MAGNESIUM
It is an intracellular ion of all living cells and tissues. The total body content of magnesium is 12 grams. Most of this (70%) is present in bones, in combination with calcium and phosphorus.
Functions :
It is a co -factor for a number of enzymes
It exerts neuro muscular irritability like calcium
It is a constituent of bones, dental enamel and dentin
Deficiency :
Loss of magnesium may occur in prolonged vomiting, diarrhoea or in diuretic therapy. Deficiency symptoms are muscle tremor, twitching and convulsions.
SULPHUR
Sulphur is an essential element. It is present in all the cells of the body.
Functions :
It is a constitutent of sulphur containing amino acids
It is involved in the formation of proteins like keratins
It is involved in the formation of SH group containing enzymes
Sulphur is a constitutent of vitamins like biotin and lipoic acid
Deficiency : Deficiency of sulphur does not occur. Adequate protein in diet satisfies sulphur requirement.
IRON
Iron is the essential constitutent of hemoglobin. It is also a component of respiratory enzymes like cytochrome oxidase and catalase.
Functions :
It transports oxygen to the tissues
It takes part in cellular oxidation -reduction reactions
It is a co -factor for enzymes like succinate dehydrogenase and aconitase
Sources : Meat, liver, kidney, egg yolk, fish and green leafy vegetables.
Absorption : Maximum absorption of occurs in the first part of duodenum. A protein called apoferritin in necessary for iron absorption. Iron is not absorbed in the absence of apoferritin. Iron is absorbed only to the extent required by the body. Even in anaemia, only that amount which is required to correct the deficiency is absorbed. Thus, there exists a regulatory mechanism for iron absorption. This regulatory mechanism is called ‘mucosa block’.
Deficiency :
Deficiency of iron produces microcytic hypochromic anaemia. It is also called as iron deficiency anaemia.
Iron excess : Excess iron is deposited in all body tissues and organs. This condition is called as hemosiderosis. When there is bronzed pigmentation of the skin due to deposition of iron, the condition is called hemochromatosis or bronze -diabetes.
IODINE
Iodine has special importance, since it is required for the synthesis of thyroid hormone. A normal adult has 20 to 50 milligrams of iodine in the body. 20% of this is present in the thyroid gland. A normal adult requires 100 to 200 micrograms of iodine per day. Rich sources of iodine are sea foods and vegetables grown near sea coast.
Goiter : It is enlargement of the thyroid gland caused by the deficiency of iodine. It occurs in people living in some regions where the iodine content of water and soil is very low. These regions are called endemic areas for goiter. Goiter can be prevented by using iodized salt or by a adding iodine to drinking water.
FLUORINE
Fluorine is present in bones and teeth. Trace amounts of fluorine is required for the development of bones and teeth. Also have it prevents the development of dental caries.
Dental fluorosis : It is a toxic effect of fluorine on the teeth. It is due to excess of fluorine in water. Fluorosis affects the enamel of teeth. There is mottling or pitting of enamel. The enamel develops white patches, brown stains and pits.
COPPER
The adult human body contains 100 to 150 milligrams of copper. It is widely distributed in all tissues. Liver contains more copper. Foetal liver contains 5 to 10 times more copper than adult liver. Copper in liver is called as hepatocuprein.
Functions :
It is a constitutent of enzymes like cytochromes, catalase, uricase etc.
Along with iron, it is necessary for hemoglobin synthesis and maturation of RBCs
It is required for bone formation
It maintains the myelin sheath of nerve fibres
Deficiency : Deficiency of copper may produce loss of weight, disorders of bone, anaemia and demyelination.
Wilson's disease : It is also called as hepatolenticular degeneration. It is a disease of abnormal copper metabolism. It is a hereditary disease. In this disease, there is increased absorption of copper in the intestine. The excess copper is deposited -
In the liver (which produces cirrhosis)
In the lenticular nucleus of brain (leading to its degeneration)
ZINC
A normal adult has 1.5 to 2.5 grams of zinc in the body. It has a wide distribution in the body. In plasma, it is bound with albumin.
Functions :
It is a constitutent of enzymes like carbonic anhydrase and alcohol dehydrogenase
It is required for insulin secretion
It stimulates the release of vitamin A from liver
It is necessary for wound healing
Deficiency : Deficiency of zinc is rare.
Good topics for medical students
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