A method of preventing or treating ionizing radiation-associated loss of bone mass, bone density or bone strength in a subject is provided, comprising administering to the subject an amount of an antiresorptive or osteoclast inhibiting compound sufficient to prevent or mitigate loss of bone mass, density or strength. A method of preventing or treating radiation-associated increase in the number or activity of osteoclasts in a subject is also provided, comprising administering to the subject an amount of an antiresorptive compound sufficient to reduce osteoclast numbers or reduce osteoclast activity and prevent resulting loss of bone mass, density or strength.