Standard tea intake is causally associated with a reduced risk of wet age-related macular degeneration: a Mendelian...

Researchers have posited that increased consumption of tea and coffee may be associated with more favorable treatment outcomes in patients with age-related macular degeneration (AMD). However, there is no clear evidence regarding the causal associations. To delve deeper into this potential connection, scientists used a rigorous method known as Mendelian randomization (MR). This technique was used to explore the causal impact of tea and coffee consumption on the development or progression of AMD. With the aim of investigating the cause-and-effect relationship between 16 tea- and coffee-consuming subtypes and 3 AMD, we designed a two-sample MR study using comprehensive data from genome-wide association studies (GWAS). The major approach adopted was inverse variance weighting (IVW). Furthermore, we implemented complementary methods like the weighted median (WM), weighted mode, and MR-Egger to strengthen our findings. Sensitivity analyses, including MR-Egger, MR-PRESSO, leave-one-out, and Cochran's Q tests, were used to validate results, explore heterogeneity and pleiotropy, and pinpoint potential biases. Two hundred and sixty-eight instrumental variables were selected for MR analysis. The results showed that standard tea intake may be a protective factor for wet AMD [odds ratio (OR) = 0.7076, 95% confidence interval (CI) = 0.5776-0.8668, P = 8 × 10^-4, P_FDR = 0.0402]. Sensitivity analysis suggests that the results are robust. Our findings provide genetic evidence that standard tea intake is a protective factor against wet AMD, providing new insights into early risk stratification and prevention strategies for the disease.NEW & NOTEWORTHY This study investigates the potential causal relationship between tea and coffee consumption and age-related macular degeneration (AMD) using Mendelian randomization. Analyzing data from genome-wide association studies, we focused on 16 beverage subtypes and 3 AMD conditions. Our findings suggest that standard tea consumption may protect against wet AMD, with robust evidence supporting this link. The results offer new insights into risk stratification and prevention strategies for AMD, highlighting the importance of dietary factors in eye health.