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  1. -Iron is one of the essential trace elements for life – Found in the body in two different forms, namely the functional (essential ) and storage forms 1-Functional iron .Serves metabolic or enzymatic function .Mediates its physiological function through iron containing proteins . including iron containing non enzymatic proteins (hemoglobin and myoglobin) 2-Storage iron – Primarily as ferritin and hemosiderin – Responsible for the maintenance of iron homeostasis
  2. • Physiological functions – Iron plays a vital role in • Binding and transport of oxygen • Electron transfer reactions • Gene regulation • Regulation of cell growth and differentiation • Immune function • Energy metabolism and • Cognitive function
  3. • of iron – Despite its abundance in the earth’s crust, iron deficiency is a common occurrence in both the developing and developed world. Sources of Iron – Iron in the diet comes from • Plants – Non heme iron • Animal sources – Heme iron legumes, and whole and enriched grains are good sources of non- heme iron
  4. • Dietary sources and forms of iron – Heme iron (eg: hgb and mgb) • From animal products like : meat, egg, • 50-60% of iron in body is heme • Absorbed into the enterocytes as intact porphyrin complex • and is little affected by the composition of meals and the GI secretions – Non-heme iron (eg: Ferric form, Fe3+) • From plant products (leafy green vegetables) • 40% of iron in body • enriched products • Must be solubilized and ionized by the acid gastric juice and • reduced to the ferrous form (Fe2+) prior to absorption from the luminal to the mucosal phase
  5. -Non heme iron absorption is affected by many factors(Inhibitors) .Phytic acid (phytates), polyphenols, tannins, heavy metals, fibers, low altitude, replete stores, achlorhydria • Phytate which is extensively present in cereals and legumes is the major factor responsible for the poor bioavailability of iron in these foods • Tannins present in black tea are the most potent of all inhibitors of iron absorbition • Calcium consumed in dairy products such as milk or cheese can inhibit iron absorption
  6. Enhancers -Soaking, fermentation and germination of these food grains improve absorption by activating phytases to degrade phytic acid - ascorbic acid, amino acids, high altitude, HCl, fermentation, alcohol, deficient stores - Both ferric and ferrous salts are present in the diet but only the ferrous salts are absorbed from the gastrointestinal tract Ferric compounds must be reduced in the gastric juice in order to be absorbed.
  7. • Interaction with other micronutrients • Absorption and bioavailability of iron can be influenced by a number of factors • Negative effects on zinc indices have been reported after iron supplementation • Ascorbic acid predicts has a strong promoting effect over absorption- non-heme iron and reducing ferric (Fe3+) to ferrous (Fe2+) iron, requirements for the uptake of iron into the mucosal cells • Interactions have also been recognized with retinol.
  8. – Occurs when hgb production is considerably reduced leading to a fall in its levels in the blood – Although most anemia is due to iron deficiency, – Iron depletion can be categorized into three stages Stage I: Iron depletion stage Stage II: Iron deficient erythropoiesis Stage III: Iron deficiency anemia
  9. • Stage I: Iron depletion stage – Characterized by a progressive reduction in the amount of iron storage in the liver – At this stage, the supply of iron to the functional compartment is not compromised – So, levels of transport iron and hemoglobin are normal • Stage II: Iron deficient erythropoiesis – Also called iron deficiency without anemia – Characterized by the deterioration of iron stores – Iron supply to the erythropoietic cells is progressively reduced – and decreases in transferrin saturation occur
  10. • Stage III: Iron deficiency anemia – Final stage of iron deficiency – Characterized by the exhaustion of iron stores, – declining levels of circulating iron and – presence of frank microcytic, hypochromic anemia The main feature of this stage is - a reduction in the concentration of hemoglobin in the red blood cells arising from the bone marrow – Decrease in the hematocrit and red cell manifestation also occur
  11. – The main causes for failure to meet iron needs could be • Dietary – Inadequate intake of both heme and non-heme iron rich diets – Regular consumption of high phytate plant-based meals – Inadequate intake of iron absorption enhancers e.g. vit A, B- 12, folic acid, & possibly B-6 • Non dietary – Increased physiological requirements such as menstruation – Frequent parasitic infections including -Malaria -Hookworm -Trichuriasis -Schistosomiasis -Abnormal blood cell production (sickle cell)
  12. • Who is at the greatest risk? • Children 6-24 months • Special risk infants: low birth weight, premature, and/or from anemic mothers • Women of reproductive age, especially pregnant women • Adolescents (especially females) • PLWHA – IDA affects more than 2 billion people in the world.
  13. • Iron nutritional status can be assessed by the following biochemical and hematological tests – Hemoglobin – Hematocrit – Serum iron concentration • Hemoglobin (Hgb) • Measurement of Hgb is probably the most widely used test for IDA • Cut off points for hemoglobin values for the diagnosis of anemia: • for adult and children >6years 12 g/dl, • for pregnant mothers and children <6 years 11g/dl
  14. • Hematocrit(hct) – Volume fraction of packed red cells – In IDA, hct falls after hgb formation has become impaired* – Hct below 33% is cut offs used to define anemia • Limitations of hct and hgb determination – Poor sensitivity – Poor specificity – Poor precision
  15. – IDA is associated with • Poor reproductive performance • High proportion of maternal death (10 – 20% of total deaths) • High incidence of LBW (< 2500 g at birth) • Intrauterine malnutrition • Impaired scholastic performance (impaired psychomotor development and intellectual performance) • Decreased resistance to infection • Reduction of work capacity/productivity (10% decrease in hemoglobin = 15% decrease in productivity)
  16. Prevention and treatment guidelines for iron supplementation  Pregnant women -Prevention 60 mg iron + 400 μg folic acid (FA) daily for 6 month in pregnancy -Treatment of severe anemia 120 mg iron + 400 μg folic acid daily for 3 months  Children 6-24 mo - Prevention 12.5 mg iron + 50 μg folic acid daily from 6-12 mo of age or from 2-24 mo of age if LBW -Treatment of severe anemia – 25 mg iron + 100-400 μg of folic acid daily for 3 months Children 2-5 yr : 20-30 mg iron – Deworming: Where hookworm is endemic, give antihelminthic
  17. • Prevention and control of IDA – The basic principles in the prevention of IDA are ensure regular consumption of iron to meet the requirements of the body and – to increase the content and bioavailability of iron in the diet – There are four main approaches • Provision of iron supplements • Fortification of commonly consumed foods with iron • Nutrition education • Horticulture based approaches to improving the iron bioavailability of common foods
  18. • Iron supplementation • The essential principle of management of IDA is iron replacement therapy • and treatment of the underlying causes such as parasitic infections or gastrointestinal bleeding – Common side effects of iron supplementation are nausea, constipation, black stools and even diarrhea • Provide iron or IFA to pregnant women & children 6-24 months – If resources permit, provide IFA to other vulnerable groups such as lactating women, school-age children & adolescents
  19. • Fortification • Foods successfully used as vehicles for food fortification are wheat, bread, milk powder, salt, infant formula and sugar – Sweden: wheat flour (65 mg/kg) – USA : wheat flour (44 mg/kg) – India: common salt • Nutrition education • The only sustainable solution to IDA is to help the communities to – Consume regularly foods that are rich in iron – Encourage intake of promoters of iron absorption such as vitamin C – Discourage high consumption of inhibitory factors