Gülten TARHAN, Ali Uğur USLU
Journal of Basic and Clinical Health Sciences - 2026;10(1):13-20
Purpose: Low levels of vitamin D (25-[OH]D) represent a common health problem, recently linked to chronic conditions such as metabolic syndrome (MetS), cardiovascular diseases, and type 2 diabetes mellitus. This study aimed to investigate the relationship between vitamin D levels, insulin resistance (IR), and MetS. Material and Methods: This retrospective study included 52 MetS patients diagnosed per the National Cholesterol Education Program Adult Treatment Panel III criteria and 74 age- and sex-matched healthy controls. IR was defined using a HOMA-IR threshold of >=2.5. Participants were divided into four groups: group 1 (MetS IR+, n=31), group 2 (MetS IR-, n=21), group 3 (healthy IR+, n=22), and group 4 (healthy IR-, n=52). Results: Mean 25-(OH)D levels were significantly lower in MetS patients (17.3+/-9.1 ng/mL) compared to controls (25.5+/-11.9 ng/mL, P<0.0001). Among the groups, 25-(OH)D levels differed significantly (16.9+/-9.4, 18.6+/-8.5, 25.8+/-15.2, and 25.3+/-9.3 ng/mL; P=0.001). Logistic regression analysis identified 25-(OH)D as an independent predictor of MetS IR+ (P=0.004). Conclusion: Vitamin D deficiency appears to play a role in the pathogenesis of MetS and IR. Furthermore, it may serve as a predictor of insulin resistance in MetS patients.
