During childhood and teen years, new bone grows faster than existing bone is absorbed by the body. After age 30, this process begins to reverse. As a natural part of aging, bone dissolves and is absorbed faster than new bone is made, and bones become thinner. You are more likely to have osteoporosis if you did not reach your ideal bone thickness (bone density) during your childhood and teenage years.
In women, bone loss increases around menopause, when ovaries produce less estrogen, a hormone that protects against bone loss. Younger women, especially in their 30s and 40s, are at lower risk for osteoporosis than older women. But your risk increases if you:
Have already gone through menopause. Most women go through menopause starting in their 50s, but some women go through this change earlier.