The number of people with osteoporosis in the United States, as well as around the world, is rising rapidly. Although there are many reasons for this increase, one important cause is the dramatic rise in our life expectancy. Osteoporosis currently affects 10 to 12 million Americans and another 28 to 32 million have osteopenia, or low bone mass. As the population ages, we expect that the number of people with osteoporosis will increase exponentially during the first half of this century.
Bone strength depends on the amount of bone present and the quality of the bone. Both decrease as you age. A bone density scan can measure how much bone is present, but it can’t measure the quality of the bone. In post-menopausal women and men over age 50, currently the best method to measure bone mineral density (BMD) is with a dual energy X-ray absorptiometry (DXA).
Bone fractures are the main clinical symptom of osteoporosis. Half of all women over age 50 will suffer a bone fracture during their lifetime. We expect the increase in the number of people with osteoporosis to lead to a tripling of the number of hip fractures by 2040. Broken bones can be very painful and disabling and can lead to loss of independence for older men and women.
Fortunately, medical researchers have learned a huge amount about how to diagnose, prevent and treat osteoporosis. Many of the fractures that plague older Americans could be prevented, if the disease was detected and treated early enough.
Here are some characteristics to determine whether you are at risk for developing osteoporosis:
- Gender: Women are much more prone to fractures than men. Eighty percent of osteoporosis fractures occur in women; 20 percent in men.
- Age: The vast majority of fractures occur after the age of 60.
- Family history: If your grandparents or parents broke a wrist, arm, or hip, or their spine looked hunched, when they got older, your risk of osteoporosis is increased.
- History of fracture after 50: If you are over age 50 and have already had a fracture, your risk of having more fractures is much higher.
- Body weight: Weighing less than 127 pounds (for women) increases your risk, while being significantly overweight decreases your risk.
- Bone structure: Larger bones are stronger than small bones — so petite women are at increased risk for osteoporosis.
- Early menopause: Lack of estrogen promotes bone loss. If your menopause occurred before age 45, or if you lost your periods for more than 6 months but were not pregnant, your bone density may be lower than normal.
- Medications: Many medications cause bone loss. The most common one is prednisone. Others include aromastase inhibitors (used to treat women with breast cancer), drugs containing the thyroid hormone and some drugs used to treat seizures or convulsions.
- Diseases: Many diseases cause bone loss. Some common ones are rheumatoid arthritis and celiac disease.
- Lifestyle: Lack of calcium in your diet can lead to bone loss. This is common.
- Vitamin D: This vitamin is made by the action of the sunshine on your skin and is very important to maintain bone health. Vitamin D deficiency is very common.
- Lack of exercise: A sedentary lifestyle can lead to excess bone loss.
- Cigarettes and alcohol: Smoking and excessive drinking can both affect the cells that make new bone. Both can increase your risk for bone loss.
- Propensity to fall: As we get older our balance is less good and we fall more easily. Most broken bones happen when we fall down, so if you tend to fall over a lot, you may be more likely to have a bone fracture.
Here are some tips on how you can maintain good bone health:
- Include calcium in your diet: Postmenopausal women need about 1,000 to 1,200 milligrams a day, approximately the amount in three to four eight-ounce glasses of skim milk, or three cups of yogurt. In general, food sources of calcium are best, but if you can’t take in enough that way, take a calcium supplement to make up the rest.
- Take vitamin D: Everyone should take a daily vitamin pill that contains at least 400 units of vitamin D. Many experts think that more vitamin D is necessary. In general up to 1,000 units a day is safe. Don’t take more without telling your doctor. He or she can check a blood test to make sure you are getting the right amount.
- Exercise: Try and walk for 30 minutes each day.
- Don't smoke: Smoking is bad for everything you can think of!
- Drink alcohol only in moderation: One drink a day should be the limit on average.
- Eliminate fall hazards: Look around your house with an eye to prevent falls. Remove small area rugs. Install railings on all stairs and in the bathtub. Make sure your home is well lighted. Don’t go out on icy days.
- If necessary, your doctor may recommend medication to prevent you from having fractures.
Here are some helpful resources:
- The National Osteoporosis Foundation is an excellent source for additional information about osteoporosis and bone health. For more information, click here.
- The American Society for Bone and Mineral Research also supports a Web site maintained by Dr. Susan Ott at the University of Washington in Seattle. This site has more detailed medical information and is also an excellent resource. For more information, click here.
Elizabeth Shane, M.D. is a professor of medicine at Columbia University’s New York Presbyterian Medical Center.