Dietary habit and risk of rheumatoid arthritis: a mendelian randomization study identifying protective and risk factors.

Purpose: Dietary habit significantly contributes to the initiation and progression of rheumatoid arthritis (RA). Dietary choices intersect with a range of clinical and societal factors. The utilization of cross-sectional methodologies in numerous studies poses a challenge in establishing definitive causality for the noted associations. Moreover, within identical food categories, specific items may elicit diverse effects on the pathogenesis of RA, and the correlation between several prevalent food items or beverages and RA remains inadequately explored.

Methods: We performed a two-sample Mendelian Randomization (MR) study to evaluate the causal impact of 27 distinct dietary habits and RA susceptibility. These dietary-related phenotypes encompass both the relative intake of the four macronutrients (fat, protein, carbohydrates, and sugar) and 23 specific single food intake. Several filtering steps were employed to select eligible genetic instruments strongly associated with each of the traits. The random-effects inverse-variance weighted, weighted median, and MR-Egger methods were employed for MR estimations. Sensitivity analyses and power calculations were executed to ensure the robustness of our study.

Results: After rigorous single-nucleotide polymorphism (SNP) filtering procedures, 611 SNPs were included in our ongoing investigations. The consumption of dried fruit, bread, and alcohol emerged as protective factors, while beef, processed meat, and coffee intake were identified as risk factors. The robustness of our study was confirmed through the outcomes of sensitivity analysis and power calculation.

Conclusion: The ongoing investigations furnish evidence that accentuates the influence of diet on RA disease activity, underscoring the importance of delineating the optimal nutritional lifestyle for RA patients.