The study investigates potential causal relationships between dietary micronutrient intake and chronic kidney disease (CKD) development using Mendelian randomization (MR) in a Korean population. Data from over 5,000 adults without CKD at baseline were analyzed over a 12-year follow-up, focusing on genetically predicted intake levels of phosphorus, vitamin B2, vitamin B6, and vitamin C.
Results showed a significant negative association between genetically predicted vitamin B6 intake and CKD risk, suggesting a protective effect, and a possible positive association between vitamin C intake and CKD risk. No significant associations were found for phosphorus or vitamin B2. The findings suggest a potential role for vitamin B6 in kidney health and raise questions about high vitamin C intake. However, the authors caution that residual pleiotropy and weak instrument bias limit definitive conclusions.