Chapter Five

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Chapter Six- Part 2
The Fat Soluble
Vitamins
NUT SCI 142 © Spring 2005
Karen Lacey, MS, RD, CD
Categories

WATER SOLUBLE (9)
– Thiamin (B1)
– Riboflavin (B2)
– Niacin (B3)
– Folate (folic acid)
– Vitamin B6
– Vitamin B12
– Pantothenic Acid
– Biotin
– Vitamin C (ascorbic
acid)

FAT SOLUBLE (4)
–
–
–
–
Vitamin A
Vitamin D
Vitamin E
Vitamin K
ANTIOXIDANTS
(Vit C, E, beta-carotene)

Free radicals (unstable
oxygen compounds)
– Smoking
– Sunlight
– Chemical reactions
in body
– Environmental
pollution


Cause damage
– Enzymes
– Cell membrane
– DNA
– Oxidized LDLcholesterol
Antioxidants
– Donate O2 to make
stable
8. Vitamin A - Roles




VISION
Light is transformed
into nerve impulses so
brain can interpret
Transformers are
pigment molecules in
retina
Retinal is part of the
pigment
Retinal is formed from
Vitamin A
CELL DIFFERENTIATION
 Skin
 Epithelial cells (linings
of intestine)
IMMUNITY
 Protective effect
ANTIOXIDANT
 Beta-carotene
Vitamin A (cont)
FORMS IN FOOD


Pre-formed Vit A
– Active form
– Animal foods (liver,
fortified milk,
chesses, egg yolk)
Beta-carotene
– Precursor
– Plant foods
(carotenoids)
RDA





800 to 1000 RE
RE = Retinal
Equivelant
How much retinal the
body can make from
the two forms
Carotene (orange
foods)
Retinol (yellow foods)
Vitamin A – Problems



DEFICIENCY
Night blindness
Blindness
Infectious
diseases
(especially
measles)






TOXICITY
Joint pain
Dry skin
Fatigue
HA, weakness
Nausea
Supplements of preformed active Vit A
9. Vitamin D
ACTIVE
ROLES


Bone growth
Helps increase blood
levels of calcium
–
–
–

Increase absorption
from gut
Decrease loss from
kidney
Move calcium from
bones
Acts like hormone


Liver – makes one
form
Kidney – makes active
form
DRI


5- 10 ug
Based on growth and
development (more for
children)
10 ug for adults
Vitamin D (cont)
DEFICIENCY

Rickets
–
–

Children
Bowed legs
Osteomalacia
–
–
Adults
Softening of bones
TOXICITY


High blood levels of
calcium
Kidney stones
Vitamin D – sources




Sunlight – begins the conversion of an
inactive form to active form (5-15 minutes)
Foods – Animal
Same as preformed Vitamin A
– Eggs
– Fortified milk
– Margarine
Shrimp
10. Vitamin E

ROLE
Antioxident




DRI
15 mg – adults
One of most
popular
supplements



FOODS
Vegetable oils
Nuts and seeds
Wheat germ
Green leafy
vegetables
Mayonnaise
Vitamin E (cont)
DEFICIENCY



Muscle wasting
Red blood cell
breakage
Anemia
TOXICITY


> 1000 mg
Increase bleeding
11. Vitamin K



ROLE
Blood clotting
Used in synthesis
of 4 – 13 proteins
used to make blood
clot
Works with Vit D to
make bone protein



DRI
60-80 ug
DEFICIENCY
Bleeding
Decreased bone
calcium
Vitamin K – sources


Intestine – bacteria synthesize
Foods
– Liver
– Green leafy & cabbage type vegetables
– Garbanzo beans
– Eggs
– Milk
Vitamin Preservation





Shop frequently for fruits and vegetables
Store foods in refrigerator (cold preserves
nutrients)
Cut and peel just before serve or eat
Use liquid from cooked and canned vegetables
Steam or microwave
Vitamin/Mineral Supplements – Who?






Very low calorie diets
Strict vegetarians
Pregnant and breastfeeding
Childbearing age (folate)
Elderly
Heart disease or at risk AND do not consume
adequate antioxidents and B vitamins
Vitamin/Mineral Supplements – What?





Price not indication of quality
Label for USP (US Pharmacopeia)
Contains both vitamins and minerals with 100150 X RDA
Be wary of claims “natural”, contain herbs,
Child proof caps
Phytochemicals


Physiological active compounds
found in plants that are not nutrients
but appear to help promote health
and reduce risk for cancer, heart
disease and other conditions
Brilliant color
Phytochemicals
Antioxidents
 Decrease blood pressure
 Decrease blood cholesterol
 Prevent cataracts
 Prevent osteoporosis
 Combine benefits with vitamins,
minerals, fiber, low-fat, low calories

Phytochemicals



Allyl sulfides
– onions
Carotenoids
– Beta-caratene
– Lutein & zeaxanthin
– Lycopene
Indoles
– Cruciferous
vegetables



Flavonoids & phenols
– Fruits
– Green tea
– Chocolate
Phytoestrogens
– Isoflavones – soy &
legumes
– Lignan –flaxseed
Saponins
– Potatoes
WEB SITES



http://www.5aday.com/
www.nccam.nih.gov
http://www.fda.gov/
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