Purpose: The purpose of the study was to evaluate the associations between the consumption of Zn, Cu, Fe, Na, K, Ca, and Mg and diabetic retinopathy (DR) in America through the National Health and Nutrition Examination Survey (NHANES) 2005–2008. Materials and Methods: The most representative 163 participants were 89 with DR and 74 without DR. Multivariate logistic regression was applied to estimate the correlation between the consumption of these metallic elements and the incidence of DR in 3 models. Weighted quantile sum (WQS) regression was used to compare the most obvious metals that influence DR risk. Finally, restricted cubic splines (RCSs) were used to investigate the potential nonlinear relationship between DR risk and zinc concentration. Results: Participants with DR had significantly greater zinc intake than did those without DR (DR: 13.66 ± 7.41, non-DR: 9.40 ± 5.61, P = 0.005). Logistic regression analysis revealed a marked positive linear relationship between zinc and the incidence of DR among the 7 metallic elements (odds ratio = 1.13, 95% confidence interval = 1.07–1.20, P < 0.001). The significant associations were consistent across the different adjustment models. However, there were no statistically significant associations between DR and the other 6 parameters. WQS regression revealed that zinc had the highest estimated weight (0.4236). The RCS revealed that there was no nonlinear relationship between zinc concentration and DR risk, with P = 0.609. Conclusion: According to the NHANES, participants with type 2 diabetes mellitus (T2DM) and a higher dietary zinc intake had a significantly increased risk of DR. Moreover, the relationship between zinc intake and DR was positive and linear.
Changli Liu (2026) studied this question.