2.4 Phosphorus (P), magnesium (Mg) and sulphur (S)
2.4.1 Phosphorus (P)
Like calcium, phosphorus is important in the structure of bones and teeth. It is vital in the body as part of the molecules ATP and DNA, and is also a component of phospholipids, lipoproteins and many other proteins too. Phosphorus can occur, combined with oxygen, in phosphate ions and in this form it plays an important role in switching on and off metabolic pathways in cells. Phosphorus is widely available in the diet, from both plant and animal sources, such as meat, fish, eggs and dairy products, cereals and nuts. It is also added to many prepared foods such as bread and cakes, processed meats and soft drinks. Since the body absorbs phosphorus more efficiently than calcium, intake is usually sufficient for the body's needs, but deficiency could lead to rickets and osteomalacia, as with calcium deficiency.