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Osteoporosis - overview

Alternative Names:

Thin bones; Low bone density; Metabolic bone disease


Osteoporosis is the most common type of bone disease.

Osteoporosis increases the risk of breaking a bone. About half of all women over the age of 50 will have a fracture of the hip, wrist, or vertebra (bones of the spine) during their lifetime. Spine fractures are the most common.

Your body needs the minerals calcium and phosphate to make and keep healthy bones.

  • During your life, your body continues to both reabsorb old bone and create new bone.
  • As long as your body has a good balance of new and old bone, your bones stay healthy and strong.
  • Bone loss occurs when more old bone is reabsorbed than new bone is created.

Sometimes, bone loss occurs without any known cause. Other times, bone loss and thin bones run in families. In general, white, elderly women are the most likely to have bone loss.

Brittle, fragile bones can be caused by anything that makes your body destroy too much bone, or keeps your body from making enough new bone. As you age, your body may reabsorb calcium and phosphate from your bones instead of keeping these minerals in your bones. This makes your bones weaker.


A major risk is not having enough calcium to build new bone tissue. It is important to eat enough high-calcium foods. You also need vitamin D, since it helps your body absorb calcium. Your bones may become brittle and more likely to fracture if:

  • If you do not eat enough food with calcium and vitamin D
  • Your body does not absorb enough calcium from your food, such as after gastric bypass surgery

Other causes of bone loss include:

  • A decrease in estrogen in women at the time of menopause and a decrease in testosterone in men as they age.
  • Being confined to a bed due to a prolonged illness (mostly affects bone in children)
  • Having certain medical conditions that cause increased inflammation in the body
  • Taking certain medicines, such as certain seizure medicines, hormone treatments for prostate or breast cancer, and steroid medicines taken for more than 3 months

Other risk factors include:

  • Absence of menstrual periods for long periods of time
  • A family history of osteoporosis
  • Drinking a large amount of alcohol
  • Low body weight
  • Smoking
  • Having an eating disorder, such as anorexia nervosa
Osteoporosis is a rare disease of the bones.The correct answer is myth. Osteoporosis is the most common type of bone disease. People with osteoporosis develop weak bones that can break easily. Finding and treating osteoporosis early before bones become too weak can help prevent breaks.Osteoporosis develops when:The correct answer is both. Even though bones are hard, they are living tissue. The body is constantly building new bone tissue to replace the bone tissue it uses up. If it can't do this fast enough, the bones become weak and brittle. Aging, too little calcium, or certain health problems can cause bone loss. In the early stages, a common sign of osteoporosis is:The correct answer is none of the above. There are no symptoms in the early stages of osteoporosis. Many times, a bone break is the first sign of the disease. This is why people at risk should be tested for osteoporosis. Ask your doctor about your risk for osteoporosis.Osteoporosis often causes fractures of the:The correct answer is all of the above. About half of all women over the age of 50 will have a fracture of the hip, wrist, or vertebra during their lifetime because of bone loss. Menopause is a good time to talk with your doctor about your risk of osteoporosis and how to reduce it.Osteoporosis can make you shorter.The correct answer is fact. Over time, osteoporosis can cause many small breaks along the spine. These breaks in the vertebrae can gradually cause back pain, stooped posture, and a loss of up to 6 inches of height. Your doctor can detect these breaks with an x-ray of the spine.The best osteoporosis screening measures the amount of bone in the:The correct answer is lower spine and hip. Your doctor uses a type of X-ray machine to test you for osteoporosis. You might see small X-ray machines in pharmacies or at health fairs. They can measure bones in the finger, wrist, leg, or heel, but are not as accurate as the X-ray machine your doctor uses.Which lifestyle change can help prevent and treat osteoporosis?The correct answer is all of the above. Your body needs calcium to build bone. To build strong bones, you should get enough calcium in your diet starting in childhood or early adulthood. Dairy products have the most calcium. Smoking and alcohol use reduces bone strength. Talk with your doctor about how to prevent osteoporosis. Osteoporosis medicines can reduce the risk of fractures.The correct answer is fact. Bisphosphonates (Fosamax, Boniva, Actonel , or Reclast) are used to prevent and treat bone loss. They help make the bones in your hips, spine, and other areas stronger. You may take a pill weekly or monthly or have an IV infusion once a year. Talk with your doctor about the pros and cons of this medicine.Your doctor will prescribe medicine only if you already have osteoporosis.The correct answer is false. Your doctor may also prescribe medicine if you have had a bone fracture and a bone test shows your bones are thinner than normal bones. The goal is to prevent another bone fracture by building up your bones.To reduce the risk of falls, people with osteoporosis should:The correct answer is all of the above. Hip fractures are one of the main reasons people have to go into nursing homes. If you have osteoporosis, and even if you don’t, avoiding falls and fractures can help you stay independent. Talk with your doctor about other ways to prevent falls.

