The normal level of calcium intake per day for adults is 1,000mg for men and 1,200mg for women aged 50 years and above. Hypercalcemia is a condition caused due to abnormally high levels of calcium in the blood. This condition usually develops due to hormonal imbalance, wherein there is an overproduction of parathyroid hormones. These hormones are overproduced, there is faster release of calcium in to the blood from the bones.
In normal situation, this speedy release would be checked by a hormone called calcitonin. With high calcium levels in the blood, calcitonin loses its ability to match up with the parathyroid hormone. There are many conditions which can cause this imbalance. If left untreated, it can cause osteoporosis, kidney failure or stones or abnormality in the heart rhythm.
The most common cause of high calcium in blood is overactive parathyroid gland. This usually occurs due to enlargement of the gland. When more than one gland is involved, the condition is called hyperplasia. The overproduction can also be caused by any benign growth on the gland.
The other cause for high calcium level in the blood can be caused by excessive consumption of calcium supplements. This is less unlikely to occur when natural products like milk or other dairy products which are rich in calcium are consumed in very high quantities. The chances of over dose of calcium by consuming multi-vitamin or mineral supplements are less since these do not contain very high amounts of the mineral.
Over-consumption of Vitamin D supplements can also cause hypercalcemia. This is because Vitamin D is the mineral which maintains balance between the calcium level in the bones and blood. In order to prevent overdose of the vitamin, the recommended level of Vitamin D intake from different sources is limited to 50 mcg per day.
The chance of cancer of parathyroid gland causing overproduction of hormones resulting in hypercalcemia is rare. Cancers associated with this condition are breast cancer, lung cancer or multiple myeloma. All these cancers have the ability to infiltrate and spread to the bones. Certain substances get released by malignant tumors which encourage transfer of calcium from the bones to the blood. In hypercalcemia, the kidneys also fail to release excess calcium in the blood.
Conditions, like Paget’s disease, which cause breakdown of the bone tissue also result in increase in calcium level in the blood. HIV, AIDS, lymphoma, Addison’s disease and sarcoidosis can also cause hypercalcemia.