What Causes Osteoporosis?

What Causes Osteoporosis?

Our bones are constantly being rebuilt throughout our lifetime. Bones are made up of collagen, a protein that provides the basic framework, and calcium phosphate, a mineral that hardens the bone. As we age, we lose more bone than we replace. The greatest change in a woman's bone density comes in the five to seven years after menopause.
The green, oblong shape in the illustration is an osteoclast, a cell that breaks down bone.