Minerals Flashcards
what is the recommended dietary allowance (RDA) of iron for male vs female adults?
males (19-30): 8mg/day
females (19-30): 18mg/day
which vitamin plays a key role in non-heme iron bioavailability?
vitamin C
also citric acid and lactic acid
Plummer-Vinson syndrome
triad of esophageal webs + glossitis + iron deficiency anemia
all due to iron deficiency
hereditary hemochromatosis
AR mutation in HFE gene —> increased iron absorption, iron toxicity
—> liver cirrhosis, “bronze diabetes” (ROS damage to pancreas), cancer risk, sexual dysfunction, arthritis
what are some dietary sources of copper? (name a few)
oysters, kale, mushrooms, sesame seeds, cashews, chickpeas, chocolate, avocados, goat cheese
how is copper absorbed in the GI tract?
copper absorbed from duodenum (proximal GI tract)
ingested as oxidized form (Cu2+) but must be reduced to be transported across apical membrane of enterocytes
what type of environment increases the bioavailability of cooper absorption in the GI tract?
acidic environment
what 2 carrier proteins are responsible for transporting copper? to what is copper bound within cells?
- albumin - enteric circulation to tissue
- ceruloplasmin - liver to tissue (copper is stored in liver)
within cells, copper is bound to protein metallothionein
what is copper used for? (3)
- collagen formation (lysyl oxidase)
- superoxide dismutase cofactor (ROS —> hydrogen peroxide)
- monoamine oxidase cofactor (inactivation of neurotransmitters)
Menke’s disease
XLR mutation in ATP7A needed to transport copper across cell membranes —> copper deficiency
symptoms: wiry silver hair, poor growth, hypotonia
Wilson’s disease
AR mutation in ATP7B required for copper transport in the bile and incorporation into ceruloplasmin —> copper toxicity
copper accumulates in basal ganglia —> Parkinsonism, psychosis, Kayser-Fleischer rings in cornea
[can treat with zinc - interferes with copper bioavailability]
what are some dietary sources of zinc?
shellfish, cashews, garbanzo beans, yogurt, meat
what are 3 lifestyle habits that increase zinc LOSS?
- alcoholism
- lactating
- heavy smoking
AR mutation in zinc membrane transporter protein within enterocytes in the duodenum/jejunum, resulting in peri-orificial and peri-anal dermatitis + alopecia + diarrhea
acrodermatitis enteropathica —> zinc deficiency
where does selenium come from?
seafood, meat, grain, brazil nuts
{depends on the selenium content in the soil}
what is the storage vs active form of selenium?
storage: selenomethionine (liver, pancreas, muscles, kidneys, thyroid)
active: selenocysteine
selenium is essential for… (3)
- antioxidant enzymes (glutathione peroxidase, etc)
- thyroid function
- immune function
Keshan disease
due to selenium deficiency
dilated cardiomyopathy + loss of appetite (anorexia) + nausea
what are the symptoms of iodine deficiency seen in babies? in adults?
babies - bloated bellies, pale, umbilical hernia, protuberant tongue, impaired brain development
adults - goiter, hypothyroidism
where does chromium come from, and what is it used for?
egg yolks, whole grains, nuts, mushrooms
enhances insulin action (deficiency causes high blood glucose after meals)
where does cobalt come from and what is it used for?
animal food containing vitamin B12, functions as constituent of vitamin B12
deficiency presents the same as B12 deficiency
