Human Body Composition in Chemical Elements

 Adapted from "Elemental Composition of the Human Body," Ed Uthman, MD

The table below lists the amount of each chemical element found in the human body from greatest to least abundant. The listing contains each element and the amount in mass units in an average, 175 pound (70-kilogram) body, together with the volume of the element, and the length of a cube side containing the pure element. 

Volumes of solid and liquid elements are based on density at or near room temperature. For gas elements such as oxygen and hydrogen, the density of each is the liquid state at their respective boiling points.

Raw data is from The Elements by John Emsley, 3rd ed., Clarendon Press, Oxford, 1998. 

Table of Human Body Composition

A = Mass of element in a 70-kg (175 lb) body.

B = Volume of purified element

C = Element would comprise a cube this long on one side:

ELEMENT    (A)       (B)          (C)

oxygen        43 kg     37 L        33.5 cm

carbon         16 kg     7.08 L     19.2 cm

hydrogen     7 kg        98.6 L    46.2 cm

nitrogen       1.8 kg     2.05 L    12.7 cm

calcium       1.0 kg      645 mL   8.64 cm

phosphorus  780 g      429 mL    7.54 cm

potassium     140 g     162 mL     5.46 cm

sulfur            140 g      67.6 mL   4.07 cm

sodium         100 g      103 mL    4.69 cm

chlorine         95 g      63 mL       3.98 cm

magnesium    19 g     10.9 mL     2.22 cm

iron                4.2 g     0.53 mL    8.1 mm

fluorine          2.6 g     1.72 mL   1.20 cm

zinc                2.3 g     0.32 mL   6.9 mm

silicon            1.0 g     0.43 mL   7.5 mm

rubidium        0.68 g   0.44 mL   7.6 mm

strontium       0.32 g    0.13 mL   5.0 mm

bromine         0.26 g    64.2 µL    4.0 mm

lead               0.12 g     10.6 µL    2.2 mm

copper           72 mg     8.04 µL    2.0 mm

aluminum     60 mg     22 µL       2.8 mm

cadmium      50 mg     5.78 µL    1.8 mm

cerium          40 mg     4.85 µL    1.7 mm

barium          22 mg     6.12 µL     1.8 mm

iodine           20 mg     4.06 µL     1.6 mm

tin                 20 mg     3.48 µL     1.5 mm

titanium        20 mg     4.41 µL     1.6 mm

boron           18 mg     7.69 µL      2.0 mm

nickel           15 mg     1.69 µL     1.2 mm

selenium       15 mg     3.13 µL     1.5 mm

chromium     14 mg     1.95 µL     1.3 mm

manganese  12 mg     1.61 µL     1.2 mm

arsenic         7 mg      1.21 µL      1.1 mm

lithium         7 mg     13.1 µL       2.4 mm

cesium          6 mg     3.2 µL         1.5 mm

mercury        6 mg     0.44 µL       0.8 mm

germanium    5 mg     0.94 µL      1.0 mm

molybdenum 5 mg     0.49 µL      0.8 mm

cobalt             3 mg     0.34 µL     0.7 mm

antimony       2 mg     0.30 µL     0.7 mm

silver             2 mg     0.19 µL     0.6 mm

niobium         1.5 mg  0.18 µL    0.6 mm

zirconium      1 mg      0.15 µL   0.54 mm

lanthanium    0.8 mg   0.13 µL   0.51 mm

gallium          0.7 mg   0.12 µL   0.49 mm

tellurium       0.7 mg    0.11 µL   0.48 mm

yttrium         0.6 mg     0.13 µL   0.51 mm

bismuth        0.5 mg     51 nL      0.37 mm

thallium       0.5 mg     42 nL      0.35 mm

indium         0.4 mg     55 nL     0.38 mm

gold             0.2 mg     10 nL     0.22 mm

scandium     0.2 mg     67 nL     0.41 mm

tantalum      0.2 mg     12 nL     0.23 mm

vanadium    0.11 mg    18 nL    0.26 mm

thorium       0.1 mg      8.5 nL   0.20 mm

uranium      0.1 mg      5.3 nL   0.17 mm

samarium    50 µg       6.7 nL   0.19 mm

beryllium    36 µg       20 nL    0.27 mm

tungsten      20 µg       1.0 nL   0.10 mm

Notes:

Oxygen is the most abundant element in the earth's crust and in the body. The body's 43 kilograms of oxygen is found mostly as a component of water, which makes up 70% of total body weight.

Oxygen is also an integral component of all proteins, nucleic acids (DNA and RNA), carbohydrates, and fats.

Rubidium is the most abundant element in the body (0.68 g) that has no known biological role (silicon, which is slightly more abundant, may or may not have a metabolic function).

Vanadium is the body's least abundant element (0.11 mg) that has a known biologic role, followed by cobalt (3 mg), the latter being a constituent of vitamin B12.

The last of the body's elements to be discovered was fluorine, by Moissan in 1886.