Osteoporosis prevention relies on a three-pronged approach of exercise, proper nutrition, and—when appropriate—medication, including some bisphosphonates. While women are more likely than men to develop osteoporosis, men, too, should get regular exercise, eat well, and minimize other risk factors.
Exercise is an important component of osteoporosis prevention. The more active you are, the stronger your bones will be. Certain types of exercise are more beneficial than others for preventing osteoporosis. Your exercise routine should include weight-bearing and resistance exercises and ideally should begin well before menopause. Older people should incorporate balance exercises into their routine.
Although calcium is in the nutritional spotlight for its role in preventing osteoporosis, vitamin D also is essential. A number of other nutrients provided by a well-rounded, healthy diet play a role in building healthy bone as well. But some researchers are re-evaluating the role of a high-protein diet for osteoporosis prevention.
For men and women age 19 to 50, the recommended daily intake (Dietary Reference Intake, or DRI) for calcium is 1,000 mg per day. After age 50, the DRI increases to 1,200 mg per day.
The best sources of calcium are low-fat milk and other dairy products. For example, one cup of milk contains 300 mg of calcium, and one cup of plain, low-fat yogurt contains 415 mg. Low-fat dairy products contain slightly more calcium than their full-fat counterparts—low-fat milk actually contains slightly more than 300 mg of calcium per cup, while full-fat milk contains slightly less. But the real reason to choose low-fat products is to avoid excessive intake of saturated fat.
If you have lactose intolerance (an inability to digest the naturally occurring sugars in milk) and dairy foods give you digestive problems, you will need to include other sources of calcium in your diet such as canned salmon with bones (3 oz contains 200 mg of calcium), leafy green vegetables, almonds, calcium-fortified cereals, and calcium-fortified orange juice.
Despite these dietary sources of calcium, surveys show that most people get less than the DRI for calcium from their diet. In fact, a dietary intake of only 400 mg of calcium per day is quite common. Although meeting the DRI is possible with careful dietary planning, most people need to take daily supplements that provide an additional 500 to 1,000 mg of calcium.
A variety of calcium supplements are available. Calcium carbon- ate and calcium citrate contain the highest percentage of calcium in each tablet, but calcium citrate is more readily absorbed from the intestine. You should take calcium carbonate pills with meals because this type of calcium is absorbed better in the presence of stomach acid.
Many individuals fail to consume a sufficient amount of vitamin D each day. A recent study found that women with low blood levels of vitamin D were at increased risk for hip fracture. Without vitamin D, the body cannot absorb calcium properly.
A number of studies have confirmed that vitamin D intake helps prevent osteoporosis and lower the risk of fractures in older adults. Vitamin D not only helps with the absorption of calcium, but also aids in the biochemical process by which calcium turns into bone.
Most vitamin D is synthesized by the skin in response to sunlight. In nature, very few foods contain vitamin D. While some foods are fortified—especially breakfast cereals and milk products—studies have shown that the amount listed on the label does not always reflect the contents accurately.
The National Osteoporosis Foundation recommends that women and men under age 50 consume 400 to 800 IU of vitamin D per day. For people age 50 and over, 800 to 1,000 IU daily is recommended.
A healthy diet rich in fruits and vegetables will provide plenty of phos- phorus, magnesium, and vitamins C and K, all of which play a role in bone health.
Vitamin A Caution
If you take a daily multivitamin, choose one that contains no more than 900 micrograms (mcg) of vitamin A for men and 700 mcg for women. Also make sure that at least 20% of its vitamin A is in the form of beta-carotene. Research suggests that a high intake of vita- min A from retinol might increase the risk of hip fractures in post- menopausal women; too much vitamin A has also been associated with fractures in men.
Hormone Replacement Therapy (HRT)
The hormone estrogen stimulates the bone-building ability of osteoblasts and suppresses the bone-destroying activity of osteoclasts. At menopause, when estrogen levels fall, women suddenly experience a rapid loss of bone and an increased risk of fractures.
Hormone replacement therapy (HRT) involves taking estrogen to treat menopausal symptoms, such as hot flashes, night sweats, and vaginal dryness. The most common HRT formulation also contains a synthetic form of progesterone to counteract the increased risk of uterine cancer in women who take estrogen alone. Women who have had a hysterectomy are able to take estrogen without progesterone.
In addition to easing the symptoms of menopause, HRT reduces the rapid loss of bone that accompanies it. The sooner HRT begins after menopause, the greater the preservation of bone.
The decision to use HRT should not be taken lightly. One of the most common forms of HRT, conjugated equine estrogen plus medroxyprogesterone (Prempro), has been found to increase the risk of breast cancer and cardiovascular events (such as heart attacks, strokes, and blood clots) when taken for several years. For this reason, women should not take HRT for any longer than needed to treat menopausal symptoms. If a woman is concerned about bone loss and thinking about HRT, she should discuss her personal risk and benefit profile with her doctor. Despite the fact that HRT continues to be recommended for preventing osteoporosis, other drugs are available that can accomplish the same goal.
One final note: As soon as a woman stops taking HRT, bone loss will begin again. Thus, it is important to assess the need for osteoporosis treatment before discontinuing HRT.
Testosterone in Men
Men with abnormally low levels of testosterone, which can cause osteoporosis, can take testosterone replacement therapy to help preserve their bones.
Because the prolonged use of corticosteroids, such as prednisone, can result in significant reductions in bone mass, the American College of Rheumatology (ACR) has issued guidelines for preventing osteoporosis in people taking them. Because prednisone dosages as low as 7.5 mg per day can result in bone loss and an increased risk of fractures, the lowest effective dose should always be used. Corticosteroid formulations that are applied to the skin or inhaled cause fewer side effects than those taken orally, yet they still can have deleterious effects on the skeleton.
The ACR guidelines recommend getting a BMD measurement when beginning steroid therapy (or as soon as possible thereafter) and at periodic intervals throughout treatment, following the lifestyle recommendations, and possibly using one of the medications discussed below.
These recommendations are based on 10-year fracture risk as calculated using the FRAX tool (http://www.sheffield.ac.uk/FRAX). If FRAX calculates that your 10-year risk of a major osteoporotic fracture is less than 10 percent, you are considered to be at low risk; if it is between 10 and 20 percent, you are at medium risk; and greater than 20 percent is considered high risk.
For postmenopausal women or men age 50 or older who are at:
Low risk. The ACR guidelines recommend preventive treatment with alendronate (Fosamax), risedronate (Actonel), or zoledronic acid (Reclast) if 7.5 mg or more of prednisone is to be used daily for at least three months.
Medium risk. Fosamax or Actonel is recommended if a corticosteroid is used for at least three months, regardless of the dosage. If the daily dosage of predisone is 7.5 mg or higher, treatment with Reclast is recommended.
High risk. The recommended medication is Fosamax, Actonel, or Reclast regardless of the steroid dosage if it is used for one month or less. If more than 5 mg of prednisone is used daily for less than one month or any dosage of steroids is used for more than a month, Fosa- max, Actonel, Reclast, or teriparatide (Forteo) may be used.
The guidelines also recommend extra calcium for corticosteroid users—a total of 1,500 mg a day—and 800 to 1,000 IU of vitamin D.