This condition develops without warning signs. Most people with osteoporosis do not realize they have the disease until a minor fall results in a broken hip, wrist, or vertebra. Bone Remodeling Calcium, phosphate, and collagen are the primary components of bone. Bone tissue is constantly changing. Cells called osteoclasts break down and remove bone tissue in the process of resorption .
Osteoblasts form new bone in a process called formation .
During childhood and early adulthood, bone formation exceeds bone resorption. By age 35, men and women reach and maintain maximum bone density and strength, called peak bone mass . After the age of 40 or so, resorption exceeds formation, and gradual bone loss begins. In menopausal women in their fifties, bone loss increases rapidly. During menopause, estrogen production decreases, which increases the rate of bone resorption.