nutrition exam 4 fat soluble

what are the fat soluble vitamins

A, D, E and K

absorption occurs in

small intestine

mostly stored in

liver, some in adipose

____ stable than H2O vitamins

more

large quantities can be

toxic

retinoids are _____ forms of vitamin A

active

vitamin A primary source

animal source and a few plants

• dietary products, liver, organ meats, fatty fish

Vitamin A inactive

caritenoids

beta-carotene

nonprovitamin A carteniods

since carotenoids are not active they are not

toxic

beta-carotene

orange/red/yellow pigments

major source plants

nonprovitamin A carotenoids

cannot be converted to vitamin A (not true vitamin in this form)

vitamin A and carotenoids major function

vision

growth

immune function

cancer prevention

bone strength

vitamin A and carotenoids deficiency

night blindness

xerophthalmia (“scaling“ of cornea)

hyperkeratosis (too much growth of keratin)

hypervitaminosis A

chromic over supplementation

blurred vision, liver damage, decreased bone strength

birth defects- medication, Accutane(oral), Retin-A(topical)… missing ears, mental defects and other reported

carotendermia

yellowing of skin

(vitamin a toxicity)

osteoclasts

bones cells that tear down

osteoblasts

bone cells that build up

Vitamin D is the

“Sunshine Vitamin“

vitamin D2

ergocalciferol

• plant source: mushrooms

vitamin D3

cholecalciferol

• animal source: fatty liver, egg yolks, butter, whole milk dairy products

vitamin D1

found not to be pure vit D compound

vitamin D is stable during

food preparation, processing and storage

vitamin D is produced by

the body in the skin (UV light)

7-dehydrocholesterol is converted to

precalciferol

Vitamin D3 influence factors

environment (sunny or foggy), skin color (melanin, less has more D formed), age (less formed in elderly)

precalciferol is converted to

cholecalciferol (D3)

vitamin D function

calcium homeostasis

cell differentiation

vitamin D deficiency

bone demineralization

chronic degenerative disease

low vitamin D

rickets

Hypercalcemia

excess blood calcium; bone loss weakened bones, kidney stones

Hypercaluria

excess calcium in urine; can cause renal insufficiency, deposits in soft tissue

vitamin E most active compound

α-tocopherol

vitamin E source

Vegetable oils, nuts, seeds, dk green vegetables

Vitamin E storage

adipose tissue

vitamin E functions

antioxidants

cancer prevention

prevention of cataracts

cardiovascular health

Vitamin E supplements are

not recommended

could possibly increase risk of prostrate cancer

Vitamin E deficiency

hemolytic anemia (rupturing of RBC)

neuromuscular problems

K1

phylloquinone

• plant foods

K2

menaquinone

• bacteria in the large intestine

K3

menadione

• Produced commercially (synthetic); not for humans, for poultry, pig feed, pet foods

vitamin K sources

Green vegetables, most from gut bacteria

vitamin K destruction

light or heat

vitamin K function

blood coagulation

bone formation

vitamin K deficency

vitamin k deficiency bleeding (VKDB)