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Calcium (Ca) in Blood Test

Test Overview

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A test for calcium, Opens dialog in the blood checks the calcium level in the body that is not stored in the bones. Calcium is the most common mineral in the body and one of the most important. The body needs it to build and fix bones and teeth, help nerves work, make muscles squeeze together, help blood clot, and help the heart to work. Almost all of the calcium in the body is stored in bone.

Normally the level of calcium in the blood is carefully controlled. When blood calcium levels get low (hypocalcemia, Opens dialog), the bones release calcium to bring it back to a good blood level. When blood calcium levels get high (hypercalcemia, Opens dialog), the extra calcium is stored in the bones or passed out of the body in urine and stool. The amount of calcium in the body depends on the amount of:

Vitamin D and these hormones help control the amount of calcium in the body. They also control the amount of calcium you absorb from food and the amount passed from the body in urine. The blood levels of phosphate are closely linked to calcium levels and they work in opposite ways: As blood calcium levels get high, phosphate levels get low, and the opposite is also true.

Most people who have low or high levels of calcium do not have any symptoms. Calcium levels need to be very high or low to cause symptoms.

Current as of: April 30, 2024

Author: Ignite Healthwise, LLC Staff

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