Chapter 7 Vitamins Flashcards
What is the definition of a vitamin?
noncaloric essential nutrient
Do vitamins need to be taken in by the diet?
yes
What are the functions of vitamins?
metabolism
Which vitamins are fat soluble?
A, D, E, K
Which vitamins are water soluble?
Bs and C
What are the main functions of Vitamin A?
vision
growth
tissue strength
immunity
What are the two sources of Vitamin A?
foods: preformed (animals), beta-carotine (plants)
liver: stored
What is seen with a Vitamin A deficiency?
xerosis: itching, burning, red, inflamed eyelids
xerophthalmia: blindness
What is see with too much vitamin A?
hypervitaminosis A: bone pain, dry skin, hair loss, fatigue, anorexia, liver damage
What are animal food sources of vitamin A?
fish liver oils, egg yolkds, butter, cream, milk fat
what are plant food sources of vitamin A?
dark green leafy vegetables, dark orange vegetable sand fruits
What is vitamin D known as ?
calciferol
What is vitamind D3 called?
cholecalciferol
what is vitamin D2 called
ergocalciferol
How is cholecalciferol (D3) produced?
humans exposure to sunlight
What hormone is cholecalciferol converted to in the kidney?
calcitriol
what does calcitriol do?
increases the abosorption of calcium and phosphorus from intestines
prevents calcium being eliminated from kidney
increases osteoclast activity
What does vitamin D (calciferol) deficiency cause?
rickets/softening of bones (bowlegs)
What are symptoms of hypervitaminosis D?
fragile bones, kidney stones, calcification of soft tissue
what are good food sources of vitamin D?
fatty fish
fortified milk
What is the name for vitamin E?
tocopherol
What is the vitamin E deficiency in premature babies?
hemolytic anemia
What can a vitamin E deficiency cause in adults?
affect myelin in individuals who cannot absorb or metabolize fat
what are food sources of vitamin E
vetable oils
nuts
seeds
What is the dietary form of vitamin K from plants?
phylloquinone
what is the form of vitamin K produced by intestinal bacteria?
menaquinone
what is vitamin K important for?
bone clotting
bone development
do we have vitamin K dietary requirements?
no
where do we get most of our vitamin K?
bacteria in our body
what are food sources of vitamin K
green leafy vegetables
