Micronutrients Flashcards
Iron
Trace mineral, part of hemoglobin. Food iron = ferric, body converts to ferrous, stores as ferritin. Aids in oxygen transport. Animal proteins are heme source, non-heme sources are cereals and veg but these are poorly absorbed. Abs. Aided by gastric juice and vitamin C. Calcium helps if oxalates are present. Absorption inhibited by eggs, tea, milk, cheese.
NEEDS: 8 mg male, 18 mg female.
Deficiency s/s: pale tongue, fatigue, anemia, spoon nails. Pale conjunctiva.
Phosphorous
Second most abundant mineral
Phospholipids transport fat through lymph and blood. Strengthens bones and teeth.
Found in meat, milk, poultry, eggs, fish, cheese.
Needs: 700mg
Deficiency is rare.
Magnesium
Part of chlorophyll. 50% in bone, 50% in cells. Aids in protein and fatty synthesis, stabilizes structure of ATP, high protein, calcium, and vitamin D all increase need. Found in most foods, milk, bread.
Needs: males 420 mg, females 320 mg. Deficiency is rare but causes tremors.
Zinc
Trace mineral, excess leads to copper or iron deficiency. Increases taste acuity, enhances insulin action, stabilizes DNA, RNA,, cell division. Found in meat, liver, eggs, fish, phytates and copper decrease absorption. Males 11 mg, females 8mg. Deficiency: reduced immune function, alopecia, poor wound healing, hypogeusia.
Iodine
Trace mineral, part of thyroxine. Found in seafoods and iodized salt. Needs 150 micrograms, deficiency causes goiter.
Fluoride
Trace mineral that strengthens teeth and bone. Found in soil and water. Needs: males 4mg females 3 mg. deficiency causes dental caries.
Copper
Trace mineral attached to protein ceruloplasmin. Role in Hemoglobin synthesis, aids iron absorption. Sources- liver, kidney, shellfish. Needs- 900 micrograms
Deficiency is rare: microcytic anemia, neutropenia, Wilson’s dz: low serum copper, genetic absence of liver enzyme.
Selenium
Cooperates with Vitamin E, trace mineral. Antioxidant with role in tissue respiration. Found in soil, grains, meat, fish, poultry, dairy.
Needs: males 55 micrograms, females 45 micrograms.
Def: myalgia, cardiac myopathy.
Manganese
Trace mineral, role in central nervous system. Found in whole grains, legumes, nuts. Needs: 1.8-2.3 micrograms. Deficiency is unlikely.
Chromium
Absorption enhanced by vitamin c, niacin. Ultra trace mineral. Aids in insulin action and glucose metabolism. Found in yeast, oysters, potatoes, liver.
NEEDS- 25-35 micrograms. Deficiency leads to insulin resistance.
Cobalt
Exists with B12, stored in liver. Role in maturation of red blood cells.
Deficiency is related to b12 deficiency.
Sulfur
Part of amino acids: cysteine, cystine, methionine
Component of organic molecules
Found in meat, fish, eggs, poultry, animal proteins.
Needs- 425-550 mg AI
Choline
Component of lecithin, transports lipids as acetyl choline.
Found in the fat in eggs, milk, liver, soybeans.
Chromium and zinc
Important for glucose metabolism
Increase energy expenditure
Increases need for thiamin, niacin, riboflavin, pantothenic acid.
Vitamin A
Stored in liver. Carotene is precursor, and provitamin (conversion in intestinal mucosal cells). Toxic @ 10,000 IU.
Functions in skin and vision.
Found in yellow and orange f/v, dark leafys, fish, liver, fort. Skim milk.
Needs: males 900 micrograms RE, females 700 micro RE
Def: night blindness (nyctalopia- dark adaptation test, reversible)
Xerophthalmia- corneal damage, not reversible
Bitot’s spots- on conjunctiva
Dry scaly skin (hyperkeratosis)
Vitamin D
7 dehydrochokesterol->
D3 cholecalciferol ->
D2 ergocalciferol
Cholesterol is precursor. UV light.
Aids in calcium and phosphorous metabolism.
Sources- sun, egg yolk, fortified milk
Needs- 5-15 micrograms
Def- rickets, osteomalacia (adult rickets)
Vitamin E
Tocopherol, one of least toxic. UL 1,000 mgs
Antioxidant, resists hemolysis of red blood cells.
