Macromineral iron - Introduction, Biochemical role, Recommended dietary Allowance of iron, dietary sources of iron, Deficiency diseases of iron - Hemochromatosis, hemociderosis.

1. Iron - Biochemical Role, RDA
and Deficiency Diseases

3. Iron - Introduction
• The total content of iron in the adult body is 3-
5 g.
• About 70% of this occurs in the erythrocytes
of blood as a constituent of hemoglobin.
• Atleast 5% of body iron is present in
myoglobin of muscle.

4. Iron - Introduction
• Heme is the most predominant iron-containing substance.
• It is a constituent of several proteins/enzymes
(hemoproteins) - hemoglobin, myoglobin, cytochromes,
Xanthine oxidase, catalase, tryptophan pyrrolase,
peroxidase.
• Certain other proteins contain non-heme iron e.g.
transferrin, ferritin, hemosiderin.

6. Iron – Biochemical Functions
I. Iron mainly exerts its functions through the
compounds in which it is present.
o Hemoglobin and myoglobin are required
for transport of O2 and CO2.

10. Iron – Biochemical Functions
II. Cytochromes and certain non-heme proteins
are necessary for electron transport chain
and oxidative phosphorylation.

12. Iron – Biochemical Functions
III. Peroxidase, the lysosomal enzyme, is
required for phagocytosis and killing of
bacteria by neutrophils.

15. Iron – Daily Requirements
 Adult men - 10 mg/day
 Menstruating woman - 18 mg/day
 Pregnant and lactating woman - 40 mg/day

17. Iron - Sources
 Rich sources - Organ meats (liver, heart,
Kidney)
 Good sources- Leafy vegetables, pulses, cereals,
fish, apples, dried fruits, molasses.
 Poor sources - Milk, Wheat, Polished rice.

19. Iron – Disease states
I. Iron deficiency anemia: This is the most prevalent
nutritional disorder worldover, including the well
developed countries (e.g.USA).
 Several factors may contribute to iron deficiency
anemia.
 These include inadequate intake or defective
absorption of iron, chronic blood loss, repeated
pregnancies and hookworm infections.

20. Iron – Disease states
• Strict vegetarians are more prone for iron
deficiency anemia.
• This is due to the presence of inhibitors of iron
absorption in the vegetarian foods besides a
relatively low content of iron.

21. Iron – Disease states
• Iron deficiency anemia mostly occurs in growing children,
adolescent girls, pregnant and lactating women.
• It is characterized by microcytic hypochromic anemia with
reduced blood hemoglobin levels (<12 g/dl).
• The other manifestations include apathy ( dull and
inactive) sluggish metabolic activities, retarded growth and
loss of appetite.

24. Iron – Disease states
II. Hemosiderosis: This is less common disorder and is
due to excessive iron in the body.
• It is commonly observed in subjects receiving repeated
blood transfusions over the years e.g. patients of
hemolytic anemia, hemophilia.
• As already stated, iron is a one-way compound.
• Excessive iron is deposited as ferritin and
hemosiderin.

25. Hemosiderosis patients – Iron Accumulation

26. Iron – Disease states
III. Hemochromatosis: This is a rare disorder
in which iron is directly deposited in tissues
(liver, spleen, pancrease).
• Hemochromatosis, sometimes causes a
condition called bronze diabetes.

28. Hemochromatosis - Symptoms