Iron Flashcards
where are heme iron found and how is it absorbed
heme iron is found in animal products, part of hemoglobin, absorbed by using heme carrier protein 1
where are non heme iron found and how is it absorbed
non heme iron is found in plants and supplements; reduced in the SI (requires vit C) absorbed using generic divalent mineral transporter
heme iron absorption
- absorbed by facilitated diffusion using heme carrier protein 1; 2. Fe2 released inside enteroyte by heme oxygenase
nonheme iron digestion
ferrous iron is aborbed by facilitated diffusion using divalent mineral transporter
what increased Iron absorption
fructose and sorbitol, acids, meat poultry and fish
what decreases iron absorption
coffee and tea, phytate (whole grains), oxalate (veggies), phosvitin (egg whites), Ca, Zn, Mn, Ni
iron is extremely reactive so it must be bound?
protein at all times
if the body doesnt need iron right away by what in the enterocyte
ferritin. if not used in 2-3 days its sloughed off with lining of SI
if the body needs iron it is bound to ____ and transport across the basolateral membrane and oxidized to ?
bound by ferroportin and oxidized to Fe3+
Transferrin picks up Fe3+ and transports it to
liver spleen and bone marrow
iron is made into?
hemoglobin or myoglobin
if iron is stored it binds to _____? where is it stored?
liver, spleen and bone marrow
ferritin location and function
located in SI, liver, spleen, bone marrow Function: iron stores
ferroprortin location and function
Location: SI
Function: transports Fe across the basolateral membrane
ferroportin requires ____ to transport Fe across the basolateral membrane
Copper
Transferrin location and function
Location: Plasma
function: transports Fe in plasma
When iron stores are low what protein takes t out of the SI
transferrin
When iron stores are high what keeps it in the SI
ferritin
iron RDA men and woman
men: 8mg/day
woman: 18mg/day
sources of Iron
seafood, lean meat, poultry, legumes, vegetables, black strap molasses, dried fruit, whole grain bread
is iron deficiency most common nutritional deficiency in the US
yes
who is at risk for Fe deficiency
Kids, adolescents, females of childbearing age, pregnant woman
symptoms of iron deficiency
pallor, fatigue, decreased cognition, short attention span, depressed immune system
iron supplements can cause a depletion in _____
zinc
TUI of iron
40-45mg/day
whos is at risk of iron toxicity
supplemental iron overdose in kids
genetic disorder-hemochromatosis
iron toxicity causes
organ damage from iron deposition
what is hemochromatosis
toxic build up of iron due to genetic inability to properly metabolize it
which carrier protein is synthesized in both the SI and Liver
ferritin
what compound in chocolate decreases iron absorption
oxalate
when a patient presents with an iron deficiency which blood protein is elevated
transferrin
what mineral deficiency may lead to an iron deficiency
copper
