Fat soluble vitamins Flashcards
Fat-soluble vitamins are more difficult to ______ _______ (compared to water-soluble vitamins)
eliminate excess
Fat soluble vitamins require _____ and _______ for absorption
bile, chylomicrons
The body stores extra (excess fat-soluble vitamins) in the _____ and ________
overtime, what can happen?
liver and adipose tissue
overtime they can accumulate and cause toxicity
Vitamin A
Classifying forms of Vitamin A
In food, what types of vitamin A are there?
Retinal esters (in animal foods) known as retinoids
Beta-carotene (in plant food). Known as Pro-vitamin A. Also known as Carotenoids. Give colour to foods like carrots. Very high in Vitamin A, why it has that orange colour.
IN the body, what types of vitamin A are there
Retinol
Retinal
Retinoin acid
Retinoids get converted to what in the body?
Retinol
Beta-carotene gets converted to what in the body?
Retinal
What types of vitamin A can be intraconverted from one to the other?
Retinol and Retinal
What gets converted to retinoid acid?
Retinal
When converting retinol to retinal, are they reversible?
Yes, there is a double arrow
retinal to retinoinc acid, are they reversible?
no, they are irreversible. Only one arrow.
What is the function on retinol?
Supports reproduction
circulates in the blood
What is retinal responsible for?
participates in vision
retinoid acid is responsible for what?
regulates growth
Retina (light-sensitive area in ea. eye) contains ____ and______
the rods and cones
Rods enable adaptation to see in poorly ____ environments
lit
Cones responsible for______ ______ and function in well-lit environments
colour vision
what is needed in addition to retinal, for vision?
retinol
Night blindness
some retinal that splits away from rod cells is destroyed. To replace what does the body do?
ro replace the rods remove some retinol from the bloodstream and convert it to retinal
If retinol is unavailable, then what occurs?
night blindness (inability to see in dim light)
Vitamin A is stable when _____ but may be destroyed by exposure to _____ and ______
heated, light and oxygen
Dietary sources of Vitamin A
Animal foods (liver, butter, fish liver oil, eggs)
Toxicity of vitamin A
Acute toxicity:
Chronic toxicity:
Acute toxicity: nausea, vomiting
Chronic toxicity: weight loss, muscle/joint pain
DRI UL 18+ years:
3000 ug/day
Vitamin A is toxic at _________ _____ ______; typically from _______
extremely high doses, supplements
Deficiency in Vitamin A
Threat to health and sight. Vitamin A is directly correlated with the immune system efficiency.
Why are children more susceptible than adults?
poor appetite
Vitamin D (Sunshine Vitamin)
Vitamin D3 is produced in the ______
skin
What do you need to be able to obtain vitamin D from the sun
cholestrol
Vitamin D2 and D3 is absorbed from ______
diet
D2:
D3:
mushrooms, fortified food, dietary supplements
fatty fish, cod liver oil, egg yolk, butter, dietary supplements
what organs create the active form of Vitamin D
liver and the kidneys
When low blood calcium level is present, what happens?
Increases PTH production which creates activation of vitamin D3, the increased synthesis of 1,25 (OH)2 vitamin D3 in kidney. Increase calcium absorption in small intestine
Functions of Vitamin D
regulating _________ and ________ function
neuromuscular and immune function
People living at high altitudes are not as close to the sun so what happens?
they get less vitamin D
Dietary sources of Vitamin D
Fish liver oils and fatty fish
Those south of ____ patrolled and who are outdoors btw 10am - 3pm (when sunlight is more intense) often obtain ______ sun exposure to synthesize _______ _________ during most of the year
33rd, enough, Vitamin D
Toxicity of Vitamin D
DRI UL 19 years:
100ug or 4000 IU/day
Toxicity of Vitamin D does not occur from sunlight or dietary sources, can occur from ________
supplementation
Toxicity can cause high blood ______ (_________)
This can cause ______, _____, _______, _______
Calcium (hyperglycaemia)
nausea, vomiting, weakness, frequent urination
Deficiency in Vitamin A
T or F
Many North Americans do not consume enough Vitamin D
T
Deficiency:
Rickets
T or F
Found mostly in children with dark skin, minimal sunlight exposure, little to no Vitamin D, breastfed
T
Deficiency:
Osteomalacia
Osteomalacia:
soft bones, bend and break easily, especially hips, spine
There is also Vitamin D deficiency with _____
age
T or F
Age reduces skin’s ability to make 7-dehydrochlesterol–> less fortified milk, less sun, can result in secondary hyperparathyroidism (accelerating osteoporosis)
T
Age causes a decrease in blood ______ -> increased _____ -> bone reabsorption
Calcium, PTH
Vitamin E (antioxidant)
There are many forms of Vitamin E, what is the only form found in humans
alpha-tocopherol
Unlike A & D, E is not primarily stored in liver, it is primarily (90%) stored in ______ _____
body fat
Oxidative stress occur because of why?
