Phosphorus is an essential mineral that is usually found in nature combined with oxygen as phosphate. Most of the phosphate in the human body is in bone, but phosphate-containing molecules (phospholipids) are also important components of cell membranes and lipoprotein particles, such as HDL and LDL (“good” and “bad” cholesterols, respectively). Small amounts of phosphate play important roles in numerous biochemical reactions throughout the body.