Bone Density and Healthy Aging
From time to time, your doctor may recommend a “bone density test,” designed to tell you and your physician about how strong your bones are. This is an important test because a low score can mean that you are more likely to experience major bone fractures, which can lead to disability. So, if your doctor recommends the test, you should take the advice. The test is painless and relatively inexpensive.
What Causes Low Bone Density?
Bone is a living tissue like other tissues and organs. Changes in metabolism can create changes in bone mass. The bones of the spine and wrist are particularly susceptible to changes in metabolism and, therefore, changes in bone mass. All bone, however, is subject to depletion of calcium, which can lead to low bone mass and the possibility of fractures.
Normal calcium intake and exposure to Vitamin D often create healthy bone tissue until people peak at age 30. Then, people begin to lose bone density; by age 50, it can become problematic. Osteoporosis — a term used to describe the loss of normal bone matrix — is common and is estimated to afflict approximately 40 million Americans.
Particularly during the first five years following menopause, women are more susceptible to loss of bone density. However, all men and women should monitor their bone density as they age. Women older than 65 years and men older than 75 years should have the screening test. All women and men in the “at risk” category should have the test earlier.
Factors including smoking, drinking excessive alcohol, sedentary lifestyle, estrogen loss in women, and insufficient intake of Vitamin D and calcium can cause an aging person’s bones to become less dense and strong. Other diseases that can contribute to loss of bone density include diabetes, kidney disease, liver disease and a family history of osteoporosis.
Screening for Bone Density
The most common method of detecting bone density is x-ray of the spine, wrist and hip. A special technique called absorptiometry produces a score to measure bone density. Depending on the score, people are classified as normal, osteopenic, or as having osteoporosis. These classifications are important since they define the risk of fractures (refer to Table 1 with T-scoring). Forty percent of post-menopausal women are classified as osteopenic and should receive treatment. Approximately 10 percent of women and a lesser percentage of men are diagnosed with osteoporosis.
Prevention and Treatment of Low Bone Density
Low bone density, like so many things as we age, can be prevented through exercise, proper diet and adequate intake of Vitamin D and calcium. The daily requirement for women and men older than 65 years is approximately 1,500 milligrams (mg) of calcium and a minimum of 800 international units (IU) of vitamin D every day. These supplements are often found in vitamin pills or as separate pills in divided doses taken with food.
Regular exercise with emphasis on strength and weight-bearing as opposed to pure aerobic is best for bone strength. Avoiding smoke and too much caffeine and alcohol is also beneficial for maintaining bone density. These strategies also can help prevent many other diseases. Some women’s doctors may prescribe hormone therapy to replace estrogen.
As we age, metabolism can change, which has a direct bearing on bone strength. If bones become fragile, they may become predisposed to fractures, sometimes resulting in reduced independence and other lifestyle changes. Prevention and early detection are important. Fortunately, exercise and good diet are helpful in preventing osteoporosis and other diseases. Also, many treatments are available to slow down or stop the loss of bone density.
What your score means
Above -1: Normal
Your bone density is considered normal.
Between -1 and -2.5
|Osteopenic: Your score is a sign of osteopenia, a condition in which bone density is below normal and may lead to osteoporosis. Requires preventive measures and treatment.|
|Osteoporosis: Your bone density indicates you have osteoporosis. Increased risk of fracture. Requires physician directed treatment.|
* Your T-score is your bone density compared with what is normally expected in a healthy young adult of your gender. Your T-score is the number of units — standard deviations (SD) — that your bone density is above or below the standard.
MUSCHealth.com Online Library Link:
Bone Density Test
Risk Factors for Osteoporosis
Although the exact medical cause for osteoporosis is unknown, a number of factors contribute to osteoporosis, including the following:
Bones become less dense and weaker with age.
Caucasian and Asian women are most at risk, although all races may develop the disease.
Body Weight and Bone Structure
People who weigh less and have small body frames are more at risk for developing osteoporosis.
The following lifestyle factors may increase a person's risk of osteoporosis:
- Physical inactivity
- Excessive alcohol use
- Dietary calcium and vitamin D deficiency
- Certain medications
- Family history of bone disease