Iron as Mineral – Rich Food Sources, Functions, Deficiency & Daily Requirements for Children, Men & Women

Health Care Guide on Iron (Fe) functions in Human Body, Absorption, Excretion, Regulation facts & disease (Anemia) in word/ .doc / ppt / .pdf format

IRON:

Iron is present in all organisms and in all cells. It is a transient metal capable of being present in Fe2+ (ferrous) and Fe3+ (ferric) forms. Iron is essential for the formation of haemoglobin in RBCs, transport of oxygen and oxido-reduction reactions of the electron transport chain.

Sources:

Food iron can be classified as haem iron and nonhaem iron (iron-porphyrin complexes are referred to haem compounds while nonhaem iron refers to substances which have iron in the prosthetic group but no porphyrin).

• Haeme iron in the body is constituted by Hb (85%), Mb (5%) and heame enzymes (10%) such as cytochromes, cytochrome oxidase and peroxidase. 40% of total food iron is heame iron. It is obtained from organ meats, fish etc.
• Nonhaeme iron is present in Fe-S proteins such as ferredoxin, adrenodoxin, flavoproteins, succinate dehydrogenase transferrin, ferritin, haemosiderin. The food sources of nonhaeme protein are vegetables, fruits, legumes and nuts 60% of total food iron is nonhaeme iron.  

Daily requirement:

-          Adult man and postmenopausal women : 10 mg.

-          Premenopausal women : 15-20 mg.

-          Pregnant women: 30-60 mg.Serum level 11-32umol/L.

-          1 g of haemoglobin contains –3.4 mg iron.

-          - 30 mg iron loss occurs in menstruation.

Iron Deficiency - Anemia in PPT PDF

Presentation Notes on Iron Deficiency, Kinetics of Iron Absorption & How to Diagnose Iron Deficiency in Human Body in word/ .doc Format

Iron Regulation

            If the iron store of the body (ferritin)is nil or low, in presence of severe anemia/pregnancy, the fraction of food iron absorbed rises from 5% to 20% or even 30%. Conversely, in iron overload states, the iron absorption from intestine becomes nearly nil (despite normal iron intake). This is the major mechanism to safeguard that the absorption of iron can be varied according to the need of the body and the mechanism is called "mucosal block" mechanism. Another mechanism is from transferrin, delivery of iron is increased to the cells when the need of the body is great (iron deficiency states) and vice versa.

Iron absorption occurs from duodenum and upper part of jejunum.

Iron Requirement for Women in Pregnancy

Health Care Guide on Iron required per day in Human Body in normal condition & during pregnancy

Daily requirement.

• In adult males, it is about 1 mg/day.
• In the non-pregnant non-lactating women of reproducing age, it is 1.5 to 2 mg/day.
• In pregnancy it is 4mg/day.

Iron Absorption in Human Body

Medical / Biology Notes on Iron Absorption Process in body & Role of Vitamin C as Reducing Agent in word/ .doc / .ppt Format

Iron Absorption

Ease with which this varies depends upon whether the iron is haem iron or non-haem iron. Haem iron is easily absorbed. Most of the non haem iron is ferric (Fe+++) iron and is insoluble.

For absorption, it has to become soluble and ferrous (Fe++) iron. Gastric HCl makes the iron soluble and vitamin C (a strongly reducing agent) converts ferric into ferrous iron.Thus, persons whose stomach has been removed or persons deficient in vitamin C suffer from iron deficiency.

What are Iron Rich Foods

Health Care Guide on Diet / Good High Iron Content Foods Sources for vegetarian & Non Vegetarian

Iron as a Nutrient

Source, Daily requirement, Absorption, Transport and Intake Regulation of Iron

Liver, Heart, Kidney, Egg yolk (all animal foods) are exce­llent sources.

Meat and Fish also are also good sources of Iron.

Milk, particularly cow's milk is well known for its iron defici­ency. Green vegetables are good sources but non-green vegetables are deficient in iron. Vegetables contain phytic acid and phosphates which retard iron absorption.

Role of Iron in Human Body

Presentation notes on Importance & Function of Iron in Human Body for Students & kids in word/ .doc/ .ppt Format

Why Iron Is needed?

Life span of RBC, normally, is about 120 days. After 120 days, the RBC dies and iron of the Hb, within the RBC, is ultimately extracted → stored → reutilised to form Hb (recycling of iron). Viewed in this way, iron, apparently need not be supplied through food because iron is preserved. But this is not so because:

Iron Metabolism in the Body

Presentation Notes on Iron Metabolism for Medical Biology Students in word/ ppt Format

IRON METABOLISM

Iron containing substances in our body :-

Two sets of iron containing compounds are found in our body:

(1) Essential iron containing compounds. These are essential compounds in our body  and they have iron as one of the component parts. Examples: Hb, some en­zymes like cytochrome catalse, peroxidase, xanthine oxidase and soon.