Knowledge of the underlying mechanisms of osteoporosis in older adults has significantly advanced in recent years. There is an acute loss of bone mineral density in the peri-menopausal period, followed by a more gradual and progressive decline, which is also seen in men. Markedly increased bone resorption leads to the initial fall in bone mineral density. With increasing age, there is also a significant reduction in bone formation. This is mostly due to a shift from osteoblastogenesis to predominant adipogenesis in the bone marrow. This study reviews new evidence on the pathophysiology of senile osteoporosis, with emphasis upon the mechanism of action of current osteoporosis treatments. New potential treatments are also considered, including therapeutic approaches to osteoporosis in elderly people that focus on the pathophysiology and potential reversal of the adipogenic shift in bone.