What Are the Elements in the Human Body

Most of the human body is made up of water, H₂O, with cells consisting of 65-90% water by weight. Therefore, it isn't surprising that most of a human body's mass is oxygen. Carbon, the basic unit for organic molecules, comes in second. 99% of the mass of the human body is made up of just six elements: oxygen, carbon, hydrogen, nitrogen, calcium, and phosphorus. You may also wish to view the element composition of an average human bodyby mass.

1.        Oxygen (65%)

2.      Carbon (18%)

3.      Hydrogen (10%)

4.     Nitrogen (3%)

5.      Calcium (1.5%)

6.     Phosphorus (1.0%)

7.      Potassium (0.35%)

8.      Sulfur (0.25%)

9.     Sodium (0.15%)

10.  Magnesium (0.05%)

11.     Copper, Zinc, Selenium, Molybdenum, Fluorine, Chlorine, Iodine, Manganese, Cobalt, Iron (0.70%)

12.   Lithium, Strontium, Aluminum, Silicon, Lead, Vanadium, Arsenic, Bromine (trace amounts)

Reference: H. A. Harper, V. W. Rodwell, P. A. Mayes,Review of Physiological Chemistry, 16th ed., Lange Medical Publications, Los Altos, California 1977.

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