An individual’s risk for the development of osteoporosis depends on how much bone mass has been attained by age 25 to 35 (peak bone mass) and how rapidly it is lost afterward.

The higher the peak bone mass, the more bone a person has “in the bank” and the less likely that person is to develop osteoporosis as bone is lost during normal aging or during menopause.

The decrease in bone mass and the microscopic deterioration of the skeleton can lead to an increased risk of bone fragility and fractures, back pain, and a loss of height. The most common fractures resulting from osteoporosis include vertebra, hip, forearm, and wrist.

Fractures can also easily occur in other bones. Fractures can severely compromise lifestyle and limit mobility. If an older woman breaks a hip, for instance, she has only a 25 percent chance of ever resuming her former level of physical activity.

A broken hip can easily be the end of an independent way of living or even contribute to an early death from complications of operation or immobilization. Once you have had a fracture, there is an increased risk of having another.

Although osteoporosis generally is considered a disease that plagues elderly women, it can begin in others in their 40s and 50s. This potential crippler affects 8 to 10 million American women and about 2 million older American men.

The cost of osteoporosis to the American economy is about $13 billion per year. Given current aging trends, these costs will increase dramatically in the coming decades.

Physicians can detect early signs of osteoporosis with a simple, painless bone density test. This test uses x-ray or ultrasound technology to measure bone density at likely sites for fractures.

The test also can predict the risk of future fractures. Measuring bone density helps identify individuals who have osteoporosis or the threat of osteoporosis. In addition, other tests for osteoporosis are being developed and tested.

Although osteoporosis may not be fully preventable, researchers are agreeing that the following steps can delay its onset or improve the treatment outlook and thereby the quality of life.

• Maximal Bone Mass - Building maximal bone mass will make bone fractures later in life less likely. Maximal bone density depends partly on the inherited ability to make bone, the amount of calcium consumed, and the level of exercise.

• Estrogen Replacement Therapy - Estrogen replacement therapy is the single most important way for women to reduce their risk for osteoporosis during and after menopause, provided there is understanding of the risks and benefits of this type of therapy and it is closely monitored by a physician.

Estrogen receptors are present in bone, and estrogen inhibits bone breakdown. Estrogen replacement therapy can decrease or prevent bone loss and reduce the risk of spine and hip fractures by as much as 50 percent.

For women who already have osteoporosis (and who have no conditions prohibiting the use of estrogen), starting estrogen replacement therapy can increase bone density by as much as 10 percent in the spine and 5 percent in the hip.

However, there are some risks associated with estrogen replacement therapy. Taking estrogen alone, without its natural balancing hormone progesterone, increases the risk of cancer of the uterus. And there may be a small increase in the risk of breast cancer from long-term use of estrogen.

However, estrogen treatment may help decrease the risk of heart disease in certain groups and may also decrease the risk of other diseases, such as dementia. Women who have breast or uterine cancer, uncontrolled high blood pressure, or a tendency to form blood clots should avoid estrogen.

If blood triglyceride levels are high, women should consult their physicians to see if an alternative form of estrogen is an option. There are new types of estrogen (estrogen analogs) that may prevent or slow the rate of bone loss without the increased risk of breast cancer.

However, these drugs may not be as effective as estrogen and may not have all of the beneficial effects. In addition to estrogen and estrogen analogs, other types of medications are available and new ones are under development to prevent and treat osteoporosis.

• Calcium and Vitamin D - Adequate amounts of calcium and vitamin D are critical for building peak bone mass in younger years and for slowing bone loss in later years. Calcium is a vital mineral in the body. In addition to being one of the essential building blocks of bone, calcium is essential to the function of the muscles (including the heart) and the function of the nerves, and it helps the blood to clot in case of injury.

If people fail to get enough calcium in their diets, their bodies will take calcium from the bones to keep the blood calcium level constant. Recommendations for calcium vary a bit according to age and medical status. For ages 9 to 18, 1,300 milligrams of calcium daily is recommended.

For ages 19 to 50, the recommendation is 1,000 milligrams. Finally, for ages 51 or older, 1,200 milligrams is recommended. During pregnancy and lactation, the recommendation is 1,300 milligrams. The richest dietary sources of calcium are milk, cheese, and yogurt.

Other sources of calcium are broccoli, turnip greens, canned fish with bones, and calcium-fortified orange juice and tofu. Of course, if you are trying to get extra calcium through your diet, you should monitor your weight; foods such as whole milk, certain cheeses, and ice cream are rich in calories and fat.

Depending on dietary choices and habits, food alone can provide the recommended amounts of calcium. If you are unsure of the calcium content of foods, follow this simple formula for estimating intake of dietary calcium: assign approximately 300 milligrams for the baseline diet, and add 300 milligrams for each serving of a dairy product (cup or slice) and 160 milligrams for each serving of a calcium-fortified food that you eat.

If your diet is not adequate in calcium, a supplement may be indicated. Dietary absorption of calcium can be assessed by your physician. A 24-hour urine collection can measure the calcium content to determine how well or how poorly calcium is being absorbed from your diet.

Vitamin D helps the body absorb and metabolize calcium and deposit it in the bones. People can get vitamin D from vitamin D-fortified milk, liver, fish, egg yolks, and exposure to sunshine.

Getting 10 to 15 minutes of midday sun 2 or 3 times a week can provide sufficient vitamin D—although not from a winter sun in a northern climate. Older adults or persons with certain diseases often benefit from a supplement. A multivitamin pill with 400 international units of vitamin D provides an adequate amount.

• Caffeine - Limiting caffeine is a prudent idea. Too much caffeine can cause extra calcium to be lost in the urine. If an individual has only 2 or 3 cups of coffee a day and is consuming enough calcium in the diet, there should be no problem.

• Alcohol - Consuming more than 2 drinks a day can inhibit bone formation and interfere with calcium absorption.

• Smoking - Smoking decreases your body’s ability to form healthy bones.

• Weight-Bearing Exercise - Weight-bearing exercise is any activity done while the bones are supporting the body’s weight. It can slow bone loss, strengthen the bones and back, improve posture, and aid in balance, which helps prevent falls.

Exercises in which bone sustains repeated impact have added benefit because, for example, the leg bones respond to the impact of the feet striking the ground by slowing bone loss. Remember, it is never too late to begin an exercise program.

Bone-building exercises for prevention of osteoporosis include walking, jogging, running, stair climbing, skiing, and impact-producing sports. Because strong muscles exert more force, and bones respond by becoming stronger, weight lifting (or strength training) is another excellent way to forestall osteoporosis.

Of course, anyone with osteoporosis may benefit by consulting with a physician to design a safe exercise program.

• Trauma - Avoiding trauma is a given at any stage of life, but even more so for persons with osteoporosis. Wear sturdy, lowheeled shoes with nonslip soles, and check your home for potential obstacles that could cause a fall, such as low tables, loose rugs, or inadequate lighting. The broken bones that come from tumbles and falls can produce serious, even life-threatening, medical complications.