Serum 25(OH) vitamin D3 concentrations inversely correlated with FBG (Pearson’s coefficient: -0.26, p<0.007) serum phosphate (Pearson’s coefficient: −0.21, p<0.03) and PTH levels (Pearson’s coefficient: −0.28, p<0.003) but were not associated with anthropometrical parameters, fat mass percentage, the diagnosis of T2D and insulin resistance indexes in the univariate analysis. Here, PTH is linked to Insulin resistance.