Abstract: Objective To investigate the effects of vitamin D on serum iron (SI), ferritin(SF) and hepcidin (Hepc) in patients with nonalcoholic fatty liver disease (NAFLD). Methods There were 186 patients with NAFLD in this study. All these patients were divided into two groups according to the level of serum 25-hydroxyvitamin D3 [25(OH)D3)], deficient group (25(OH)D3≤20 μg/L, n=115) and non-deficient group (n=71). The age, gender, body mass index (BMI), blood pressure,serum lipids, alanine aminotransferase (ALT), aspartate aminotransferase (AST), gamma glutamyl transferase (GGT), fasting plasma glucose (FPG), fasting insulin (FINS), homeostasis model assessment for insulin resistance (HOMA-IR), SI, SF and Hepc were compared between the two groups. The correlations between 25(OH)D3 and serum markers of iron metabolism were analyzed. Results There was no significant difference in SI between the two groups (P＞0.05). The levels of BMI,FINS, SF, Hepc and HOMA-IR were significantly higher in deficient group than those of non-deficient group (P＜0.05). The pearson correlational analysis showed that 25(OH)D3 was negative related to SF (r=-0.328), Hepc (r=-0.314) and HOMA-IR (r=- 0.293, P＜0.05). Conclusion The deficiency of vitamin D causes iron overload in patients with NAFLD, and aggravates insulin resistance.

Key words: vitamin D, calcifediol, iron metabolism disorders, hepcidin, serum ferritin, nonalcoholic fatty liver disease, insulin resistance