Phosphorus is a mineral that combines with other compounds to form key building blocks as such phospholipids, nucleic acids (DNA and RNA) and adenosine triphosphate, or ATP, the 'energy currency' of metabolism, which powers virtually every activity in which cells are engaged. Phosphorus also helps maintain the body's acid-base balance. Normally only about 1% of total body phosphates are present in the blood. The body maintains the levels of phosphorus compounds in the blood by regulating how much it absorbs from the intestines and how much it excretes via the kidneys.