Risk Factors:

Gender

About 10 million adults in the United States have osteoporosis and another 34 million have low bone mass that places them at risk for developing osteoporosis. According to a report from the Surgeon General's office, by 2020 half of all Americans over age 50 could be at risk for this condition. Seventy percent of people with osteoporosis are women. Men start with higher bone density and lose calcium at a slower rate than women, which is why their risk is lower. Nevertheless, older men are also at risk for osteoporosis.

Age

As people age, their risks for osteoporosis increase. Aging causes bones to thin and weaken.

Ethnicity

Although adults from all ethnic groups are susceptible to developing osteoporosis, Caucasian and Asian women and men face a comparatively greater risk.

Body Type

Osteoporosis is more common in people who have a small, thin body frame and bone structure.

Family History

People whose parents had a history of fractures may be more likely to have fractures.

Hormonal Deficiencies

Women. Events associated with estrogen deficiencies are the primary risk factors for osteoporosis in women. These include:

• Menopause. Within 5 years after menopause, the risk for fracture increases dramatically. Fractures occurring during this period are more likely to occur in the wrist or spine than the hip, but their occurrence is a strong predictor of later severe osteoporosis and hip fracture.
• Surgical removal of ovaries
• Missing periods for 3 months or longer
• Never having given birth
• Anorexia nervosa, (an eating disorder), or extreme low body weight can affect the bodyâ ' s production of estrogen

Men. Low levels of testosterone increase osteoporosis risk. Certain types of medical conditions (hypogonadism) and treatments (prostate cancer androgen deprivation) can cause testosterone deficiency.

Lifestyle Factors

Dietary Factors. Diet plays an important role in preventing and speeding up bone loss in men and women. Calcium and vitamin D deficiencies are important factors in the risk for osteoporosis. Other dietary factors may also be harmful or protective for certain people.

Calcium requires adequate vitamin D in order to be absorbed by the body. In the United States, many food sources of calcium such as milk are fortified with vitamin D.

Exercise. Lack of exercise and a sedentary lifestyle increases the risk for osteoporosis. Conversely, in competitive female athletes, excessive exercise may reduce estrogen levels, causing bone loss. (The eating disorder anorexia nervosa can have a similar effect.)

Lack of Sunlight. The photochemical effect of sunlight on the skin is a primary source for vitamin D. Bone formation peaks in the summer and bone breakdown increases in the winter. People who avoid sun exposure to prevent skin cancer may be at risk for vitamin D deficiency, particularly if they are elderly.

Smoking. Women who smoke, particularly after menopause, have a significantly greater chance of spine and hip fractures than those who donâ ' t smoke. Men who smoke also have lower bone density.

Alcohol. Excessive consumption of alcoholic beverages can increase the risk for bone loss.

Risk Factors in Children and Adolescents

The maximum density that bones achieve during the growing years is a major factor in whether a person goes on to develop osteoporosis. Persons, usually women, who never develop peak bone mass in early life are at high risk for osteoporosis later on. Children at risk for low peak bone mass include children who are:

• Born prematurely
• Have anorexia nervosa
• Have delayed puberty or abnormal absence of menstrual periods

Although to a large extent genetics predict bone health, exercise and good nutrition during the first three decades of life (when peak bone mass is reached) are still excellent safeguards against osteoporosis (and countless other health problems).