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Flashcards in Vitamins and Nutrition Deck (35)
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  • Cofactors in enzyme reactions
  • Fat soluble or Water-soluble


Fat Soluble Vitamins, Storage

Stored in Liver or Adipose tissue and can accumulate to toxic levels

A, D, E, K


Water Soluble Vitamins, Excretion

Easily lost in urine, generally do not accumulate

C and B Vitamins


Retinol (A)

Deficiency causes drying, degeneration, risk of eye infections, night blindness

High levels can cause Liver disease

Carried in plasma by retinol binding protein and transthyretin then converted to Retinal in the eyes


Vit D, Interactions with PTH and Ca

Proper skeletal formation (rickets, osteomalacia, osteoporosis), mineral/hemostasis, sun catalyzes formation

  1. Interacts with PTH and Ca which regulates production in kidney, measured in parathyroid and cardiac disease
  2. PTH stimulates renal release and activation of VitD, controlled by Ca levels and high VitD levels
  3. Active hormone produced by kidney metabolism and stimulates reabsorption of Ca and P, overload can cause deposits in renal system
  4. Circulates in plasma bound to VitD binding Alpha Globulin Protein
  5. Secondary Controls of Bone Minerals (Calcitonin, Glucocorticoids, Estrogens), stimulates intestinal absorption of Ca and PO4


Vitamin E

Antioxidant, defense against disease/aging, protects RBC membrane, deficiency causes hemolytic disease in premature neonates


Vitamin K

Needed for Thrombin formation, lack of causes hemorrhage

Synthesized from dietary precursors by bacteria in Intestines or in Liver

Antibiotics can kill off the bacteria, Liver damage inhibits synthesis


Vitamin K and Warfarin

Lipid soluble, oral administration

Inhibits VitK posttranslational modification and increases clotting time, crosses placenta and cannot be given during pregnancy

Effectiveness measured via prothrombin time


Vitamin Sources

VitD related, PTH, VitD in dairy, Calcitonin in Salmon, Ca can be given via many methods


Testing for VitD

For calcium homeostasis via immunoassay


B1 (Thiamine)

Deficiency causes beriberi (severe peripheral nerve damage)

Coenzyme in carbohydrate/amino acid metabolism

Functional activity measured by RBC transketolase activity


B2 (Riboflavin)

Deficiency causes photophobia

Cofactor for FAD needed for oxidation reactions

Body contains stores for 5 months of deficiency, deficiency indicated if glutathione reductase activity is greater then 40%


B6 (Pyridoxine)

Deficiency causes Facial Seborrhea and hyperhomocystinemia


Niacin (nicotinamide)

Deficiency causes Pellagra

Needed for NAD/NADH cofactors

Dosing lowers cholesterol levels


Folic Acid/B12

Deficiency causes megaloblastic anemia

Cofactor for essential biochemical reactions (Methyl transfers in DNA synthesis, and Isomerization of L-methylmalonyl CoA with B12 deficeincy), extrinsic factor for cyanobalamin

Folate Supplementation in megaloblastic anemia, corrects anemia, prevents neural tube defects, prevents cardiovascular accidents with reduced homocysteine levels


Megaloblastic Anemia

Large nucleated red cells with reduced RBC production, loss of absorption of B12 in GI (distal ileum)


Pernicious Anemia

Lack of intrinsic factor which is required for B12 absorption


Schilling Test

Patient is given radioactive B12 and 24hr urine is collected and measured for radioactivity


Vitamin C

Deficiency causes scurvy, hemorrhagic disorders, anemia

Needed in collagen formation and mineral absorption

Measured via HPLC


Clotting Cascade and Vit K

Anticoagulants, for treatment of patients at risk of vascular occlusions or increase clotting in clotting deficiencies

Drugs Facilitating clotting, replacement factors, VitK, Antiplasmin


Essential Fatty Acids

Polyunsaturated fatty acids: 

  1. Omega 6
  2. Omega 3

Testing Methods: GC, HPLC


Omega 6

Platelet adhesion


Omega 3

Form prostaglandins, leukotrienes, reduce inflamm., support immune system


Crohns Disease

Fatty acid deficiency


Nutritional Assessment

  • Metabolic evaluation
  • Recent weight changes
  • Creatinine/height index
  • Immune testing
  • Protein Markers


Recent weight changes in Nutritional Assessment

Unintentional weight loss of 10% or more


Creatinine/height index in Nutritional Assessment

Measures lean body muscle mass


Immune testing in Nutritional Assessment

Can be insensitive to determining cause


Protein Markers in Nutritional Assessment

Prealbumin, albumin


Decreases in Nitrogen Balance

During stress, burns, trauma