Objectives: North-west Iran is a high-risk area for gastric cancer (GC). Dietary practices may increase risk of GC. For the first time, the diet-GC association in this area was assessed using a validated food frequency questionnaire.
Methods: Cases and controls were recruited in a population-based study. In addition to collecting dietary data using a food frequency questionnaire, Helicobacter pylori antibody level was measured. Multiple logistic regression models were used to estimate odds ratios for associations between dietary factors and GC among 286 cases and 304 controls.
Results: A positive association was estimated for total fat intake (OR = 1.33/20 g, 95% CI: 1.12-1.57) and risk of GC. Inverse associations were observed for vitamin C, iron, and zinc intake and risk of GC and its subgroups (cardia, non-cardia). Fruits and vegetables consumption and refrigerator use showed inverse associations (OR = 0.72/100 g, 95% CI: 0.65-0.80 and OR = 0.75/10 years, 95% CI: 0.60-0.95, respectively). Positive association was observed among those who preferred fried food (OR = 2.21, 95% CI: 1.45-3.37) or consumed highly salted/roasted seeds (OR = 1.97, 95% CI: 1.13-3.43).
Conclusion: GC in north-west Iran is associated with dietary practices: foods, nutrients and food preparation habits.