Our body is made up of more than 20 different chemical elements, the greatest part being oxygen. Oxygen combined with hydrogen forms water, and our body contains 65% of water. A person weighing 100 kilograms contains approximately 65 kilograms of water. Did you know that our body has carbon equal to nearly 13 kilograms of coke? Carbon combined with hydrogen and oxygen make fats and sugars, which produce energy in the body. Our body also contains proteins, which are made of carbon, hydrogen, oxygen and nitrogen. Proteins are used for the growth and repair of the body parts. The body also contains calcium and phosphorus — it contains about 1.25 kilograms of calcium and enough phosphorus. Both these elements form essential parts of the bones and teeth. The body also contains sulphur, iron and other metals. But these elements are present in traces.