Lower circulating α-Klotho levels were observed in individuals with osteoporosis compared with those with normal BMD (95% CI: - 114.98, - 25.49; p = 0.002) and in individuals with osteopenia compared with those with normal BMD (95% CI: - 123.22, - 0.74; p = 0.05), and were associated with fractures. Here, KL is linked to osteoporosis.