Metabolic Panel: High Calcium
Calcium is the most abundant mineral in the body. An average healthy male contains 2.5 to 3 pounds of calcium, while an average healthy female contains about 2 pounds. Approximately 99 percent of the body’s calcium supply is found in the bones and teeth, leaving only about 1 percent in the cells and body fluids. Calcium is essential for not only strong teeth and bones, but also for proper nerve impulse transmission, enzyme function, blood clotting, and energy production. The level of calcium in the body is regulated by a complex feedback loop—a pathway that controls a certain physiological function—involving parathyroid hormone (PTH), vitamin D, and calcitonin. The amount of magnesium and phosphorus in the body also affects calcium levels.
It’s important that you consume an adequate amount of calcium, which is found mainly in dairy products (milk, cheese, and yogurt, for example), fish that have bones (such as salmon and sardines), sesame seeds, and leafy green vegetables. As you age, be sure to maintain adequate intake of the mineral, since both high and low levels can increase your chances of developing conditions relating to the bones, heart, kidneys, nerves, and teeth. Hypercalcemia (high calcium) can put you at risk for kidney problems, for example, while long-term hypocalcemia (low calcium) typically leads to osteoporosis—the gradual thinning of bone tissue and loss of bone density.
A blood calcium test (also called an ionized calcium test) indicates the amount of calcium in the blood, not the bones. This amount is reflected in the results of a total calcium test, which measures both free (circulating) and bound forms of calcium in the blood. The reference ranges for blood calcium levels, which are measured in milligrams per deciliter (mg/dL), are provided below. Results that fall within the normal range generally mean that calcium is being properly metabolized, so there is no specific target range.
|Reference Ranges for Calcium|
|Category Greater than 12||Very high (Moderate to severe hypercalcemia)|
|10.2 to 12||High (Mild hypercalcemia)|
|8.6 to 10.2||Normal|
|Less than 8.6||Low (Hypocalcemia)|
A urine calcium test may also be ordered if, for instance, a person is exhibiting classic symptoms of kidney stones. Men should produce less than 300 mg of urine calcium per day, and women, less than 250 mg per day. Amounts greater than 300 mg per day can indicate that too much calcium is being consumed or, alternatively, being pulled from the bones. High urine calcium levels may also mean that too much calcium is being absorbed from the intestines, which occurs in certain diseases like sarcoidosis. Leaking, or the loss of calcium due to compromised kidney function, may also be to blame. In general, 100 to 300 mg per day can be considered normal, depending on the individual. If a calcium test indicates that your level is abnormal, work with your physician to determine the source of the problem and begin treatment.
WHAT CAUSES HIGH CALCIUM?
The medical term used to describe too much calcium in the blood is hypercalcemia, a condition that affects less than 1 percent of the population. In most cases (about 98 percent), hypercalcemia is caused by parathyroid disease, or hyperparathyroidism, which occurs when an excess of parathyroid hormone is continually released by the parathyroid glands. The number one cause of this disease is the growth of benign tumors in the parathyroid glands, which are responsible for controlling the levels of calcium and phosphorus in the blood. Kidney disease can also cause the parathyroid glands to become overactive, as it disturbs blood calcium and phosphorus levels and, therefore, disrupts feedback to the parathyroid glands. Additional causes of hypercalcemia include:
- Adrenal gland failure
- Advanced liver disease
- Certain cancers, including breast cancer, lung cancer, leukemia, and prostate cancer (with bone metastasis)
- Diet very high in calcium (more than 2,000 mg per day)
- Familial hypocalciuric hypercalcemia, a hereditary condition that hinders the body’s ability to regulate calcium properly
- High levels of vitamin A and/or vitamin D
- Kidney disease or kidney failure
- Medications, such as calcium-containing antacids, lithium, and thiazide diuretics
- Prolonged immobilization
- Sarcoidosis (disease leading to inflammation in various organs)
Since hypercalcemia can be detected and, in most cases, effectively treated, long-term complications are unlikely. But there are several health problems that may be connected to hypercalcemia, including heart arrhythmias (irregular heartbeat), high blood pressure, intestinal disorders (such as peptic ulcer disease), kidney stones, kidney failure, thyroid disease, vitamin D toxicity, and occasionally vitamin A toxicity. You may also show low levels of iron, magnesium, vitamin K, and/or zinc, which share absorption sites with calcium in the intestines and, therefore, do not absorb as easily when calcium intake is high. In addition, high calcium levels are associated with changes in the nervous system, resulting in confusion and dementia. And although osteoporosis (bone thinning) is more commonly linked to low calcium levels, it is also possible to develop this condition, as well as other bone diseases, as a result of long-term hypercalcemia. If high blood calcium is caused by the bones’ release of calcium into the blood, bone density loss occurs over time. This is why it is important to detect and reverse hypercalcemia before it has a chance to damage the body.
