Iron

Question 1

What are the 3 forms of Iron

Answer 1

Functional, Transport and Storage

Question 2

What are Functional Iron forms

Answer 2

Hemoglobin, Myoglobin, Heme enzymes, Nonheme enzymes

Question 3

What is the Transport Iron form

Answer 3

Transferrin

Question 4

What are the Storage Iron forms

Answer 4

Ferritin and Hemosiderin

Question 5

How much Storage Iron is common in Men

Answer 5

12mg/kg

Question 6

How much Storage Iron is common in Women

Answer 6

4mg/kg

Question 7

Why do women have so little Storage Iron

Answer 7

Menstruation

Question 8

What is Functional Iron

Answer 8

Iron in molecules, doing something

Question 9

What is Transport Iron

Answer 9

Iron in transit, available for use

Question 10

What is Storage Iron

Answer 10

Iron bound to Protein (Ferritin), stored in liver and blood proportional

Question 11

How much Hemoglobin is common in Men

Answer 11

31mg/kg

Question 12

How much Hemoglobin is common in Women

Answer 12

28mg/kg

Question 13

What are Iron containing enzymes

Answer 13

Monooxygenases and dioxygenases

Question 14

Why is most Iron in body bound to protein

Answer 14

Highly reactive metal, bound to keep from oxidizing

Question 15

What enzyme requires Copper as a cofactor

Answer 15

Hephaestin

Question 16

What forms of Iron do we eat

Answer 16

Heme and nonheme

Question 17

What is the first step in heme-iron digestion (Hemoglobin/Myoglobin)

Answer 17

Proteases (from pancreas) free heme from globin in lumen

Question 18

What is the next step in heme-iron absorption after globin is cleaved off

Answer 18

Heme has own receptor on brush border

Question 19

What is the next step in heme-iron absorption after heme receptor

Answer 19

Heme oxygenase frees Iron from heme as Iron2+: Ferrous iron

Question 20

What is the next step in heme-iron absorption once in Fe2+ form

Answer 20

Ferroportin: Transport protein on basement membrane transports out into blood and oxidizes into Ferric form (Fe3+)- enzyme Hephaestin hen binds to Transferrin

Question 21

What is the first step in nonheme-iron (Fe3+) absorption

Answer 21

Reductase at brush border reduces to Fe2+ form

Question 22

What transports reduced nonheme-iron (Fe2+) at brush border

Answer 22

DMT1

Question 23

What binds to iron, inhibiting absorption

Answer 23

Polyphenols and Phytic acid: tea, wine, chocolate and coffee

Question 24

What is the RDA for Iron in Men

Answer 24

8mg

Question 25

What is the RDA for Iron in Women

Answer 25

18mg

Question 26

What is the UL for Iron

Answer 26

45mg

Question 27

What are food sources of Iron

Answer 27

Beef liver, beef, dark meat poultry, oysters, leafy greens, fortified cereals, dark chocolate, tofu, walnuts

Question 28

What is the absorption % for nonheme iron

Answer 28

8-10%

Question 29

What is the absoprtion % for heme iron

Answer 29

15-18%

Question 30

What nutrients Enhance absorption of Iron

Answer 30

Sugars (fructose, sorbitol), Acids (citric, lactic, ascorbic), meat (heme iron)

Question 31

What nutrients Inhibit absorption of Iron

Answer 31

Calcium, Zinc, Magnesium: Competition in Multivitamins; Polyphenols, Phytates, Oxalic Acid

Question 32

How much Iron is lost everyday

Answer 32

1-2mg

Question 33

How much Iron must be absorbed everyday

Answer 33

1-2mg; replace what is lost

Question 34

What are the stages of Iron deficiency

Answer 34

Normal - Early Negative Iron Balance - Iron Depletion - IronDeficient Erythropoiesis - IronDeficiency Anemia

Question 35

At what stage of Iron deficiency would it be ideal to catch symptoms

Answer 35

Iron depletion

Question 36

How is Iron status measured

Answer 36

Serum Ferritin

Question 37

What is the first Iron function to deplete

Answer 37

Storage

Question 38

What is Hematocrit (Hct)

Answer 38

% packed cell volume

Question 39

What are symptoms for RBCs during Iron deficient anemia

Answer 39

Microcytic, Hypochromic