Total, unprocessed, and processed red meat intake in relation to the risk of pancreatic cancer: A systematic review and dose-response meta-analysis of prospective cohort studies

Data on the association between red meat from both processed and unprocessed sources and risk of pancreatic cancer is controversial. Therefore, this study summarized current evidence on the relationship between red and processed red meat intake and pancreatic cancer risk through a meta-analysis. A systematic search was conducted on PubMed, ISI Web of Science and Scopus for prospective cohorts up to October 2024. Hazard ratio (HR) and 95 % confidence intervals (CIs) for the highest vs. the lowest category of the exposures were combined using random-effects models. Dose-response relations were explored by one-stage weighted mixed effects meta-analysis. 19 studies involving 4,291,065 participants with 13,820 pancreatic cancer cases were included. The highest intake of total red meat was positively related to risk of pancreatic cancer (Pooled HR: 1.12, 95%CIs: 1.01, 1.24; I2: 36.5 %, PQ-test: 0.10). Such association was not significant for unprocessed (Pooled HR: 1.05, 95%CIs: 0.88, 1.24; I2: 66.6 %, PQ-test: 0.002) and processed (Pooled HR: 1.02, 95%CIs: 0.86, 1.21; I2: 66.0 %, PQ-test: 0.001) red meat intake. No significant association was observed between each 3 serving/wk of total, unprocessed, and processed red meat and risk of pancreatic cancer. Also, no evidence for a nonlinear association was found for all associations. This meta-analysis suggests a positive relation between the highest consumption of total red meat and pancreatic cancer. However, this relation was not substantial in terms of unprocessed and processed red meat.