The percentage of body weight are: Oxygen (65%), hydrogen (10%), carbon (18%), nitrogen (3%), calcium (1.5%), phosphorus (1%), potassium (0,25%), sulfur (0.25%), sodium (0.15%), chlorine (0.15%), magnessium (0.05%), iron (0.006%), fluorine (0.0037%), zinc (0.0032%), copper (0.0001%), iodine (0.000016%), selenium (0.000019%), chromium (0.0000024%), manganese (0.0000017%), molybdenum (0.000013%), and cobalt (0.0000021%).
3% of the human body by mass is nitrogen found in all organisms in molecules such as amino acids which make up protein, nucleic acid (DNA and RNA) and ATP. It is required for protein synthesis and production of several nitrogeneous compounds such as hormones, neurotransmitters, and components of antioxidant defense.
Oxygen together with hydrogen form water which is the dominant solvent found in the body. It is used to balance temperature and osmotic pressure.
Carbon makes up 18% of the body by mass and its role is chieflt structural. it forms the backbone of many organic molecules.
Calcium is the most bountiful mineral in the body stored in bones and teeth that gives them structure and hardness. The body requires calcium for muscle to move and for nerves to bring messages between the brain and every part of the body.