Trace Minerals Flashcards
Foods with trace minerals
- grains (iron, zinc, copper, selenium, chromium)
- milk (zinc)
- meat and beans (selenium, iron, zinc, copper)
Factors that increase bioavailability
- Deficiency will increase absorption.
- Cooking (denature protein to free up mineral)
- Vitamin C (with iron); animal protein (with zinc)
Factors that decrease bioavailability
Iron
Chief Function
-Hb and myoglobin
Iron
Deficiency
Most common nutrient deficiency
At risk: women, menstruating women, pregnant women, growing children/adolescents, celiac’s patients
Symptoms: anemia (causes fatigue, faintness, feeling cold, SOB), immunosuppression (Fe needed for immune enzymes), low IQ, pica, glossitis, angular stomatitis, spoon nails
Anemia: RBCs are hypochromic and microcytic;
Determine by looking at ferritin, transferrin, and hemoglobin (in that order). Ferritin test more most specific in catching early iron deficiency (vs. measuring hemoglobin)
Iron
Toxicity
Hemochromatosis=excess iron in fibrotic tissue damage
Bronze diabetes (pigmentation of skin and DM)
Caused by iron overload from ingestion or transfusion, or genetic hyper-absorption
Symptoms: infection, skin pigmentation, organ damage
Zinc
Chief Function
- part of insulin
- gene transcription as zinc fingers
- part of pancreatic digestive enzymes
- stabilizes cell membrane proteins and receptor proteins for vitamins A, D and thyroid hormone
- immune response
- gene expression
- sexual development
- taste and smell senses
-found in seafood
Zinc
Deficiency
Acrodermatitis Enteropathica: recessive metabolic disorder that affects zinc uptake, resulting in dermititis around natural orifices and limbs, loss of hair, and diarrhea
- retardation of growth and sexual development
- loss of smell and taste
- poor appetite
- poor wound healing and impaired immunity
- hair loss
- skin and eye lesions
Copper
Chief Function
- part of Hb
- part of lysyl oxidase needed for skin, hair, and CT
- promotes iron transport as part of ceruloplasmin
- part of enzymes needed for protection against free radicals
Copper
Deficiency
- Menkes Syndrome: poor copper absorption
- Anemia, CT damage, and excessive bleeding
Copper
Toxicity
WILSON DISEASE: copper deposits in brain, kidney, cornea, and liver with low blood copper levels
- low ceruplasmin levels
- Kayser-Fleischer ring around eyes; goes away with treatment
- treat with zinc, which can reduce copper absorption, or copper chelator
Liver damage
Selenium
Chief Function
- part of antioxidant enzyme glutathione peroxidase
- regulates 5’deiodinase, needed for thyroid hormone
- immune function
- food content of selenium dependent on soil content
- Brazil nuts
-absorption is efficient and not regulated
Selenium
Deficiency
Keshan Disease-found in areas with low selenium soil content
-causes enlarged heart and poor cardiac function
Selenium
Toxicity
- nail and hair brittleness
- nervous system disorders
- garlic breath
Iodine
Chief Function
-Thyroid hormone
- iodine content in food is dependent upon iodine content in soil
- saltwater, seafood, seaweed, iodinized salt
Iodine
Deficiency
-Under active thyroid gland which can cause goiter, mental and health retardation, cretinism
Iodine
Toxicity
Goiter
Underactive thyroid gland
Fluoride
Chief Function
- Bone and teeth health by forming hydroxyappetite crystals
- not essential because body processes can occur without it
2 Forms of Iron
- Heme: only from animals; makes up 10% daily Fe intake, but it absorbed well
- Non-heme: all of the iron from plant based foods is non-heme; makes up 90% of daily Fe intake, but is not as well absorbed
Factors that enhance non-heme absorption
- increased body need
- vitamin C (changes oxidation state from +3 to +2 in order to be absorbed)
- animal tissue (MPF factor and heme iron promote absorption of non-heme iron)
- sugar
- acid (changes oxidation state from +3 to +2)
Factors that inhibit non-heme absorption
- binding agents (oxalates, phytates, polyphenols, fiber)
- low gastric acid content, which could be due to PPIs or antacids
- infection (body doesn’t want to absorb iron that foreign organisms could use)
- large amounts of other minerals that could compete for absorption
Ceruloplasmin
- involved in oxidation of iron from +2 to +3 so it can be put in transferrin; especially important for Fe recycling in macrophages (senescent erythrocytes are phagocytosed by macrophage, components broken down into heme and globin, Fe2+ from heme is converted to Fe3+ by ceruloplasmin in order to bind to transferrin)
- major copper containing protein in plasma; transports copper from liver to tissue
Goitrogens
- reduce bioavailability of iodine
- found in raw vegetables, but destroyed in cooking
Chromium
Enhances insulin action
