the dietary intakes of folate, vitamin B6, vitamin B12, or methionine.

In the stratified analysis by sodium intake, folate intake was positively associated with the risk of gastric cancer among participants with a high sodium intake (≥4.5 g/day; hazard ratio [HR], 1.28, 95 percent confidence interval [CI], 1.06–1.56; p_trend=0.001, p_interaction=0.02). On the other hand, this association was not observed among participants with low sodium intake (<4.5 g/day; HR, 0.94, 95 percent CI, 0.73–1.21; p_trend=0.49).

The findings suggest that the increased intake of B vitamins and methionine plays no role in gastric cancer risk in populations with adequate dietary intake of the said nutrients.