ch 8 Flashcards
complex, carbon based structure
vitamin
No caloric value
Essential
Deficiency without
We can make some but not all
Needed in very small amounts (mg/micrograms)
For optimal growth and health
vitamin
Water soluble
b vitamins, vitamin c
water soluble characteristics
Absorbed directly into bloodstream
Excreted in the urine
More easily lost in cooking
Still stay below UL
fat soluble
A, D, E, K
Vitamin A key functions
Low-light vision
Maintain epithelial cells, healthy immune function
Gene expression (activate or deactivate genes)
fat soluble characteristics
Transported via chylomicrons
Stored in body tissues
Toxicities are more serious
beta carotene
“pro-vitamin”- body can convert it to vitamin A
b vitamins
Thiamin
Riboflavin
Niacin
Folate
Vitamin B12
Vitamin B6
Biotin
Pantothenic acid
vitamin D
Maintain blood calcium and phosphorous levels
vitamin E
Scavenges and stops free radicals in body (common, but not highly-reactive atoms that can damage the body due to an unpaired electron)
Other antioxidants are Vit C and beta carotene
Vitamin K
helps synthesize blood clotting proteins
vitamin C
Collagen synthesis, maintaining connective tissue
Wound healing
Antioxidant
B vitamins roles in common
Act as coenzymes in cellular functions
Thiamin, riboflavin, and niacin release energy from macros
Folate: Dna/Rna synthesis, cell division
Vit 12: protects nerve fibers
vitamin A food sources
Orange fruits and veggies
Leafy green veggies**
Fortified milk
Liver
factors affecting vitamin D status
Age/
Far northern or southern latitudes?
Air pollution?
Clothing?
Dark skin pigmentation?
Sunscreen?
polar bear liver provides
140x RDA for vitamin A
Vitamin D food sources
Salmon and tuna
Fortified milk and cereal
THE SUN
Our body makes it when we are exposed to the sun
UV light activates
folate food sources
Veggies, especially leafy greens
Citrus fruits
riboflavin food sources
Enriched grains
Milk
vitamin e food sources
Plant oils, nuts, seeds
thiamin food sources
Enriched grains
Pork and other protein foods
riboflavin sensitivity
UV light, irradiation destroy riboflavin
Store milk in cardboard or opaque containers
niacin foods sources
Enriched grains
Mostly meat
B12 food sources
Animal products
Fortified soymilk and cereals
vitamin C food sources
Colorful fruits and veggies
Vit D deficiency
kids: rickets; adults: osteomalacia:
soft bones
Vit A deficiency
XEROPTHALMIA: night blindness; leads to total blindness
KADE vitamins are..
fat soluble
darker skin indicates
less vitamin D
vitamin K deficiency
Hemorrhaging
Rare except in infants (does not cross placenta wall, low in breastmilk, sterile gut)
Vit K injection given first few days of life
thiamin deficiency
(beriberi)
Symptoms include muscle weakness, tingling, edema (wet only)
Common in alcoholics (wenicke-korsakoff)
riboflavin deficiency
Cheilosis: cracking and redness at corners of mouth
Inflamed, painful, smooth, purplish red tongue
Niacin deficiency
pellagra
The four D’s
Dermatitis (skin rash)
Diarrhea
Dementia
Death
vit c is an
antioxidant
vit k is
not an antioxidant
folate toxicity
Hides signs of B12 deficiency
B12 activates folate, deficiency in either can cause anemia
Folic acid is already activated so anemia isn’t noticed>neuro problems
Other adults and vegans should be especially aware
vit c TOXICITY
GI discomfort and diarrhea seen primarily at very large doses (3 g/day)
UL= 2 g/day
folate deficiency
anemia
Cells are unable to divide:
Mega elastic, big, bloated cells that cannot deliver oxygen as efficiently
folate deficiency during pregnancy
Baby at risk for neural tube defects
Neural tube closes in first 28 days
Folate fortification since ‘96 has significantly reduced NTD
Recommendation for women of childbearing age: 400 mcg/day of folic acid through supplements
VITAMIN b12 deficiency
Nerve degeneration, death
Anemia
Same as folate
Can. be from lack of intrinsic factor
vit c deficiency
scurvy (george a smith)
Easy bruising, slow wound healing
Pinpoint hemorrhages
Bleeding gums
vit a toxicity
SERIOUS
Birth defects
Liver failure, death
beta carotene toxicity
hypercarotenemia
Misinterpreted at jaundice sometimes
Orange skin
Eating a whole bag of carrots
vit D toxicity
Not from overexposure to sunlight
Elevated blood calcium
Calcification of soft tissues
vit K toxicity
Rare, usually from supplements
Opposes anti-clotting medications
niacin toxicity
Skin flushing, hives, rash
ALL B12 VITAMINS ARE
COENZYMES
loss of vitamins occurs:
Heat/cooking, air/oxygen, light, and water
can cans retain nutrient?
yes
is fresh still best?
yes
