Association between tea intake and alcohol consumption and diabetes complications: A two sample Mendelian randomization study

Abstract

Abstract Background: Studies have indicated that there is a relationship between tea drinking, alcohol consumption, and a reduced risk of diabetes and its complications. However, there is currently no consensus on the potential relationships between tea drinking, alcohol consumption, and diabetes as well as its complications. In this study, we employed a two-sample Mendelian randomization (MR) analysis for the first time to systematically explore the causal relationships between tea intake, alcohol consumption, and diabetes as well as its complications. Methods: Genetic instruments for tea drinking were identified from a genome-wide association study (GWAS) involving 447,485 individuals. Genetic instruments for alcohol intake were identified from a GWAS involving 462,346 individuals. Summary data for diabetes and its complications were obtained from various GWAS meta-analyses. Causal effects between tea drinking, alcohol consumption, and diabetes as well as its complications were examined. Inverse variance-weighted Mendelian randomization (MR) analysis was conducted as the primary method for causal inference. Further sensitivity analyses were performed to ensure the robustness of the results. Results: The IVW assessment showed a causal relationship between alcohol intake and three diabetic complications. Type 2 diabetes with other specified/multiple/unspecified complications , Type 2 diabetes with ophthalmic complications and Type 2 diabetes with renal complications indicated an association with alcohol intake. However, there was horizontal pleiotropy in the study of alcohol intake and three diabetic complications, making the conclusions unreliable. The IVW assessment showed a causal relationship between tea intake and two diabetic complications. Type 1 diabetes with neurological complications, Type 1 diabetes with peripheral circulatory complications showed an association with tea intake. Conclusion: Our research shows that tea and alcohol consumption have a protective effect against diabetic complications.This research contributes to a deeper understanding of dietary influences on diabetes, offering potential directions for future research and public health advocacy.