VDR and vitamin D deficiency: Vitamin D deficiency may result in IR, which could affect lipoprotein metabolism resulting in increased TG and reduced HDL levels.[36] In contrast, studies have shown that vitamin D can improve dyslipidemia by stimulating calcium absorption in the small intestine, thus lowering both TG production and saturated fatty acids absorption.[44] Furthermore, VDR overexpression reduces lipid catabolism, promotes lipogenesis pathways, and improves adipocyte differentiation and proliferation.[45]