What is more, Gabbay et al. [11], Aliabri et al. [12] and Panjiyar et al. [10] have revealed the favorable effect of optimal vitamin D level in patients with T1DM on metabolic control of the disease evaluated by glycated hemoglobin level (HbA1c), C-peptide concentration, insulin sensitivity and reduction of total daily dose of insulin. Here, INS is linked to type 1 diabetes mellitus.