Elements. [ Home page ] [ Faculty and Staff ] [ Teaching ] [ Research ] PERCENT COMPOSITION OF THE HUMAN BODY BY MASS MAJOR ELEMENTS

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1 [ Home page ] [ Faculty and Staff ] [ Teaching ] [ Research ] Elements PERCENT COMPOSITION OF THE HUMAN BODY BY MASS MAJOR ELEMENTS OXYGEN 62.5 CARBON 19.5 HYDROGEN 10.0 NITROGEN 3.0 MAJOR MINERALS TRACE MINERALS (less than 0.1 %) CALCIUM 1.7 IRON PHOSPHOROUS 0.9 IODINE POTASSIUM 0.3 ZINC SULFUR 0.2 CHROMIUM SODIUM 0.2 SELENIUM CHLORINE 0.2 FLUORINE MAGNESIUM 0.04 COBALT MOLYBDENUM COPPER MANGANESE VANADIUM TIN SILICON NICKEL Elemental composition of human body You are a mixture of thousands of compounds that are constantly being used and replaced by chemical reactions. These compounds either are obtained directly from food sources or are formed by chemical reactions from compounds in foods. The elemental composition of the human body is given in the table. Your body contains about 60% water (40% intracellular fluid; 20% extracellular fluid), which consist of hydrogen and oxygen. Another substantial fraction of body weight consists of organic compounds (compounds containing carbon) such as fats, carbohydrates, and proteins. These compounds all contain carbon, hydrogen, and oxygen; proteins contain nitrogen as well. Nutritionists characterize another fraction of your body as major minerals. The major minerals calcium and phosphorous are in the bones as calcium phosphate. Calcium also exists in body fluids as calcium ion. Sodium, potassium, and chlorine are important components of body fluids both surrounding cells and within them. The trace minerals are present in quantity barely large enough to fill teaspoon. However, each of them plays a vital role in maintaining life, having a function for which there is no substitute. In many cases not only a deficiency but also an excess would be fatal.

2 Iron is contained in every cell, but most of the iron in the body is found in hemoglobin and myoglobin, two of the oxygen needed for life processes. Zinc occurs in over 70 enzymes that regulate biochemical reactions. Copper and manganese, about 100 and 20 mg respectively are also components of certain enzymes. Iodine is needed in three thyroid hormones that regulate metabolic rate. MAJOR MINERALS CALCIUM Extracellular cation. Almost all of calcium is in the bones and teeth in form of hydroxyapatite ~ Ca 10 (PO 4 ) 6 (OH) 2. Plasma: 2,25 2,75 mmol/l There are three forms of Ca in plasma: - ionised (cca 50%) - protein-bond (35 40%) - as complex with anions of acids (5 10%) (citrate) - bone/tooth formation - blood clotting - heart rhythm - nerve transmission - muscle growth and contraction PHOSPHORUS Most of phosphorus (80%) is combined with Ca 2+ a Mg 2+ in the bones and teeth. Phosphorus is in molecules of phospholipids (cell membranes), phosphoproteins, nucleic acids and sugars in form of esters of phosphoric acid. Phosphates are components of blood buffer systems. - bone/tooth formation - cell growth - energy production (ATP...) - hearth muscle contraction - calcium metabolism - nerve and muscle activity POTASSIUM K + is principle cation of intracellular fluid (ICF) ICF concentration: 115 mmol/l; in serum: 3,8 5,1 mmol/l - heartbeat - muscle contraction - proteosynthesis - osmotic equilibrium

3 - utilization of saccharides SULFUR Sulfur is present in all cells of the body primarily in the cell protein (presence of the two sulfur-containing amino acids cystine and methionine). Sulfur-containing amino acids stabilize tertiary structure of proteins. Higher concentrations of S is in hair and nails (keratin). S is in the molecule of acetylcoenzyme A (CH 3 -CO~S-CoA). - collagen synthesis - body tissue formation - biological oxidation of sugars, fats and proteins SODIUM Na + is principle cation of extracellular fluid (ECF) In serum: mmol/l, ICF: 37 mmol/l - normal cellular fluid level - proper muscle contraction CHLORINE Chlorides are the principal extracellular anions. In serum mmol/l, ICF: 53 mmol/l - maintenance of osmotic balance of extracellular fluid (with Na + ) - formation of hydrochloric acid in gastric juice MAGNESIUM Cation of intracellular fluid (99% of Mg is intracellular. One half is binding in proteins and at a crystals of hydroxyapatite in bones. One half is in muscles, liver and CNS). In plasma: 55 60% is ionised, 30% is binding to protein the rest is complex with anions of acids). Magnesium participates in all biochemical a physiological processes because of their ability to activate (together with Zn) approximately 230 enzymes. - acid/alkaline balance - blood sugar metabolism (energy) - calcium metabolism TRACE MINERALS IRON Fe is in molecule of hemoglobin and myoglobin. Hem is component of cytochroms.

4 In organism, Fe is stored in ferritin. Fe is transported with transferin in blood. - biological oxidation (hemoglobin and myoglobin transport of O 2, cytochroms transport of electrons) - hemoglobin production IODINE I is necessary for function of thyroid gland. Iodine is in thyroid hormones. (triiodthyronine T 3, thyroxin T 4 ). - metabolism of fats - energy production - physical and mental development ZINC Zinc is namely intracellular element. (60% is in muscles, 30% in bones). Zinc is component of some enzymes (carbonatanhydrase, lactatdehydrogenase, alcoholdehydrogenase and superoxiddismutase). Zinc is an activator of about 230 enzymes. - carbohydrate digestion - prostate gland function - reproductive organ growth and development - phosphorous and protein metabolism CHROMIUM - glucose metabolism (energy) - utilization of blood sugars SELENIUM It is component of some enzymes e.g. glutathionperoxidase - antioxidant - synthesis of prostaglandins FLUORINE It is in bones and teeth. COBALT It is component of vitamin B12 (cyanocobalamine). - production of erythrocytes - utilization of glucose and transport of AA into cells

5 MOLYBDENUM It is component of enzyme xanthinoxidase and activator of many enzymes. - synthesis of glycoproteins - releasing of Fe from ferritine - sex hormone production - tissue respiration COPPER It is component of some oxidoreductases (e.g. cytochromoxidase c, lysyloxidase, superoxiddismutase) and plasmatic protein - ceruloplasmine (oxidase). - synthesis of collagen - bone formation - healing processes of body - hemoglobin and red blood cell formation MANGANESE It is component of enzyme xanthinoxidase and activator of many enzymes. - synthesis of glycoproteins - releasing of Fe from ferritine - sex hormone production - tissue respiration VANADIUM Appropriate amounts decreases cholesterol level in blood. TIN It is supposed, that it is necessary for optimal growth and blood formation. SILICON - growth and development of a skeleton - elasticity of muscles, skin, hairs, nails and vessels NICKEL Activator of some important enzymes e.g. alkaline phosphatase (together with Co and Fe) and enzymes needed for biosynthesis of amino acids.