Week 7: Iron (from slides 13-33)

Question 1

What are the different kinds of anemia?

Answer 1

microcytic & hypochromic (with diminished O2 transport)

Question 2

How does iron deficiency impact physical performance?

Answer 2

decreased performance during physical exertion (cytochromes)

Question 3

How does iron deficiency impact children?

Answer 3

fatigue, impaired psychomotor performance, decreased responsiveness

Question 4

What are the impacts of anemia (iron deficiency)?

Answer 4

• impaired adaptation to cold
  -reduced immune function
  -increased lead absorption (pica)
• low birth weight and preterm delivery (pregnancy)

Question 5

What should be suspected in men and women for iron deficiency?

Answer 5

women: suspect diet/menstruation
men: suspect other factors (disease)

Question 6

What causes iron deficiency in developing countries?

Answer 6

low intake of meat, fish, poultry (heme iron)

Question 7

What percentage of children have iron deficiency in developing countries?

Answer 7

50-80%

Question 8

What is a challenge of iron supplements in developing countries?

Answer 8

beware of feeding parasites- metabolize on iron

Question 9

Explain the order/process of iron deficiency in the body

Answer 9

depletion in
1. iron stores
2. iron in plasma (low in circulation)
3. iron in RBCs (while retaining some in plasma)

Question 10

What are the risks of excess iron?

Answer 10

-hemochromatosis (genetic)/bronze diabetes
-arthritis
- cirrhosis
- heart failure

Question 11

How to treat excess iron?

Answer 11

phlebotomy (drawing blood from vein)

Question 12

What are the risks of excess iron (population level)? What should you avoid to prevent excess iron?

Answer 12

-related to free radicals, LDL peroxidation (insulin resistance)
- high ferritin association- increased risk of cancer and Ml

• avoid alcohol, excess iron intake/supplements

Question 13

What is the UL of iron?

Answer 13

45mg/day (side effects)

Question 14

What are the iron requirements for women under 50 years old?

Answer 14

RDA 18mg, EAR 8mg

Vegetarians 32mg

Question 15

What are the iron requirements for women over 50 years old?

Answer 15

RDA 8mg, EAR 5mg

Vegetarians 14 mg

Question 16

What are the iron requirements for men?

Answer 16

RDA 8mg, EAR 6mg

Vegetarians 14 mg

Question 17

When should a person have higher iron intake?

Answer 17

pregnancy, lactation, in children
(growth)

Question 18

What is the lifespan on RBCs?

Answer 18

120 days/ when its damaged

Question 19

What accounts for the largest use of functional iron in the body?

Answer 19

heme synthesis

Question 20

RBCs contain what percent of total body iron?

Answer 20

2/3 of total body iron

Question 21

Where does heme synthesis occur?

Answer 21

In RBCs of bone marrow

Question 22

What is the function of catalase?

Answer 22

(enzyme) protects cells from oxidative damage from free radicals

Question 23

Which form of iron is more readily absorbed?

Answer 23

heme iron

Question 24

What is heme iron derived from?

Answer 24

hemoglobin and myoglobin (animal sources)

Question 25

Where is iron stored in the body? In what form?

Answer 25

spleen, liver, bone marrow in ferritin (storage protein) form-not stable

Question 26

What form does iron take for long term storage?

Answer 26

hemosiderin (storage protein)

Question 27

Is dietary iron able to meet body needs?

Answer 27

no :)

Question 28

What is the difference between microcytic and macrocytic anemia?

Answer 28

micro: smaller RBCs, not enough hemoglobin macro: immature RBCs, large, may contain nucleus, low hemoglobin levels

Question 29

What can mask low iron stores?

Answer 29

serum ferritin rises due to inflammation

Question 30

What is hematocrit?

Answer 30

portion of blood volume that's RBCs