IRON

IRON
    Those elements which are required in traces or minute quantities are known as trace elements. Iron is a trace element, as its presence in small amount is very significant. Most of the iron in the body is present as hemoglobin. Most of the body’s iron is found in complex forms bound to proteins either as porphyrin or heme compounds or as ferritin. Free inorganic iron occurs in small amount. About 70% of iron is in circulating hemoglobin, 4% as myoglobin. 25% is stored in liver, spleen, kidney and 1% in plasma and various oxidative enzymes.

    Functions
    • For the formation of haemoglobin: Haemoglobin is the main component of red blood cells. It is composed of iron and protein (Heme+globin). Heme is a compound of iron and its synthesis depends upon the quantity of iron in the blood. Haemoglobin acts as a carrier of oxygen from the lungs to the tissues and indirectly helps in the return of carbon dioxide to the lungs.
    • Essential constituent of muscles: Myoglobin is an iron-protein complex found in muscles which stores some oxygen for immediate use by the cells. Transferrin of siderophilin is the circulating form of iron. Ferritin or haemosiderin is the storage form of iron.
    • Enzymes like catalyses, xanthine oxidase contain iron as an integral part of the molecule
    • Small amount of iron available in plasma, which is 1-2% of total iron in the blood. Iron in plasma is utilized in transportation, for example ferritin, transferritin etc.

    Deficiency
    • Deficiency of iron may be caused in a number of ways. The diet may not provide enough iron or it may be in un absorbable form.

    Anemia
    • In healthy individual blood contains approximately 14g of haemoglobin per 100 ml.
    • Sometimes the level goes down and a low level of haemoglobin in blood is called anaemia.
    • Anemia occurs when diet is deficient in one or other of the nutrients required for the synthesis of haemoglobin.
    • Due to excessive intake of antibiotics bone marrow is unable to synthesize red blood cells.
    • Iron is essential for the synthesis of the haemoglobin. It is also present in myoglobin and other proteins such as the cytochromes.Much of the iron in food is unabsorbable because it is irreversibly bound to phytates and phosphates.Also, iron is readily oxidized to ferric form in which it cannot be absorbed.
    • Anaemia is a condition in which total circulating haemoglobin reduces.This can be due to deficiency of one or more essential nutrients (iron, calcium, copper, vitamin C, folic acid, vitamin B12, protein etc). Iron deficiency anaemia follows a specific sequence.The iron reserves getting depleted and transferrin (transport form of iron) level of blood goes on increasing and plasma iron is reduced.The blood cells are pale, less in number and small in size.This is usually by blood loss but occasionally iron may be excreted in urine and cause haemosidernuria.

    Types of Anaemia
    Hypochromic anaemia: Such a state is usually associated with chronic inflammatory disease in which there is an inhibition of mobilization of iron from body stores. The iron storage sites in the marrow show abundant iron but is not available for haemoglobinisation of developing red cells.

    Sideroblastic Anaemia: These are rare conditions in which red cell production is impaired by disordered iron metabolism. Heredity can be one of the causes.

    Megaloblastic anaemia: Red cells appear abnormally large. Normally in red cell production, cell division occurs rapidly. Between division the cells do not have time to re-grow to their full size and progressive reductions in cell size occurs. When DNA (deoxyribose nucleic acid) synthesis is reduced, the time between divisions is increased, more cell growth occurs and cells size decreases.

    Pernicious anaemia: Absence of free hydrochloric acid in the stomach results in inability to absorb iron. This is due to degenerative changes in nervous system result in tingling sensation of finger and toes, loss of vibratory sense and impaired co-ordination. There is lack of appetite, weight loss, diarrhoea, constipation and shortness of breath.
    Anemia Symptoms of Anemia Spoon shaped nail
    IRON IRON IRON

    Hemosiderosis
    It is a disorder of iron metabolism.
    In this conditions large amounts of iron are deposited in the liver and in the recticulo endothelial system.
    Transferrin, the iron with carrier protein becomes saturated with iron.
    When transferrin is unable to bind all the absorbed iron this metabolic disorder takes place.
    If iron vessels are used for cooking, much more iron is ingested into the body, which may result in hemosiderosis.
    The Bantu population of Africa is an example of this condition.
    In hemolytic anemia a large number of red blood cells are destroyed and this can lead to hemosiderosis.
    Prolonged prophylaxis with massive doses of iron can often produce hemosiderosis.

    Sources of Iron
    Best Sources : Liver, kidney, heart, lean meat, egg yolk and shellfish.
    Good Sources : Dried beans, legumes, dried fruits, nuts, green leafy vegetables, whole cereals, enriched grains and molasses.
    Poor Source : Milk

    Requirement of iron
    Recommended intake of iron is calculated, based on its loss and absorption.
    Adult man -17mg/day
    Adult woman -21mg/day
    Pregnancy - 35 mg/day
    Lactation -25 mg/day
    Infants -0.5mg/kg body weight
    Children g/day
    1-3 years - 09
    4-6 years - 13
    7-9 years - 16
    Boys
    10-12 years - 21
    13-15 years - 32
    16-18 years - 28
    Girls
    10-12 years - 27
    13-15 years - 27
    16-18 years - 26
Last modified: Monday, 4 June 2012, 6:17 AM