Calcium toxicity refers to an excess of calcium within the human body, also known as hypercalcemia. It can be the result of medical complications including disease and hormonal imbalances or from consuming too much calcium. A healthy diet generally requires 1,000 mg of calcium per day. One of the most prevalent minerals within the human body, calcium is largely retained by the skeleton and teeth.
Healthy bones and teeth, muscle contraction, and proper nerve function require calcium. It is also vital for cardiovascular health. Low calcium levels cause bones to become brittle, muscles to weaken, and nerve responses to be impaired. High calcium levels can cause kidney problems and prevent the proper absorption of other minerals. Vitamin D helps the body absorb calcium and helps maintain normal calcium levels.
In an individual, calcium toxicity is a very rare occurrence. A balanced diet does not contain enough calcium to produce toxic levels in the bloodstream. In addition to vitamin D, the body produces two hormones, parathyroid hormone and calcitonin, which regulate the amount of calcium outside the skeletal structure. Parathyroid hormones release calcium from the bones when levels are low in the bloodstream, and calcitonin stops the release of calcium when levels are excessive.
About 90% of all cases of hypercalcemia are the result of hyperparathyroidism, a condition in which parathyroid hormones are produced in excess. Specific types of cancer, including breast, lung, and kidney, are known to cause calcium toxicity. Severe dehydration can also be a cause.
Some people who are concerned about getting enough calcium in their diet don't realize that too much calcium can also be dangerous. These people can take calcium supplements, leading to a daily calcium intake of more than 2,500 mg. This is considered the daily limit for calcium intake and should not be exceeded for more than a couple of days.
Various body systems can be affected by calcium toxicity. Stomach aches are common and include diarrhea, nausea, and loss of appetite. Skeletal problems can also occur, causing pain and bone bending. When the kidneys are affected, an individual may experience pain and rapid dehydration. Calcium toxicity can also lead to mental instability, including poor concentration and memory loss.
First-line treatments for calcium toxicity involve increasing fluid and salt intake and taking diuretics, which help the body expel excess calcium by increasing the frequency of urination. The underlying diseases that lead to hypercalcemia require treatment of the disease itself. If nonsurgical treatment therapies are unsuccessful, an operation to remove the malfunctioning parathyroid glands may be necessary.