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Overview of Phosphate

by James L. Lewis, III, MD

In the body, almost all phosphorus is combined with oxygen, forming phosphate. Bone contains about 85% of the body’s phosphate. The rest is located primarily inside cells, where it is involved in energy production.

Phosphate is necessary for the formation of bone and teeth. Phosphate is also used as a building block for several important substances, including those used by the cell for energy, cell membranes, and DNA (deoxyribonucleic acid). The body obtains phosphate from foods and excretes it in urine and stool.

The level of phosphate in the blood may be too high (see Hyperphosphatemia (High Level of Phosphate in the Blood)) or too low (see Hypophosphatemia (Low Level of Phosphate in the Blood)).