There are no symptoms in the early stages of osteoporosis. Many times, people will have a fracture before learning they have the disease.

Fractures of the bones of the spine can cause pain almost anywhere in the spine. These are called compression fractures. They often occur without an injury. The pain occurs suddenly or slowly over time.

There can be a loss of height (as much as 6 inches) over time. A stooped posture or a condition called a dowager's hump may develop.

Exams and Tests:

A DEXA scan is a low-radiation x-ray that measures the density of the minerals in your bones. Usually, it measures density in the spine and hip bones. Your health care provider uses this test to:

  • Diagnose bone loss and osteoporosis
  • Predict your risk of future bone fractures
  • See how well osteoporosis medicine is working

A simple spine or hip x-ray may show fracture or collapse of the spinal bones. However, simple x-rays of other bones are not very accurate in predicting whether you are likely to have osteoporosis. A new low-radiation spine x-ray called a vertebral fracture assessment (VFA) is now often done with a DEXA to better identify fractures that do not have any symptoms.

You may need blood and urine tests if your provider thinks the cause of your osteoporosis is a medical condition, rather than the slow bone loss that occurs with aging.

DEXA scan results compare your bone mineral density with both a young adult who has no bone loss and with people your age and gender. This means that at age 80, almost one third of women with normal age-related bone loss would have osteoporosis, based on their DEXA scan results.

Outlook (Prognosis):

Medicines to treat osteoporosis can help prevent future fractures. But spine bones that have already collapsed cannot be made stronger.

Osteoporosis can cause a person to become disabled from weakened bones. Hip fractures are one of the main reasons people are admitted to nursing homes.


Be sure you get enough calcium and vitamin D to build and maintain healthy bone. Following a healthy, well-balanced diet can help you get these and other important nutrients.

Other tips for prevention:

  • Do not drink large amounts of alcohol.
  • Do not smoke.
  • Get regular exercise.

Medicines can treat osteoporosis and prevent fractures. Your doctor can tell you if any are right for you.


Lewiecki EM. In the clinic. Osteoporosis. Ann Intern Med. 2011;155(1):ITC1-1-15;quiz ITC1-16.

Lorenzo JA, Canalis E, Raisz LG. Metabolic bone disease. In: Melmed S, Polonsky KS, Larsen PR, Kronenberg HM, eds. Williams Textbook of Endocrinology. 12th ed. Philadelphia, PA: Elsevier Saunders; 2011:chap 29.

Moyer VA; U.S. Preventive Services Task Force. Vitamin D and calcium supplementation to prevent fractures in adults: U.S. Preventive Services Task Force recommendation statement. Ann Intern Med. 2013 May 7;158(9):691-6.

The National Osteoporosis Foundation (NOF) Clinician's Guide to prevention and treatment of osteoporosis. National Osteoporosis Foundation, Washington, DC. 2013.

North American Menopause Society. Management of osteoporosis in postmenopausal women: 2010 position statement of The North American Menopause Society. Menopause. 2010 Jan-Feb;17(1):25-54.

Park-Wyllie LY, Mamdani MM, Juurlink DN, Hawker GA, Gunraj N, Austin PC, et al. Bisphosphonate use and the risk of subtrochanteric or femoral shaft fractures in older women. JAMA. 2011;305(8):783-789.

Rosen C. Osteoporosis. In: Goldman L, Schafer AI, eds. Goldman's Cecil Medicine. 24th ed. Philadelphia, PA: Elsevier Saunders; 2011:chap 251.

Review Date: 10/25/2014
Reviewed By: Brent Wisse, MD, Associate Professor of Medicine, Division of Metabolism, Endocrinology & Nutrition, University of Washington School of Medicine, Seattle, WA. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.

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