Exam 3: Trace Minerals Flashcards
Major minerals require
> 100 mg/d
Trace minerals require
<100 mg/d
Iron is mostly found in
Hemoglobin (69%) and myoglobin (8%)
Women store _____ iron than males
Less
Iron is easily _______ and reused daily
Recovered (90%)
We must get _____% of iron from our diet
10%
Iron is extremely
Oxidative… if free can cause oxidative reactions to occur (toxic)
Iron-binding proteins
Ferritin, ferroportin, transferrin
Ferritin is found in _____________ and functions as a
SI, liver, spleen, and bone marrow
Iron store
Ferrroportin is located in the ________ and functions to
SI; transport Fe across basolateral membrane, requires copper
Transferrin is located in the ____ and functions to
Plasma; transports Fe in plasma
Iron function in hemoglobin synthesis
Part of heme and acts as carrier for oxygen (also part of myoglobin)
Iron function in metabolism
Cofactor for cytochromes (ETC and phase I detox enzymes), glucose metabolism, collagen and purine synthesis, catalase
Catalase is a
Antioxidant enzyme
Peroxide enzymes found in peroxisomes of cell and WBCs
Catalase (CAT) and Myeloperoxidase
- both require iron
Only mineral that female have a higher requirement than males
Iron (because of mensuration)
1 nutritional deficiency world wide
Iron
Vegetarians require _____ times the RDA of iron
1.8
Sources of iron
Liver and other organ meats Seafood Lean meat Poultry Legumes Vegetables Black strap molasses Dried fruit Whole grain or enriched breads
Full-term babies are born with _______ of iron stores if their mom is not deficient
4 months
Bad sources of iron
Milk and dairy product
Corn and other starchy veggies
High fiber, phytate or oxalate-containing foods
Largest source of iron in the US
Iron fortified breakfast cereal Bread Cakes Cookies Donuts
We absorb more ______ than _____
Heme than nonheme
Heme iron is found in
Animal products
Hcp1 absorbs
Heme iron ONLY
iron found in plants and supplements
Nonheme iron
Nonheme iron is found in __ form and reduced in the ______
Salt form; reduced in SI (requiring vit C)
Nonheme Irvine is absorbed by
Generic diva lent mineral transporter
Heme is absorbed by _______ _________ usingheme carrier protein 1
Facilitated diffusion
Iron is released inside enterocyte by
Heme oxygenase
Ferric iron is
3+ and found in plants and supplements
Ferrous iron is absorbed by _____ ________ using diva lent mineral transporter (DMT)
Facilitated diffusion
Things that increase iron absorption
- fructose and sorbitol
- acids (ascorbic, citric, lactic, tartaric)
- meat, poultry, fish
Things that decrease iron absorption
- polyphenols in coffee and tea
- phytate (whole grains)
- oxalate (tea, veggies, chocolate)
- phosvitin (egg yolks)
- Ca, Zn, Mn, Ni
Percentage of nonheme iron absorbed
2-10%
Percentage of heme iron bioavailable
20-30%
Iron absorption depends on
Growth state
Dietary contents
Other minerals
Iron must be bound to a. ____ at all times because it is extremely _____
Protein; reactive
If body needs iron it is transported across the basolateral membrane b
Ferroportin (oxidized to Fe+)
Transferrin picks up Fe ___ and shuttles it to ____, ____,, and _____
3+, liver, spleen, and bone marrow
Hepcidin
Peptide hormone produced in liver
Hepcidin binds to ______ and prevent transport of _______ across basolateral membrane
Ferroportin, iron
Inflammatory conditions _________ iron absorption
Decrease
Most common nutritional deficiency in US
Iron
Iron deficiency can be found with and without
Anemia
Who’s is at risk of iron deficiency?