WHAT ARE THE SYMPTOMS OF HIGH CALCIUM?
Mild hypercalcemia usually does not have symptoms, but moderate or severe cases may cause abdominal pain, constipation, depression, fatigue, headaches, nausea, and vomiting. Loss of appetite may occur as well, while thirst and the urge to urinate increases considerably. Remember, though, that these physical indicators can stem from a number of health conditions, not just hypercalcemia. If you experience a symptom that persists or worsens, a visit to your doctor is in order.
HOW CAN HIGH CALCIUM BE TREATED?
The method used to treat high calcium levels is dependent upon the underlying source of the condition, which must be determined by a full medical examination. Hypercalcemia should be treated medically and only under the supervision of a physician. For hypercalcemia that is caused by hyperparathyroidism, doctors may recommend parathyroid surgery, while treatment for cancer-induced cases varies according to the overall goals of cancer therapy. But the most common approach to treatment is medication and/or lifestyle modification.
Usually, medication is prescribed only for severe cases of hypercalcemia. The choice of drug depends on the cause of the condition, as well as the overall health of the patient. The drugs listed in the table below help stabilize calcium metabolism and absorption, normalize parathyroid gland function, and increase calcium excretion. Always ask your physician about potential risks, side effects, and interactions before taking any drug. If you experience a side effect that persists or intensifies, you should notify your medical provider.
|Drugs for High Calcium|
|Bisphosphonates (alendronate, ibandronate, pamidronate, zolendronic acid) Aredia, Boniva, Fosamax, Zometa (administered intraveneously)||Bisphosphonates can deplete calcium and phosphorus from the body. Potential side effects may include abdominal pain, nausea and/or vomiting, gas or bloating, bone loss, ulcers, and irregular heartbeat.|
|Calcimimetics (cinacalcet) Sensipar||Tell your treating doctor if you have a history of liver disease or seizures, or if you are pregnant or breastfeeding. Seek medical attention if side effects such as upset stomach, dizziness, weakness, and chest pain persist or worsen.|
|Calcitonin (injection or nasal spray) Calcimar, Cibacalcin, Miacalcin||Side effects can include bone pain, nausea and/or vomiting, and runny nose.|
|Gallium nitrate Ganite||This drug is used to treat only cancer-related hypercalcemia and is given intravenously under medical supervision.|
|Loop diuretics (bumetanide, furosemide, torsemide) Bumex, Demadex, Lasix||Loop diuretics may cause depletion of calcium, magnesium, potassium, vitamin B1, vitamin B6, vitamin C, and zinc. Side effects may include bone loss, confusion, dry mouth, fatigue, headache, irregular heartbeat, mood changes, muscle cramps, nervousness, numbness, and poor wound healing.|
|Phosphate salts (dicalcium phosphate, dibasic calcium phosphate)||Side effects may include upset stomach and/or vomiting.|
The supplements listed in the following table may also be effective for improving conditions that can cause high calcium levels. Remember, nutritional supplements can be obtained without a prescription, but you should not take any supplement without consulting a healthcare professional. Health risks are possible when using a substance of any kind.
