Abstract & Overview
Type 2 diabetes mellitus (T2DM) and its microvascular complications are characterized by chronic inflammation, which arises as a consequence of persistent hyperglycemia and insulin resistance. In obese patients with T2DM, abdominal adiposity further contributes to metabolic imbalance and an increased inflammatory burden. During the inflammatory process in adipose tissue, proinflammatory cytokine levels rise, while anti-inflammatory cytokines decrease. Vitamin D has been increasingly recognized for its role in modulating inflammation, a key factor in the progression of T2DM and its associated complications. This review examines the relationship between vitamin D status and inflammatory markers in individuals with T2DM, highlighting the potential mechanisms through which vitamin D influences immune responses and metabolic pathways. Recent clinical and experimental studies investigating the impact of vitamin D deficiency on chronic inflammation (such as via tumor necrosis factor alpha, interleukins, and C-reactive protein), insulin resistance, and the development of diabetic complications including cardiovascular disease, nephropathy, and neuropathy are discussed. Furthermore, the review elaborates on the potential benefits of vitamin D supplementation in managing inflammation and mitigating disease progression. Although existing evidence suggests a strong link between vitamin D and inflammatory processes in T2DM, further well-designed clinical trials are needed to establish causality and determine optimal supplementation strategies.