- infants less than2
- adolescent girls
- females of childbearing age
- pregnant women
- vegetarians
Symptoms of Fe deficiency
Pallor, fatigue, decreased cognition, short attention span, depressed immune system
Causes of iron deficiency anemia
- low Intake
- excessive blood loss
- achlorhydria
- consumption of binders
- GI lesions decreasing absorption
TUL for iron
40-45 mg/day
People at risk for iron toxicity
Supplemental overdose in kids Genetic disorder (hemochromatosis Transfusion overload
Hemochromatosis and transfusion overload cause a _______ in exciting levels
Decrease
Symptoms of iron toxicity
Organ damage from iron deposition, GI bleeding, shock, metabolic acidosis
Hemochromatosis
Genetic defect in how a person gets rid of iron
Contraindications for iron supplementation
- postmenopausal women
- older males
- alcoholics
Iodine is important for
Thyroid hormones
-required for synthesis of T4 and T3
Sources of iodine
Iodized salt
Seafood
Dairy
Fruits and veggies (depending on soil)
How many iodine’s are on thyroxine?
4
How many iodine’s are on triiodothyronine
3
Higher iodine requirements for
Pregnant and lactating females
Only ____ of salt sold is iodized
50%… iodinization is not mandatory in the US
Proteins that bind iodine and prohibit absorption
Found in cabbage, turnips, soy, peanuts, cassava
*issue in thyroid disorders
Who is at risk of iron deficiency?
Those in developing nations
Low ____ causes pituitary to secrete TSH and leads to ____
T4; hyperplasia (goiter)
Iodine deficiency is the #1 cause of preventable _____ ______ worldwide
Brain damage
Iodine deficiency can cause
Cretinism Congenital hypothyroidism Goiter Impaired mental and physical development Hypothyroidism
Iodine in cretinism
Deficiency in utero because mom gets the 1st dibs on iron
Congenital hypothyroidism is a ___ ____ caused by iodine deficiency
Genetic defect
Milk iodine deficiency in utero can lead to
Decrease in IQ
Long term deficiency of iron in childhood or adolescence can cause
Delayed growth or sexual maturation
Symptoms of iodine toxicity
Iodine-induced hyperthyroidism, iodine-excess goiter, autoimmune thyroiditis, hypothyroidism
Zinc functions
- synthesis DNA, RNA, and protein
- immune system
- synaptic neurotransmission
- folate digestion (conjugase)
- macronutrient metabolism
- brown growth (alkaline phosphates)
Zinc dependent enzyme needed to remove ____________ to digest _______
Glutamic acid residues; folate
Inhibitors of conjugase
Legumes, oranges, cabbage, chronic alcohol consumption
Superoxide dismutase (SOD) requires
Zinc and copper
SOD1 is found
In cytosol
SOD3 is found
Extra-cellular
Superoxide dismutase is a
Antioxidant enzyme
Best source of zinc
Oysters
Sources of zinc
Seafood Meat (70% in SAD- red meat) Legumes Dairy Fortified cereals
Common symptoms of zinc deficiency
Diminished taste mechanism (hypotension)
Decreased growth
Impaired immune function (decreased # of NK cells)
Less common zinc deficiency symptoms
Poor wound healing
Delayed sexual maturation (hypogonadism in males)
diarrhea
Why don’t we get enough zinc?
- dietary fiber intake
- iron to zinc ration >3:1 in supplements
- vegetarian diets contain less bio available zinc
- needed to synthesize transport proteins for iron and vitamin A
People as risk for zinc deficiency
- Malabsorptive conditions
- alcoholics (30-50%)
- Vegetarians
- Pregnant/ lactating women
- Exclusively breastfed infants >6 months
- those with sickle cell anemia
Zinc toxicity symptoms
Anemia, fever, metallic taste, headache, nausea, vomiting, copper deficiency
Selenium function
Cofactor (selenocysteine or selnomethionine)
Selenium is required for
Glutathione peroxidase
Selenium converts
T4 to T3
Sources of selenium
Brazil nuts Seafood Meat (pork, poultry) Whole grains Highly dependent on soil content
Who is at risk for selenium deficiency?
People living in china
What causes Keshan’s disease?
Selenium deficiency and a Coxsackie virus
Symptoms of Keshan’s disease
Cardiomyopathy in children and women
What causes Kachin-Beck’s disease?Symptoms?
