Transcript Fat soluble vitamins

FAT SOLUBLE VITAMINS
Vitamins A,D,E,K
• Functions
• Effects of deficiency
• Sources
• Properties
• RDA
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© PDST Home Economics
VITAMINS
• “VITAMIN” means “vital for life”
* Nutrients required
in very small amounts
- mg or µg
• VITAMINS are *Micronutrients
which are necessary for everyday healthy
functioning of the body
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VITAMINS Two main categories
Water soluble
Fat Soluble
B
C
A
D
E
K
Water soluble
• Cannot be stored in body
- regular supply needed
Fat Soluble
• Can be stored in body regular supply not needed
• Excess is excreted in
• Can accumulate to toxic
urine - no danger of toxic
levels if large amounts
levels
ingested
• Unstable to heat and
light, leach into cooking
liquids
• Fairly stable at normal
cooking temperatures
Vitamin A - Retinol and BetaCarotene
Retinol
Beta-Carotene
Named because of its
concern with retina of
eye
Only found in animal
foods
Present with chlorophyll in
plants, converted to
Vitamin A in gut wall
Vitamin A –
Retinol and Beta-Carotene
Functions
Effects of deficiency
• Regulates growth
• Retarded growth,
malformed bones
• Promotes healthy skin
• Dry mucous membranes
• Maintenance of
healthy epithelial
• Xeropthalmia - dry eye
tissues
membrane
The moisturising
vitamin!
• Necessary for
• Night blindness
production of
• Susceptibility to
Rhodopsin - pigment
infection
in retina, helps eye
adapt to dim light
Go for Color!
• Vitamin A is what your body needs
It gives you healthy bones and good strong teeth
Beautiful hair that shines bright in the daylight
Healthy eyes so you can see at night............
• ©1999 Dole Food Company, Inc
Now carotenes are real big news
They give fruits and veggies colourful hues
Eat yellow, orange, red and deep green
'Cause they're rich and loaded if you know what I mean
Vitamin A - Retinol and BetaCarotene
Carotene
Sources
Retinol - Cod liver oil,
liver, dairy products,
herring, egg yolk
Beta-Carotene
Dark green leafy
vegetables, broccoli,
carrots, deep orange
fruits and vegetables
Go for Color!
Think
Yellow, Orange,
Red, Deep Green
Now carotenes are real big news
They give fruits and veggies colourful hues....
Vitamin A - Retinol and BetaCarotene
Properties
• Yellow fat soluble alcohol
• Insoluble in water
• Can be destroyed by
oxygen, light and air
• Some reduction in
dehydration
• Powerful antioxidant
RDA
600 µg per
day
90% of
Vitamin A in
the body is
stored in the
liver
Vitamin D - Calciferols
Cholecalciferol
The sunshine
Vitamin!
The sun activates Provitamin
7 dehydro cholesterol
Ergocalciferol
Formed by action of ultra
violet light on fungi and
yeasts
present in fat under skin
Provitamin 7 dehydro cholesterol
Cholecalciferol
Manufactured synthetically
for use as vitamin
supplement
Vitamin D -Calciferols
Functions
• Absorption and laying
down of calcium and
phosphorous in bones
and teeth
• Regulates calcium
balance between bones
and blood
• Prevents rickets
Effects of deficiency
• *Rickets in children and
*osteomalacia in adults
* Conditions where bones
are soft and cannot take
weight of the body
• **Osteoporosis
**Bones become light, less
dense and prone to
fractures
• Dental caries
Vitamin D -Calciferols
Sources
Sunlight conversion
Fish liver oils
Dairy products
Oily fish
Margarine
Vitamin D -Calciferols
Probably
the most
stable of
the vitamins
Properties
• Fat soluble
• Insoluble in water
• Stable to heat, acids,
alkalis, oxygen
• Unaffected by cooking or
preservation
RDA
7 -10µg per
day
Vitamin E -Tocopherols
Anti coagulants
and anti oxidants
Functions
• Powerful antioxidant
• May reduce risk of
heart disease, stroke,
cancer
• Improves absorption
of vitamin A
Effects of deficiency
• Deficiency is rare
• Linked to conditions
associated with
malabsorption of fat
• Nerve damage, loss of
balance, lowered immune
system
Vitamin E -Tocopherols
Sources
Wheatgerm
Oatmeal
Oils and animal fats
Leafy greens
Eggs
Vitamin E -Tocopherols
Properties
• Fat soluble
• Insoluble in water
• Stable to heat, unaffected
by cooking or preservation
• Acts as antioxidant, delays
rancidity and oxidation
• Damaged by alkalis and UV
light
RDA
Based on
polyunsaturated
fatty acid
intake
Sometimes called
“Coagulation” vitamin
Vitamin K - Napthoquinones
Functions
Effects of deficiency
• Constituent of
prothrombin which is
necessary in blood
clotting
• Abnormal clotting,
bleeding.
• Deficiency is rare
Vitamin K - Napthoquinones
Sources
Dark green vegetables
Liver
Lean meat
Eggs
Manufactured by bacteria in
intestine
Vitamin K - Napthoquinones
Properties
• Fat soluble
• Insoluble in water
• Stable to heat, unaffected
by cooking
• Destroyed by light, strong
acids, alkalis
RDA
No established
recommendation
Hypervitaminosis Excess vitamins A and D
• Hypervitaminosis A - Excess Vitamin A is stored in
the liver. In extreme cases can cause dry skin,
enlarged liver, fatigue, hair loss, headaches,
appetite loss, vomiting, risk of birth defects and
miscarriage.
• Hypervitaminosis D - More common in young
children than adults. Results in high concentration
of calcium in blood. Symptoms - nausea, mental
confusion, vomiting and thirst.
Hand in Hand –
How vitamins help each other
• Vitamin E keeps Vitamin A from being destroyed in
the intestines
• Vitamin D enables the body to absorb calcium and
phosphorous
• Vitamin C helps folate build proteins
• Vitamin B1 works in the digestive system with
niacin, pantothenic acid and magnesium