Sources- veg oils, whole grains, green veg, almonds.
Needs- 15 mg
Def- hemolytic anemia
Vitamin K
Synth by bacteria in colon, no toxicity. Forms prothrombin in liver aiding in blood clotting. Given pre-surgery. Role in calcium metabolism. Found in green leafys.
Needs- males 120 micrograms, females 90 micrograms
Def: hemorrhage, affected by: mineral oil, abx, anticoagulants.
B1- thiamin
Water sol. Lost as temperature or pH rises. Heat stable in acid. Role in oxidation of cho. Increase cho increase thiamin. Role in metabolism of pyruvate. Found in grains, wheat germ, pork, liver.
Needs- males 1.2 mg, females 1.1 mg.
Def: beriberi, muscle weakness, foot drop, memory loss, tachycardia
Decrease erythrocyte transketolase, increase in plasma pyruvate.
Vitamin B2 (riboflavin)
Lost in uv light. Role in energy release from protein and red cell production.
Source: liver, kidney, meat, milk.
Needs: males 1.3 mg, females 1.1 mg.
def- growth failure, cheilosis (cracked lips), angular stomatitis, magenta tongue.
Niacin
Precursor- tryptophan. Essential in all cells for energy production and metabolism. Role in metabolism cho/pro/fat.
Found in protein, peanuts, ready-to-eat cereals, chicken, rice, yeast, milk
Needs: males 16 NE, females 14 NE
Def: pellagra, dermatitis, diarrhea, dementia (four d’s)
Beefy bright red tongue, symmetrical pigmented rash in sunlight
Folate
Water sol, PABA is precursor. Role in DNA synthesis, forms of RBC in bone marrow, prevents neural tube defects.
Found in fort. Dry cereal, liver, kidney, green leafys, veg, Citrus, lentils, beans.
400 micrograms
Megaloblastic, macrocytic anemia, diarrhea, fatigue.
B6- pyridoxine
INH- isoniazid is B6 tb drug antagonist.
Role coenzyme in amino acid metabolism: Deamination and transamination. Increasing protein requires increased pyridoxine.
Sources- meat, wheat, corn, yeast, pork, liver, cereals.
Needs- male 1.2-1.7 mg
Female 1.3-1.5 mg
Deficiency: seizures, anemia, dermatitis, glossitis, peripheral neuropathy.
B12 cyanicobalimin
Contains cobalt, bound by intrinsic factor in gastric juice. Coenzyme in protein synthesis. Forms red blood cell.
Sources: liver, meat, milk, kidney, eggs, fish, cheese
Needs- 2.4micrograms
Deficiency: macrocytic, megalovlastic anemia. Pernicious anemia following grastrecromy or illegal resection d/t lack of intrinsic factor.
Pantothenic acid
Coenzyme a- energy synth of fatty acids. Found in animal foods, grains, legumes.
Needs: AI 5 mg
Rare deficiency: paresthesia in feet
Vitamin C, ascorbic acid
Most easily destroyed, structure like glucose. Antioxidant- needs acidic pH. Destroyed by heat, alkaline pH, oxidation.
Changes proline into hydroxyproline into collagen which strengthens intercellular substances. Wound healing, aids in absorption of iron.
Found in citrus, potatoes, papaya, dark green, yellow veg.
Needs: 75-90mg
Def: scurvy, poor wound healing, bleeding gums, petechiae
Biotin
Synth by intestinal bacteria, inactivated by avidin ( protein in raw egg white)
Coenzyme in fatty acid synthesis, converts pyruvate to oaa in gluconeogenesis.
Liver, kidney, egg yolk, yeast.
AI 30 micrograms.
Def:
Muscle pain, dermatitis, glossitis
Myo-inositol
In plants as phytic acid, related to sugar, contains phosphorous like vitamin like factor.
Binds calcium, zinc, iron, membrane structure.
Found on outer husks of cereal grains and leafy greens.
Calcium
Most abundant mineral.
Regulated by parathyroid hormone. Vitamin d, acid, and lactose aid in absorption. Calcitonin: lowers serum calcium by inhibiting bone resorption.
Role in blood clotting, cardiac function, nerve transmission, smooth muscle contraction.
Sources: dairy products, leafy veg, legumes.
Needs: 1000- 1200 mg
Def- hypocalcemia leads to tetany
