Illustration suggesting osteoporosis. The visual metaphor of a deteriorating, classical Roman column is used to suggest osteoporotic changes to a structural element. Osteoporosis is the loss, over time, of bone density. A loss in bone density is commonly associated with changes women experience during menopause as the decreased hormonal levels affect the calcium balance in the blood, and bone mass is lost as a result. Loss of bone density in often results in compression fractures. Depicted here are normal, moderately osteoporotic, and severely osteoporotic cancellous vertebral bone.