Dietary carotenoids and vitamin A are associated with lower gastric cancer risk and favorable inflammatory and oxidative stress biomarkers: an incident case– control study

Background Dietary carotenoids and vitamin A may contribute to gastric cancer (GC) prevention through anti-inflammatory and antioxidant mechanisms; however, epidemiological evidence remains limited. We investigated the associations of total and individual carotenoid and vitamin A intakes with GC and their relationships with inflammatory/oxidative stress biomarkers. Methods The case–control study included 177 adults (82 GC incidence cases/95 controls). A validated 168-item food frequency questionnaire assessed dietary intakes of individual carotenoids and preformed vitamin A. Metabolic biomarkers, lipid profile, inflammatory/oxidative stress markers [e.g., high-sensitivity C-reactive protein (hs-CRP), tumor necrosis factor-alpha (TNF- α ), interleukins (6/1 β /10/4), total antioxidant capacity (TAC), and malondialdehyde (MDA)] were measured. Multivariable logistic regression models estimated odds ratios (ORs) for GC risk; linear regression models examined associations between carotenoid intakes and biomarkers. Results Total carotenoid (mg/d; OR: 0.86, 95%CI: 0.81–0.98), β -carotene (mg/d; OR: 0.77, 95%CI: 0.65–0.90) and vitamin A (mg RAE/d; OR: 0.29, 95%CI: 0.09–0.95) intakes, as continuous variables, and also as binary variables (based on the median cut-offs), in all models (also adjusted for age, sex, smoking, education, marital status, physical activity, cancer history, H. pylori , NSAIDs intake, body mass index, total energy intake), were inversely associated with GC odds. In fully adjusted models, higher total carotenoid intake (mg/d) was associated with lower LDL-c ( β : −1.60, 95%CI: −2.91, −0.25) and IL-6 ( β : −7.92, 95%CI: −14.00, −2.00); lycopene (mg/d) with higher LDL-c ( β : 2.030, 95%CI: 0.27, 4.31) and vitamin A intake (mg RAE/d) with lower TNF- α ( β : −12.12, 95%CI: −24.71, −0.47) and higher TAC ( β : 0.64, 95%CI: 0.001, 1.27). Conclusion Higher intakes of total carotenoids and vitamin A were associated with lower odds of GC and more favorable profiles of inflammatory/oxidative stress biomarkers. These findings support an inverse association between carotenoid-rich dietary patterns and gastric carcinogenesis.