Chapter 12 - Fat Soluble Vitamins Flashcards
(100 cards)
1
Q
What are vitamins?
A
essential organic compounds needed in small amounts
2
Q
Are vitamins a source of energy?
A
NO
3
Q
Vitamins needed for what?
A
energy metabolism
growth
development
maintenance
4
Q
What are the fat-soluble vitamins?
A
A, D, E, K
5
Q
Fat-soluble vitamins dissolve in what?
A
organic solvents
6
Q
What are the water-soluble vitamins?
A
B-vitamins
Vitamin C
7
Q
What are the sources of fat-soluble vitamins?
A
plant and/or animal depending on the vitamins
8
Q
Fat-soluble vitamins absorbed with what?
A
dietary fats
9
Q
Fat-soluble vitamins rely on what?
A
bile
pancreatic juices
10
Q
% of fat-soluble vitamins absorbed?
A
40-90% under optimal conditions
11
Q
Water-soluble vitamins not dependent on what?
A
dietary fats
12
Q
% of water-soluble vitamins absorbed?
A
90-100%
13
Q
Water-soluble vitamin absorption occurs where?
A
small intestine
14
Q
Fat-soluble vitamins must be efficiently absorbed where?
A
small intestine
15
Q
If absorption is decreased, what must happen?
A
more must be consumed
16
Q
Fat-soluble issues?
A
GI tract disease
Pancreatic disease
17
Q
What may lead to malabsorption of some B-vitamins?
A
alcohol abuse
18
Q
Examples of vitamin absorbency diseases?
A
cystic fibrosis
crohns
19
Q
Fat-soluble vitamins are delivered with what?
A
dietary fats
20
Q
Fat-soluble vitamins are delivered in what?
A
chylomicrons
lipoproteins
21
Q
What remnants contain fat-soluble vitamins?
A
chylomicron
22
Q
What repackages these vitamins to transport to cells in the body?
A
liver
23
Q
If not put into blood transport, what happens to these vitamins?
A
stored in liver or adipose tissue
24
Q
Water-soluble vitamins are delivered where?
A
directly to bloodstream and distributed
25
Fat-soluble vitamins are stored where with the exception of what?
liver and adipose tissue
| Vitamin K
26
Are fat-soluble vitamins readily excreted from the body?
NO
27
Describe the stores of water-soluble vitamins.
limited stores except B-12 and B-6
28
Are water-soluble vitamins readily excreted from the body?
yes
29
How often should water-soluble vitamins be consumed?
daily
30
Retinoids
preformed vitamin A compounds
31
Carotenoids
plants contain pro-vitamins to vitamin A
32
Where are retinoids found?
```
liver
fish
fish oils
fortified milk
eggs
```
33
Where are carotenoids found?
dark-green and yellow-orange veggies and fruit
34
70% of vitamin A in North America comes from what?
animal sources
35
Dietary vitamin A activity is expressed how?
Retinal Activity Equivalents (RAE)
36
Key functions of vitamin A
growth and development
immune function
cell differentiation
vision
37
During growth and development, what does vitamin A lend to?
eyes, limbs, cardiovascular system, nervous system
38
Vitamin A deficiency during pregnancy?
birth defects
| infant mortality
39
How does vitamin A contribute to the immune system?
helps maintain epithelium, which is the barrier that protects the body against entry of pathogens
40
Is vitamin A deficiency common in North America?
no, it is rare
41
Is vitamin A deficiency common in developing countries?
yes
42
Worldwide, vitamin A deficiency is the leading cause of what?
nonaccidental blindness
43
What eye diseases could result from a vitamin A deficiency?
night blindness
Bitot's spots
Keratomalacia
Xerophthalmia
44
How does a lack of vitamin A create night blindness?
retina regenerates rhodopsin more slowly
45
Bitot's spots
gray spots caused by hardened epithelial cells
46
Keratomalacia
softening of the cornea
47
Xerophthalmia
sequence of changes in the eye, resulting in blindness
48
What skin disease could result from a vitamin A deficiency
follicular hyperkeratosis
49
Follicular hyperkeratosis
hardened keratin replaces mucous-forming epithelia
50
Hypervitaminosis A
long-term supplement use at 5 to 10 times RDA for retinoids
51
What is the UL for retinol?
