Dietary Patterns and Risk of Lung Cancer: A Systematic Review and Meta-Analyses of Observational Studies.

PubMed, Embase, and Web of Science were systematically searched from inception to February 2023. Random-effects models were used to pool relative risks (RR) on associations with at least two studies. Twelve studies reported on data-driven dietary patterns, and 17 studies reported on a priori dietary patterns. A prudent dietary pattern (high in vegetables, fruit, fish, and white meat) tended to be associated with a lower risk of lung cancer (RR = 0.81, 95% confidence interval [CI] = 0.66-1.01, n = 5). In contrast, Western dietary patterns, characterized by higher intakes of refined grains and red and processed meat, were significantly positively associated with lung cancer (RR = 1.32, 95% CI = 1.08-1.60, n = 6). Healthy dietary scores were consistently associated with a lower risk of lung cancer (Healthy Eating Index [HEI]: RR = 0.87, 95% CI = 0.80-0.95, n = 4; Alternate HEI: RR = 0.88, 95% CI = 0.81-0.95, n = 4; Dietary Approaches to Stop Hypertension: RR = 0.87, 95% CI = 0.77-0.98, n = 4; Mediterranean diet: RR = 0.87, 95% CI = 0.81-0.93, n = 10) while the dietary inflammatory index was associated with a higher risk of lung cancer (RR = 1.14, 95% CI = 1.07-1.22, n = 6). Our systematic review indicates dietary patterns characterized by a higher intake of vegetables and fruits, a lower intake of animal products, and anti-inflammation may be associated with a reduced risk of lung cancer.