|Supplements for Conditions Related to High Calcium|
|Green tea or green tea extract||3 to 6 cups (tea) or 250 mg one to two times a day (extract)||Green tea is reported to decrease kidney stone formation, which may be due to high calcium levels, as well as improve bone density in elderly women. If taking an extract, use a form standardized to 90- percent polyphenols (specifically EGCG). The supplement may increase blood thinning, especially if you are taking aspirin or anticoagulant drugs.|
|Magnesium||250 to 500 mg twice a day||Use magnesium aspartate, citrate, taurate, glycinate or any amino acid chelate. Supports bone building and balances calcium intake. The ratio of calcium-tomagnesium intake should be between 1 to 1 and 2 to 1. This supplement is reported to improve blood vessel function and insulin resistance, in addition to decreasing LDL cholesterol, total cholesterol, and triglycerides. Also essential for phase-I liver detoxification. If you experience loose stools after taking magnesium, cut your dose in half and gradually increase over the course of a few months. Consult your health-care provider for dosage advice.|
|Shatavari||250 to 500 mg twice a day||Similar to the asparagus growing in your garden, Shatavari has been used for centuries in Ayurvedic medicine. Studies have found that it is a good source of phytoestrogens, which improve calcium-regulating processes in the body. It is also reported to balance cholesterol, improve immunity, and have antioxidant and gastrointestinal-protective properties. Should not be consumed by people with kidney or heart problems, or by women who are pregnant or breastfeeding, unless under the supervision of a doctor.|
Lifestyle approaches to treating hypercalcemia depend on the underlying cause of the condition. When hyperparathyroidism or cancer is the cause, you should follow the advice of your doctor for adjusting your diet and lifestyle. If you have elevated calcium due to failing kidneys, decreasing calcium intake is necessary. The following recommendations may also help hypercalcemia related to impaired kidney function:
- Consider supplementing with magnesium. Magnesium helps prevent kidney stones, which are sometimes a cause of chronic kidney failure. It also improves insulin action in the body, aids in controlling high blood pressure, and is needed to utilize calcium in the bones more efficiently.
- Control your homocysteine levels. Homocysteine, an amino acid byproduct, can damage the kidneys when high amounts are present in the blood.
- Decrease your consumption of milk and dairy products. Better yet, cut them out of your diet entirely. Substitute cow’s milk with almond or soy milk, and choose products that do not use dairy ingredients.
- Detoxify your kidneys. Eating foods like artichokes, asparagus, celery, melons, and parsley—all of which have detoxifying properties—will cleanse your kidneys effectively.
- Drink more water. Sufficient water intake improves the kidneys’ ability to filter toxins and other substances that can cause kidney stones.
- Incorporate low-calcium foods into your daily diet. This food group includes apples, asparagus, beets, cantaloupe, chicken, cottage cheese, eggplant, grapes, pineapple, pinto beans, strawberries, and tomatoes.
- Limit your use of analgesics (painkillers). Drugs like ibuprofen and naproxen sodium can cause kidney failure with overuse.
- Manage any health conditions that are related to your failing kidneys. Poorly managed diabetes and high blood pressure are two of the biggest causes of kidney failure. If you have high blood pressure, ask your doctor about taking an ACE inhibitor. These drugs have been found to prevent the loss of protein in the kidneys, and thus may help you avoid kidney failure.
- Reduce or eliminate your intake of soft drinks. These beverages contain phosphoric acids (phosphates), which can cause calcium depletion in your bones. In addition, studies have found that drinking colas can raise the risk of kidney stones, and that drinking two or more soft drinks per day more than doubles your risk of chronic kidney disease.
Of course, it’s wise to follow the guidelines above even if your hypercalcemia is not due to kidney problems. Additionally, it’s important to stay out of the sun when you have hypercalcemia, since excess vitamin D can contribute to the condition. When venturing outside, wear sunscreen with an SPF of at least 30, and wear long pants and sleeves to cover exposed skin until your calcium levels return to normal. Exercise is also recommended, since regular physical activity promotes healthy bone density. Weakened bones are a common result of hypercalcemia, as high blood calcium levels mean that it is being lost in the bones. Seek out the advice of a fitness professional or doctor to ensure you choose safe exercises that stimulate bone calcium production.
Read additional excerpts for free