Table 1. Summary of the effect of Vitamin D supplement on various tissues/organs in Diabetes Mellitus II patients.

VDR - Vitamin D receptor; HbA1c - Hemoglobin A1c

Organs/Cellular Processes/ Tissues	Effect of Vitamin D
Pancreas	Increases insulin secretion through its activation in pancreatic B cells, enhances the transformation of pro-insulin into insulin.
Fatty acids	It enhances fatty acid oxidation, decreasing insulin resistance.
Skeletal Muscles	Through the expression of VDR in skeletal muscles, it is supposed to have a role in glucose hemostasis.
Kidney	Decreases urinary albuminuria.
Nervous system	Improves nerve conduction. Potent analgesic effect.
Skin	Improves wound healing through improving skin microcirculation.
Hemoglobin A1c (HbA1c)	Decreases HbA1c.
Retina	Protective against oxidative stress.