HAMP and osteoporosis: With regard to osteoporosis and markers of bone metabolism, the serum iron level was positively related to femoral T and Z scores (r = 0.230, p < 0.001 and r = 0.150, p = 0.015, respectively), and ferritin and hepcidin levels were positively related to the 25(OH)D level (r = 0.250, p < 0.001 and r = 0.193, p = 0.002, respectively) (Table 2 and Fig. 2).