Intake of specific carotenoids and flavonoids and the risk of gastric cancer in Spain

Objectives: To investigate the relationship between gastric cancer and the intake of specific carotenoids (alpha-carotene, beta-carotene, lutein, and lycopene) and flavonoids (quercetin, kaempferol, myricetin, and luteolin) u sing new data on their concentration in foods. Methods: Case-control study carried out in Spain that included 354 cases of gastric cancer and 354 controls, matched by age, gender, area of residence and hospital. Usual food intake was assessed using a dietary history quest ionnaire. Results: In a multivariate model adjusted for several dietary factors, no a ssociation was found between intake of any of the studied carotenoids and t he risk of gastric cancer. The adjusted OR of gastric cancer for the highes t quartile of total flavonoid intake versus the lowest quartile was 0.44 (9 5 percent confidence interval [CI] = 0.25-0.78; P for trend = 0.003). Kaemp ferol intake was found to be protective (OR = 0.48; CI = 0.26-0.88, P for t rend = 0.04) comparing the highest versus the lowest quartile of intake. A trend toward lower risk of stomach cancer with higher intake of quercetin w as also found. Concusions: The results of this study support the hypothesis that the well- established protective effect of fruit and vegetables against gastric cance r could, in part, be due to the presence of flavonoids.