Virus + Se deficiency
Stiffness, swelling and pain in finger joints and osteoarthritis
Selenosis
Se toxicity
Hair and nail brittleness, tooth decay, GI upset, mutagenic, can be lethal
Fluoride used to
Prevent dental caries
How fluoride prevents dental caries
- facilitates crystallization of calcium and phosphorus as fluoropatite
- promotes repair and remineralization
- reverses decay process
- decreases growth of microorganisms in the mouth
Sources of fluoride
- fluoridated water
- fluoridated toothpaste
- tea (black>green>white)
- grape juice, raisins
- crab, shrimp
Fluoridation has decreased cavities by
> 50%
Fluoride deficiency
People who consume well or bottled water at risk
- risk of dental Aries
Fluorosis
Fluoride toxicity
Symptoms of fluorosis
Chronic: mottling of teeth, pitting of bones
Acute: nausea, vomiting, diarrhea, heart arrhythmias, death
Kids and supplement users at risk
Copper is found in high concentrations in
Liver, brain, heart and kidney
Ceruloplasmin
90% of copper in serum is a part of this glycoproteins, oxidative enzyme
Copper function cofactor
Metalloenzyme
Metalloenzyme is required for
- iron transport out of the enterocyte
- metabolism of superoxide, catecholamiens , serotonin
- synthesis of ATP, hemoglobin and peptide hormones
- Cross linking of collagen
Cytochrome C contains _____ copper atoms per molecule
3
Major sources of copper
Liver and oysters
Sources of copper
Liver oysters Nuts and seeds Legumes Cocoa (Major source in US) Meat
Genetic disease found with copper deficiency due to copper malabsorption and excessive urinary loss
Menkes syndrome (AKA Kinky-hair syndrome)
Symptoms of copper deficiency
Anemia, depigmentation of skin and hair, bone demineralization, neutropenia (impaired immunity- best early indicator)
Copper toxicity is ______ and symptoms include:
Rare
- nausea, vomiting, gastric pain, liver damage, kidney damage (little to no urine output)
Wilson’s disease is caused by
Copper toxicity
In Wilson’s disease copper accumulates in
Liver, brain, kidneys and eyes
Symptoms of Wilson’s disease are usually seen ________ of age and cause
> 7 years of age
Kayser- fleischer rings around cornea
Manganese used as a cofactor
- used by enzymes in mitochondria
- formation of con and skeletal tissue
- growth
- reproduction
- SOD2
Manganese can replace _____ when low
Magnesium
Manganese- SOD is found in
Mitochondria
Sources of manganese
Whole grains Legumes Nuts Coffee Tea
Symptoms of Mn deficiency
Decreased reproduction and growth, skeletal abnormalities
Mn toxicity
Liver and brain damage, neurological abnormalities, tremors (Parkinson’s like), memory impairment
**only seenin miners inhaling Mn dust
Molybdenum functions as a cofactor in
Xanthine oxidase
Xanthine oxidase converts
Hypoxanthine to uric acid
- purine metabolism and gout
Chromium functions with _____ secretion and binding
Insulin
Highest levels of chromium found in
Yeast
Oysters
Liver
Potatoes
Moderate levels of chromium found in
Seafood
Whole grains
Meat
Cheese
Poor sources of chromium
Dairy (breast milk included)
Fruits
Veggies
Amount of chromium absorbed
<2%
Symptoms of insulin deficiency
Insulin resistance, high plasma fret fatty acid concentrations
Chromium supplementation
Controversial: mixed results as an aide for diabetic patients
- Hexavalent form has been shown to cause DNA damage
Chromium toxicity
Not likely to be toxic from food (No TUL)
Body water functions
Solvent
Transport
Thermoregulation
Lubricant
The body requires ____ mL/Cal of water for metabolism
1 mL/Cal
Chronic dehydration can cause
Renal infections
Kidney stones
Gallstones
Constipation
Water intoxication AKA
Hyponatremia
Hyponatremia symptoms
Delirium, seizures, coma and death
- blood is diluted and moves to ICF, leading to edema, lung congestion and muscle weakness
Water balance in increased by
Water in liquids and floods and products of metabolism
Water balance is decreased by
Loss through kidneys, skin, lungs and feces
Total % of body weight of water in infants
75%
Total body weight % of water in males
60%
Total body weight % of water in females
50%
