A fracture can result from minimal or no trauma. Osteoporosis is not a natural part of aging and does not occur all over the world. The U.S. has the highest osteoporosis rate in the world. We're not alone, however, as most highly industrialized societies report much higher rates of osteoporosis than less industrialized ones. Exposure to sunlight, produces vitamin D which is essential for calcium absorption and thus healthy bones.
Women are less physically active and are discouraged from developing a strong muscular structure.
Where we find increased muscle mass we find stronger bones. Women use more prescription drugs, and are more subject to surgery of the sex glands than men. Sex hormones produced by the ovaries play a very important role in the maintenance of healthy bone, before and after menopause. Each year over 500,000 women lose their ovaries in surgery, most in total hysterectomies. At least half will suffer early and excessive bone loss.