Bone metabolic markers including type I collagen, osteocalcin, PTH, 25(OH)VD, and total calcium between genders had no difference (all p > 0.05) while calcitonin was significantly higher in men than in women with T2DM (12.00 (6.00, 19.25) vs. 9.00 (4.00, 17.00), p < 0.001). Here, CALCA is linked to type 2 diabetes mellitus.