Bone mass Bone mass increases from childhood to about the age 35, where it peaks and gradually begins to diminish, causing bones to become less dense. About half of bone mass is lost before menopause. Deficiency of estrogen, progesterone, testosterone, growth hormone and vitamin D also reduce bone density. Genetic factors also play a major role. Since low bone mass is defined as 1SD to 2.5 SD below normal, it means 2 to 5 times higher risk of fracture, which means that almost 34 million women and men over 50 are at increased risk of fracture.
Fractures are more prevalent in whites than in blacks and in women than in men.
But there is another cost as well - human lives. Increased mortality remains high for several years after a fracture. But even if you survive a hip fracture, you are not home free. This pain is due to micro-fractures. Unfortunately, most women and men realize they suffer from osteoporosis only when a fracture occurs.