Osteoporosis is the progressive loss of bone density. It is often called the "silent killer" because the condition can often go undetected until it is severe and fractures begin to occur. Sadly, if undetected, the degree of bone loss can leave a person disabled and in a great deal of pain. Bone density is not a subject that many people think about on a daily basis, and so this "silent thief" can steal much of the calcium and mineral strength from your bones. Most commonly a loss in bone density is associated with changes women experience during menopause as the decreased hormonal levels affect the calcium balance in the blood and bone mass is lost as a result. Also,increased amounts of phosphorus from sources such as carbonated beverages, fast foods, and preservatives can contribute to a calcium deficiency by lowering the available blood calcium.
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As the most plentiful mineral in the body, calcium plays a key role in the development and maintenance of bones and teeth. Calcium enables the contraction of muscles, including the function of the body's most important muscle, the heart. It is also essential for normal blood clotting, proper nerve impulse transmission, and the appropriate support of connective tissue. Almost every segment of the population--women, children, teenagers, men, unborn babies, and the elderly--benefit from calcium in their daily diet. The mineral is an important dietary supplement for those who are undergoing significant periods of bone growth, such as in childhood, and during pregnancy, and breastfeeding.
Hormone replacement therapy is used to treat both menopausal symptoms and the osteoporotic changes and associated bone loss. This can happen too if other endocrine disorders are present in either male or female patients, since the endocrine system controls the levels of the hormone calcitonin which, in turn, affects the level of calcium in the body.
Kidney injuries or malfunction, vitamin deficiencies and steroid use are also known causes for the decrease in bone density known as osteoporosis.
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Do I have osteoporosis?
Only your physician can diagnose your condition to determine whether you have experienced bone loss or changes in bone density. Often osteoporosis patients don't know that they're at risk, or they're suffering silently. Screening tests, similar to low radiation x-rays, are commonly used to scan the heel, the wrists, the spine, or even the whole body to find weakened points or potential hairline fractures. If you suspect that you're at risk for osteoporosis, talk to your doctor about your risk factors and consider a bone densitometry procedure to evaluate your bone density. Increasing your calcium intake and ensuring a sufficient intake of critical vitamins and minerals each day can help to decrease your risk.
Bone Loss
As a patient ages, some bone loss is expected due to the breakdown of the bone remodeling cycle. Primarily two types of cells perform the cycle. During the bone remodeling cycle, osteoclasts are used to break down areas of bone density loss and osteoblasts rebuild and remodel the areas left vacant by osteoclasts.
The function of these two types of cells is supported by a sufficient supply of the minerals and vitamins needed for this exchange. Bone remodeling occurs rapidly in children and is responsible for the growth in the skeleton we see during this period; however, this process slows once the adult has reached full skeletal maturity in the mid to late twenties.
Bone remodeling in the normal (non-osteoporotic) adult occurs at a consistent rate. The bone remodeling responsible for maintaining bone density slows somewhat around age 40, so some slight bone loss is expected and considered normal after this age. In contrast, osteoporotic patients experience a dramatic bone loss often beginning in their 20s and 30s when vitamin, mineral and hormonal deficiencies are present. Adults at risk for osteoporosis should look into having a test (bone densitometry) to determine the amount of bone loss.
Since a loss of strength and balance is also associated with osteoporosis, it is important to note the types of fractures that are often found.
Common sites for breaks from falls include the wrist, hip, ankle and heel. Aside from having the painful disuse of the affected area, when human bones are broken a life-threatening risk develops. The risk of fracture is particularly high in patients with advanced osteoporosis with the long bones, such as leg bones, that break simply under the strain of standing.
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A bone scan is similar to an x-ray: it takes a "picture" of your bones to determine whether you have bone fractures, inflammation or tumors. The bone scan is sensitive enough to detect areas in which structural changes are occurring, possibly detecting bone infections or other concerns. A bone scan, though, is able to detect these changes long before a conventional x-ray would pick them up.
Before performing a bone scan, a radiologist will inject special bone imaging substance into your bloodstream. A few hours later, the patient returns to the facility to have the actual bone scan performed. You will be asked to drink large amounts of water at this time.
