Dietary Lycopene Intake and Gastric Cancer Risk: Findings from a Case-Control Study

Background/Objectives: Lycopene, a red lipophilic carotenoid hydrocarbon pigment found primarily in tomatoes and other red/pink fruits and vegetables, has anti-inflammatory, anticarcinogenic and cardioprotective properties. There is a lack of evidence regarding the effect of lycopene intake on gastric cancer risk in the Asian population. We, thus, evaluate the association between lycopene intake and gastric cancer risk in a hospital-based case-control study, including 1182 incident cases of gastric cancer and 2995 controls in Vietnam. Methods: Lycopene intake was derived from a semi-quantitative, validated food frequency questionnaire. An unconditional logistic regression model was performed to estimate the odds ratios (ORs) and 95% confidence intervals (CIs) for gastric cancer risk in relation to lycopene intake, adjusted for potential confounding factors. Results: Overall, there was a dose-response inverse association between lycopene intake and gastric cancer risk (OR_{per-SD increment} = 0.88, 95% CI: 0.81-0.95; P_trend = 0.002). Compared with quintile 1 (the lowest quintile), the ORs and 95% CIs of gastric cancer for quintiles 2, 3, 4 and 5 of the lycopene intakes were 0.63 (0.51-0.79), 0.64 (0.51-0.80), 0.65 (0.52-0.81) and 0.62 (0.50-0.78), respectively. A similar pattern of inverse association between lycopene intake and gastric cancer risk was seen only in females, ever alcohol drinkers, and individuals with H. pylori negative status, without type 2 diabetes and with blood group B (all P_{heterogeneity} > 0.05). Conclusions: We observed a reduced risk of gastric cancer in individuals with higher lycopene intake in the Vietnamese population, regardless of BMI or smoking status. Our results have great implications for a healthy dietary pattern (i.e., lycopene with major sources from fruits and vegetables) for strategies in the prevention and control programs of gastric cancer in low-and middle-income countries.