Dietary fatty acid intake and the risk of pancreatic cancer: a dose-response meta-analysis of observational studies

Background: The impact of fatty acids on pancreatic cancer (PC) risk remains contentious, prompting evaluation through current observational evidence. This systematic review and dose-response meta-analysis of observational studies aim to examine the association between dietary polyunsaturated fatty acids (PUFAs), monounsaturated fatty acids (MUFAs), saturated fatty acids (SFAs), trans fatty acids (TFAs), and the risk of PC. Methods: We systematically searched PubMed, Scopus, Cochrane, and Web of Science until December 2024. We included cohort and case-control studies that reported risk ratios (RRs), odds ratios (ORs), or hazard ratios (HRs) with 95% confidence intervals (CIs). The Newcastle-Ottawa Scale (NOS) was used to evaluate the quality of the included studies. Results: Overall, 26 observational studies (15 case-control and 11 cohort) showed no significant associations between TFA, MUFA, PUFA, or SFA intake and PC risk. However, case-control studies indicated a significant positive association for SFA intake (OR: 1.43; 95% CI: 1.02-1.99) and an inverse association for PUFA intake (OR: 0.74; 95% CI: 0.59-0.94). No significant relationship was found for TFA or MUFA intake in case-control studies. Stratification by study design was conducted to address differences in bias, such as recall bias in case-control studies and longer follow-up periods in cohort studies. Conclusion: Our findings suggest that modifying dietary fatty acid intake may contribute to PC prevention. These results highlight the need for further research to confirm these associations, explore underlying mechanisms, and examine the impact of dietary patterns and fatty acid sources on PC risk.