Fat Soluble Vitamins Flashcards
What are 2 types of water vitamins
- Non B complex- only Vit C
- B complex
Water Soluble vitamin
not stored (only b12 is)
HIghly absorbed
excreted in ua
low tox level
Fat Soluble Vitamins
Accumulate in “stores”
Require dietary fat absorption
+/- blood transport system
Potential toxicity with excess intake
Vitamin A Function
Photochemical for vision
retinal signaling
Maintenance of conjunctiva and cornea
xerophthalmia (corneal dryness)–> Bitot’s Spots, night blindness –> total blindness
Vitamin A deficiency
Food sources for Vitamin A
Animal sources
Precursor beta carotene- dark vegetable
Vitamin A - Deficiency Immune Impairment
Dysregulation
Treatment of Deficiency decreases all cause child mortality 23-34% in developing world
Vit A treatment with measles reduces morbidity and mortality including in US when retinol level is low
Vitamin A deficiency eyes
xerophthalmia (corneal dryness)–> Bitot’s Spots, night blindness –> total blindness
Vit A - Toxicity
not seen with precursor
s/s:
NV, ↑ ICP, HA
Bone pain
- Birth defects
- liver damage hepatitis–> fibrosis–> failure–> Death
Vit A – Risk of Deficiency
Low Vit A intake
Diet poor in colored veggies, meat/dairy
Protein Energy Malnutrition
Very Low fat intake (
Serum Retinol level
Remains normal until liver stores exhausted
Decreased with inflammation
Negative Acute Phase Reactant
Vit A – Laboratory Testing
Vit A – Laboratory Testing
Serum Retinol level
Remains normal until liver stores exhausted
Decreased with inflammation
Negative Acute Phase Reactant
Hormone- Plasma membrane and nuclear receptors in a range of tissues
Vit D
Also Ca regulation and immune system
Vitamin D sources
Conversion in skin
Diet (fish, fat, egg)
UVB light–> Dehydrocholesterol–> Cholecalciferol D3 in skin
Conversion in skin Vit D
Vit D - Metabolism
Absorption – chylomicrons
Requires fat absorption
D2 or D3 +OH in ______
25 OH Vit D –level reflects body stores
liver
Deficiency 25OH Vit D
25 OH Vit D hydroxylated in _____ to active form 1,25 OH Vit D (Calcitriol)
kidney
If kidneys dont work, may have vit d def
Deficiency 25 OH Vit D
Childhood rickets -
Vit D – Risk for Deficiency
Low Sun exposure Dark skin Low dietary intake Fat Malabsorption Breastfed Infant Obesity -- Fat sequestration, sedentary Liver or Renal Disease (X-OH)-- Need Calcitriol Rx supplementation
How much to use vit d
Breastfed Infants - 400IU D3 per day by 2 months
600 IU/d for children
Adults- variable
Sun exposure and Vit D
5-15 min of arm and leg in sun will get correct amount
derms recommend do supplement instead
Vit D - Toxicity
Hypercalcemia==> Vomiting, seizures, nephrocalcinosis, vascular and soft tissue calcinosis
Sarcoidosis
Function: antioxidant, scavenges free radicals, stabilizes cell membranes
Vitamin E – Function
Vitamin E sources
polyunsat fat veggie oil
corn
nuts
Vitamin E – Function
antioxidant, scavenges free radicals, stabilizes cell membranes
Neurologic Degeneration IRREVERSIBLE Loss of reflexes (DTRs) Loss of coordination Loss of vibration and position sense Spinocerebellar ataxia Neuropathy Ophthalmoplegia
Vit E – Deficiency
Vit E – Deficiency
Neurologic Degeneration IRREVERSIBLE: Loss of reflexes (DTRs) Loss of coordination Loss of vibration and position sense Spinocerebellar ataxia Neuropathy Ophthalmoplegia
hemolytic anemia
Vit E – Toxicity
Relatively Low
Coagulopathy
Very large doses inhibit Vit K dependent clotting factors
Vit K – Function
Function – carboxylation of clotting factor proteins (II prothrombin, VII, IX, X)
Vit K Source
leafy green broccoli fruit seeds beef liver
Vitamin K - Deficiency
prolonged coagulation time
Hemorrhagic disease of the newborn
Purpura, GI bleeds, CNS bleeds
