Bone is living, growing tissue. It is made mostly of collagen, a protein that provides a soft framework, and calcium phosphate, which adds strength. This combination makes bones strong yet flexible enough to withstand stress.
FIGURE 7-13 Osteoporosis—sites of fractures.
Reprinted with permission from National Osteoporosis Foundation, Washington, D.C., 20037.
Throughout your life, old bone is removed (called resorption) and new bone is added to the skeleton. During childhood and the teenage years, new bone is added faster than old bone is removed. As a result, bones become larger, heavier, and denser. Bone formation continues at a pace faster than resorption until peak bone mass (maximum bone density and strength) is reached at around age 30. After age 30, bone resorption slowly begins to exceed bone formation.
Bone loss is most rapid in the first few years after menopause but persists into the postmenopausal years. Osteoporosis is more likely to develop if you did not reach optimal bone mass during your bone-building years.
Was this article helpful?