INS and metabolic syndrome: Furthermore, a study including individuals with metabolic syndrome and T2DM who were given 1,25(OH)2D3 as a supplement revealed that vitamin D effectively reduced oxidative DNA damage and increased insulin sensitivity, as seen by a decline in the HOMA-IR (homeostatic model assessment for insulin resistance) and TG/HDL ratio (triglyceride (TG) to high-density lipoprotein (HDL) [168].