Your body typically adapts well to changing levels of dietary calcium. In relatively rare instances, however, your serum calcium levels may become too high or too low. Keep in mind that most adults need a calcium intake in the range of 1,000 to 1,500 mg per day.
When calcium intake is high, perhaps only more than 2,000 mg a day, this may gradually cause calcification of arteries and increase the risk of heart attack and stroke. Therefore “more is better” isn’t always true. It’s probably wise not to exceed 1,000 to 1,500 mg per day unless it’s known that you don’t absorb calcium well.
Symptoms of high blood calcium
When calcium intake is very high — for example more than 4,000 mg in a day — even though the hormones that increase calcium absorption turn off, large amounts of calcium can pass into the body from the intestine and a state of hypercalcemia (too much calcium in the blood) occurs. This can cause kidney stones and, in extreme cases, kidney failure. This condition used to be more common when people took large amounts of antacids for stomach ulcers.
More acute symptoms may accompany the condition of hypercalcemia. If the elevation of calcium is mild, such as 11 or 12 mg/dl, no symptoms may arise. If the calcium level is greater than 12, symptoms may be severe. Among them are these symptoms:
Abdominal pain
Confusion
Excessive thirst and urination
Fatigue and lethargy
Loss of appetite
Muscle weakness
Nausea and vomiting
Treatment of symptomatic hypercalcemia is done under a doctor’s supervision. The patient is given fluids to improve hydration, and they are given a variety of drugs that lower serum calcium levels rapidly. The doctor measures the blood calcium every few hours to determine the success of therapy.
Symptoms of low blood calcium
The symptoms of hypocalcemia (low blood calcium) are quite different. They may occur when total calcium is below 9 mg/dl. The most important are these symptoms:
Anxiety and depression
Dementia and mental retardation
Low blood pressure
Muscle stiffness and spasms
Papilledema (swelling of the optic disc caused by increased pressure in the brain)
Seizures
Treatment of hypocalcemia is also done under a doctor’s supervision. If the condition is mild, oral calcium and vitamin D is taken. If it’s severe, intravenous calcium is administered. Blood calcium levels are measured every few hours to follow the progress of the treatment if intravenous calcium is given.