The bone scan is performed using a large machine similar to an x-ray machine. The patient lies on a sliding table that moves beneath the imaging device that actually performs the bone scan on selected parts of the body or even the entire skeleton if desired.
The scan takes about an hour, and you may have to wear a gown, but generally the test is non-invasive and painless. You may experience a bit of discomfort from a full bladder or your arm may be tender at the site of the injection.
The radiologist evaluates the scan results and sends the information to your doctor.
The Bone Density Test
A bone density test, also called a bone mineral density test (BMD) or bone densitometry, measures the strength of bone and the mineral concentration in your skeleton. A bone density test can help physicians understand what treatments, if any, are needed to arrest further bone loss and perhaps reverse the effects of osteoporosis.
This test can also reveal whether there has been an insufficient amount of calcium in your body, and assist you in making better nutritional choices. Vitamin and mineral supplements may be appropriate in the osteoporosis patient.
The bone density test is fast and easy. Several types of bone density tests are available:
Preventing Osteoporosis
Osteoporosis is one of the most preventable of bone diseases. Preparing yourself to avoid it is not a difficult task. Exercise is important as it maintains the strength of bones through uses such as aerobics, stair climbing, hiking, or walking. For the patient with osteoporosis, exercises that can cause a higher impact should be avoided since this can lead to fractures. In younger patients, weight bearing exercise is an important preventive strategy as it helps to increase total bone mass.
Prevention focuses on nutrition for bones, including a sufficient calcium intake of 1000 to 1500 mg/day. The average American consumes less than 800 mg of calcium per day. An appropriate diet, without excessive proteins, and low in alcohol can assist in the maintenance of healthy bones. Increased alcohol and protein in the diet can block the absorption of calcium in the intestine. The presence of vitamin D in the intestines is critical to the absorption of calcium. Other vitamins are also important in the absorption of calcium. Vitamins A, B6, C, and K are all vital to the absorption of calcium and when included in a daily multivitamin can slow the onset of osteoporosis.
There are at least a dozen common calcium preparations and hundreds of different formulations available. Calcium carbonate is the most common preparation; some others include tricalcium phosphate, dicalcium phosphate, bone meal, calcium citrate-malate, oyster shell, calcium lactate, and calcium gluconate. These calcium preparations differ in a variety of ways. Calcium carbonate has the highest concentration of calcium by weight (40%), whereas calcium citrate has 21% calcium, calcium lactate contain 13%, and calcium gluconate contains 9 %, and calcium phosphate has 8% calcium by weight. Although calcium carbonate has the highest concentration of calcium by weight, this form of calcium is relatively insoluble, especially at a neutral pH. In contrast, calcium citrate, although containing about half as much calcium by weight, is a more soluble form of calcium. Because calcium citrate does not require gastric acid for absorption, it is a better choice for patients with achlorhydria (limited gastric acid production).
It is recommended that other medications be taken two hours after any calcium supplement. The simultaneous intake of calcium may interfere with the absorption of other drugs. Do not take more than 500 mg of calcium at one time for the best absorption of the mineral.
How to choose a supplement
Note that, as a rule, a daily multi-vitamin does not contain enough calcium to suffice as a supplement.
Age |
Daily calcium requirement |
4 to 8 |
800 mg |
9 to 18 |
1300 mg |
19 to 50 |
1000 mg |
50+ |
1500 mg |
pregnant or lactating women 18+ |
1000 mg |
Vitamin D: A key factor in good calcium absorption
Vitamin D3 increases calcium absorption by as much as 30 to 80 percent.Adults aged 19 to 50, including pregnant or lactating women, should receive 400 international units (IUs) of vitamin D3 per day. Adults over 50 should receive 800 IUs.
Milk fortified with vitamin D3 contains 100 IUs per 250 ml glass. Foods such as margarine, eggs, chicken livers, salmon, sardines, herring, mackerel, swordfish and fish oils (halibut and cod liver oils) all contain small amounts.
Since it may be difficult to get enough vitamin D3 from food alone, you may wish to consider supplements. Most multi-vitamins provide 400 IUs of vitamin D3. Some calcium supplements also contain vitamin D3.
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