imbalance between pro-oxidant systems and anti-oxidant system
What are the two ways our body forms reactive oxygen species?
What do these reactive oxygen species cause?
Our body naturally forms reactive oxygen species through the ETC
he other way that our body forms reactive oxygen species is through being exposed to radiation.
ex going on a plane
oxidative stress
How does vitamin E help neutralize reactive oxygen species?
Vitamin E protects vulnerable PUFAs in cell membranes, in blood, and elsewhere by ________ free radicals
scavenging
Vitamin E gives what to the PUFA to neutralize it, so its no longer acting as a reactive oxygen species?
gives an electron and to the PUFA
Explain the 3 steps of how this happens?
- a cell needs a healthy cell membrane to function
- free radicals can damage polyunstaurated fatty acids in cell membranes. Such damage an weaken the membrane
- Vitamin E donates a stabilizing particle to the free radical so it is no longer destructive
After Vitamin E neutralizes the free radical from donating an electron, ______ ___ gives VITAMIN E an electron
VITAMIN C
Vitamine E is destroyed by _____, ____, _____
oxygen, light, heat
Dietary sources of Vitamin E
sunflower seeds, almonds, almond milk, peanuts, plant oils
Toxicity
DRI UL: ______ any form supplemental sources
Excess can cause
1000mg/day
blood thinning, and can lead to fatal bleeding
Deficiency in Vitamin E
nerve and muscle damage, loss of neuromuscular control, blindness
Can also reduce functioning of immune system and cause form of anemia in preterm infants
Vitamin K
“koagulation”
Function: Essential for ______ ________ (coagulation)
without it you would ______ ______
vlood clotting
bleed to death from a single cut
3 types of vitamin K
K1:
K2:
K3:
Phylloquione
Menaquinones
Menadione
Phylloquione (K1):
Menaquinones (K2):
Menadione (K3):
plant sources
animal sources and synthesized by our intestinal bacteria
synthetic form (supplement form)
Functions of K1:
What protein traps blood cells forming a mesh?
Blood clotting
Fibrin
Functions of K2:
regulates the body _____
Bone health
calcium
Unlike A, D, E, body uses K ______ so _______ supply is necessary
rapidly, constant
Dietary Sources of Vitamin K
Major sources of K1:
Major sources of K2:
green leafy vegetables
egg yolks, butter, certain cheeses, liver, beef
Deficiency in K1:
In adults, vitamin K deficiency is rare; usually occurs in people with ____ _________problems (e.g., CF)
Bruising, hemorrhage
fat malabsorption
Deficiency in K2:
can cause increased blood vessel calcification
Increased risk of bone fracture
Practice: Matching
What vitamin is required for the formation of collagen and the absorption of iron
vitamin C
Involved in the production of energy from food and muscle contraction
Vitamin B1 (thiamine)
Require by niacin and vitamin B6
Riboflavin (B2)
Key in the production of red blood cells and folate metabolism
Vitamin B12 (Cobalamin)
Essential for proper functioning of the nervous and immune system
Vitamin B6 (pyridoxine)
Necessary for normal growth and development
Vitamin B9 (folate)
Essential for blood clotting and bone health
Vitamin K
Supports the immune system and acts as an antioxidant
Vitamin E
Regulates calcium and phosphorus absorption for bone health
VItamin D
Helps maintain health skin and vision
Vitamin A
Levels rely on iron, riboflavin, or Vitamin B6 status
Vitamin B3 (niacin)