3000 mg/day
52
Is there a UL for carotenoids?
no
53
What are the three kinds of vitamin A toxicity?
acute
chronic
teratogenic
54
Acute vitamin A toxicity
caused by one large does in a day or several large doses over a few days
55
Chronic vitamin A toxicity
symptoms occur with repeated intakes of 10x RDA
56
Teratogenic vitamin A toxicity
can cause spontaneous abortions and birth defects
57
Why is vitamin D the "sunshine vitamin"?
presence of sunlight allows cells to synthesize vitamin D from a cholesterol derivative
58
Why are there strict limitations on the categories of foods that can be fortified with vitamin D?
toxic at high levels
59
What foods contain vitamin D2?
fatty fish
cod liver oil
fortified milk
fortified breakfast cereals
60
Calcitrol
helps maintain blood levels of calcium and phosphorous, which maintains bone health
61
When calcium is low, what does vitamin D do?
increases intestinal absorption of calcium and phosphorous
62
When blood calcium levels are low, what does vitamin D do to bones?
releases calcium and phosphorous from bone to restore blood levels
63
When vitamin D is deficient, what happens to calcium?
dietary calcium cannot be absorbed efficiently, which can cause problems with bone mineralization and structure
64
What is the vitamin D deficiency found in children?
Rickets
65
What is the vitamin D deficiency found in adults?
Osteomalacia
66
Oversupplementation of vitamin D can cause what?
- high blood and urine calcium concentrations
- depositing of calcium in blood vessels and kidneys
- cardiovascular damage and possibly death
67
What happens during chemical reduction?
gain of electrons
68
What happens during chemical oxidation?
loss of electrons
69
What part of a REDOX reaction is dangerous?
oxidation
70
What is a free radical?
substance that causes oxidation to happen
71
ROS
reactive oxygen species
72
What do ROS's do?
attack and snatch energy from other cells to satisfy themselves
73
Why is the formation of free radicals dangerous?
causes chain effect of cellular damage
| once one is oxidized because of a free radical, it'll go in search of its own electron
74
What natural processes in the body form free radicals?
metabolism
| inflammation
75
What causes exaggerated formation of free radicals?
UV light exposure
ionizing radiation
smoking
air pollution
76
What do antioxidant vitamins do?
donate electrons to free radicals
77
What must happen to antioxidants to be used again?
must be "recharged"
78
Vitamin E is known as what?
amphipathic
79
Amphipathic
hydrophilic and hydrophobic
80
Active form of vitamin E
alpha-tocopherol
81
What is the activity level of other forms of vitamin E?
low
82
Where is vitamin E stored in the body?
adipose tissue
83
Absorption of vitamin E depends on what?
normal fat absorption
84
Once absorbed, what happens to vitamin E?
incorporated into chylomicrons
85
Good sources of vitamin E include?
anything plant based and oily
86
Vitamin E is highly susceptible to what
destruction by oxygen, metals, light, and heat
87
Is vitamin E an antioxidant?
yes
88
What is vitamin E "recharged" by?
vitamin C
89
Vitamin E can only attach to a free radical once unless?
free radical is removed by vitamin c
90
Is toxicity and deficiency of vitamin E common?
no, least toxic fat soluble vitamin
91
Two types of vitamin K
phylloquinone
| menaquinones
92
Phylloquinone
from plants
| most biologically active
93
Menaquinone
fish oils and meats
| synthesized by bacteria in colon
94
Function of vitamin K
synthesis of blood clotting factors
| preprothrombin ----- prothrombin
95
% of vitamin K from gut flora?
10ish
96
Location of absorption for vitamin K?
large intestine
97
Food sources of vitamin K?
```
green leafies
broccoli
peas
green beans
vegetable oils
```
98
Vitamin K deficiency can cause?
uncontrolled blood loss
99
What can cause a secondary deficiency of vitamin K?
antibiotics
100
Who receives a vitamin K supplement and why?
newborns
| gut is sterile
