Trace minerals

Question 1

Fe

Answer 1

50% stored as Hb
50% storage Fe (w/ ferritin)
Transferrin binds Fe for transport in blood–no “free” iron, as it is highly oxidizing and causes oxidative damage
Involved in DA synthesis, myelination, electron transport chain cytochromes

Question 2

Fe sources

Answer 2

Heme–red meat

non-heme–legumes, nuts, whole grains, fortified food products

Question 3

Phytic acid

Answer 3

Storage form op phosphorous in plants
present in consumed plant materials, binds Zn, Fe, Ca to limit gut absorption
humans don’t possess phytase enzyme

Question 4

Fe absorption

Answer 4

Ascorbic acid (Vit C) reduces Fe to aid absorption
Fe deficiency --> decreased liver hepcidin          -->increased absorption
inflammation --> increased hepcidin                     -->decreased absorption

Question 5

Fe def. RFs

Answer 5

premature baby, poor intake, pregnancy, hemorrhage, obesity (inflammation–>decreased abs.), bariatric surgery

Question 6

Fe deficiency Sx

Answer 6

Fatigue, shyness, irritability, attention deficit
Impaired growth and brain development
Microcytic, hypochromic anemia

Question 7

Fe toxicity

Answer 7

potent pro-oxidant

caused by: hemorrhage, shock, liver failure, hereditary hemochromatosis (hepcidin defect –>increased absorption)

Question 8

Zn

Answer 8

Cofactor for conversion of ALA to porphobilinogen, modulation of hormones and neurotransmitters
involved in sexual maturation, immune function, wound healing

Question 9

Zn sources

Answer 9

Beef>poultry>fish
absorption inhibited by phytate
unlike Fe, absorption is not increased by deficiency
Crude control of Zn level by absorption–excretion/secretion fine tune level

Question 10

Zn deficiency

Answer 10

Acrodermatits enteropathica (AR defect in Zn absorption)
deficient intake
both lead to stunting, hypogonadism, delayed sexual maturation, acro-orofacial dermatitis, diarrhea
affects taste buds –> decreased appetite/anorexia
Supplementation decreases diarrhea, pheumonia, and childhood death