Lowered risk of nasopharyngeal carcinoma and intake of plant vitamin, fresh fish, green tea and coffee: a case-control study in Taiwan

A case-control study was conducted to evaluate the role of adult diet on nasopharyngeal carcinoma (NPC) in Taiwan. A total of 375 incident NPC cases and 327 controls matched to the cases on sex, age, and residence were recruited between July 1991 and December 1994. A structured questionnaire inquiring complete dietary history, socio-demographic characteristics, and other potential confounding factors was used in the personal interview. Unconditional logistic regression analysis was used to estimate multivariate-adjusted odds ratio (OR(adj)) with 95% confidence interval (CI) after accounting for known risk factors. Fresh fish (OR(adj), 0.56; 95% CI, 0.38-0.83 for the highest vs. lowest tertile of intake), green tea (OR(adj), 0.61; 95% CI, 0.40-0.91 for drinking ≥1 times/week vs. never) and coffee (OR(adj), 0.56; 95% CI, 0.37-0.85 for drinking ≥0.5 times/week vs. never) were inversely associated with the NPC risk. No association with NPC risk was observed for the intake of meats, salted fish, fresh vegetables, fruits and milk. Intake of vitamin A from plant sources was associated with a decreased NPC risk (OR(adj), 0.62; 95% CI, 0.41-0.94 for the highest vs. lowest tertile). The study findings suggest that certain adult dietary patterns might protect against the development of NPC.