Case-control study of diet and other risk factors for gastric cancer in Hawaii (United States).

Objective: To investigate the association of diet and other factors with gastric adenocarcinoma of the distal stomach.

Methods: Three hundred cases and 446 population-based controls were interviewed with a quantitative, food frequency questionnaire, which listed over 250 foods. The questionnaire also included information on smoking history, alcohol intake, education, medical history, medication use, and a family history of cancer.

Results: Cigarette smoking, family history of gastric cancer and personal history of gastric ulcer were positively associated with gastric cancer, while education and past use of non-steroidal anti-inflammatory drugs were inversely related to risk. The consumption of all vegetables, mainly dark green, light green, and yellow vegetables, reduced risk. Many of these vegetables contain beta-carotene, vitamin C, vitamin E or folate, which were also inversely related to gastric cancer risk. When these nutrients were analyzed simultaneously, the inverse association was mainly with beta-carotene. The intake of processed meats and bacon was positively associated with gastric cancer risk, but primarily in men. When we simultaneously adjusted these meats for the intake of the different vegetables, the association was no longer significant.

Conclusions: These findings provide additional support that the consumption of dark green and yellow vegetables are protective against adenocarcinoma of the distal stomach.