VITAMIN D AND FATTY LIVER DISEASE: PATHOPHYSIOLOGICAL LINKS AND THERAPEUTIC POTENTIAL

Abstract

Fat accumulation within hepatocytes is a defining feature of Fatty Liver Disease (FLD), a condition that includes NonAlcoholic Fatty Liver Disease (NAFLD), its more severe form Non-Alcoholic Steatohepatitis (NASH), and Alcoholic Fatty Liver Disease (ALD). NAFLD, in particular, is closely linked to metabolic disturbances such as insulin resistance, chronic low-grade inflammation, and dyslipidemia. In recent years, growing attention has been directed toward vitamin D deficiency as a potential factor contributing to both the development and progression of this condition. Vitamin D, a fat-soluble secosteroid, is widely recognized for its role in calcium homeostasis, but it also plays important roles in immune function and metabolic regulation.This review brings together current evidence on vitamin D metabolism and explores its involvement in key processes relevant to NAFLD, including hepatic lipid handling, insulin sensitivity, inflammatory responses, and fibrotic changes. It also examines the mechanistic pathways through which vitamin D deficiency may influence disease progression. In addition, findings from epidemiological studies, interventional research, and clinical trials are evaluated to better understand the potential role of vitamin D supplementation in the management of NAFLD. By integrating these diverse lines of evidence, this review aims to provide a clear and evidence-based perspective for clinicians and researchers addressing NAFLD and its associated metabolic complications.