Discovering Nutrition Chapter 7: Vitamins
disease characterized by softening bones, leading to the bending of the spine, bowing of the legs, increased risk for fractures
Osteomalacia
What does too much vitamin A do to bones?
Too much vitamin A may interfere with the ability of vitamin D to promote Ca absorption and can trigger an increase in cellular activity that breaks down bone.
The liver store 90% of vitamin __ in the body, with the rest found in fatty tissues, lungs, and kidneys
Vitamin A
Only foods of ___ origin contain retinoids.
animal
Vitamin E's most well known function
antioxidant
absorbed by intestinal cells and packaged into lipoproteins and released into lymph system
fat-soluble vitamins
travel through lymph system eventually the bloodstream until they reach the liver
fat-soluble vitamins
sources of vitamin K
food (mostly plant/ green leafy), and bacteria from our colons
form of vitamin K that comes from animal sources and synthesized by our intestinal bactera
menaquinones (K2)
the chemical name for vitamin E. There are 4 (alph-, beta-, gamma-, delta-)
tocopherol
vitamin known for its role in blood clotting and also crucial in bone health
vitamin K
Retinol Activity Equivalent (RAE)
- A unit of measurement of the vitamin A content of a food. - One RAE equals 1 microgram of retinol - What intake recommendations are measured in
what happens to excess fat-soluble vitamins
- accumulate in liver and fatty tissues, building up reserves that can tide you over for weeks or months - generally pose a larger risk of toxicity than excess water-soluble vitamins
what happens to excess water-soluble vitamins
- the kidneys filter out the excess and they're peed out - exception of B12 which gets stored in liver
What are the functions of vitamin E?
1. defends again free radicals 2. protects lungs against oxidative damage from environmental contaminants 3. may help prevent cancer by protecting against DNA mutations 4. may help prevent cardiovascular disease by protecting against lipid peroxidation 5. helps protect eye, liver, breast, and muscle tissues
what are the 3 active forms of vitamin A the body uses?
1. retinol 2. retinal 3. retinoic acid aka Retinoids
Functions of Vitamin A:
1. vision 2. cell production and differentiation 3. skin 4. immune function 5. reproduction 6. bones
the AI of vitamin K for men
120 micrograms per day
RDA of vitamin A for pregnant women who breastfeed
1300 micrograms per day
the active form of vitamin D
25(OH)D
RDA for vitamin D for people ages 1-70 is
600 IU per day
RDA of vitamin A for females over 14 yrs
700 micrograms per day
RDA of vitamin A for pregnant women who do not breastfeed
770 micrograms per day
RDA for vitamin D for people over 70
800 IU per day
the AI of vitamin K for women
90 micrograms per day
body fat holds upto __% of vitamin E reserves
90%
RDA of vitamin A for males over 14 yrs
900 micrograms per day
exposure to light damages which vitamins
A B C?????
Foods with exceptionally hight sources of vitamin A
Beef liver, Carrots, Sweet potato, Chicken liver
Excess vitamin A can lead to
Death, liver damage, bone fracture, skin disorders, birth defects
Deficiency of vitamin A can lead to
Death, night blindness, xerophthalmia, hyperkeratosis, infection, kidney stones, infertility, halt of sperm production
disease in adults that results from vitamin D deficiency
Osteomalacia
disease characterized by a decrease in bone mineral density and the appearance of small holes in bones due to loss of minerals
Osteoperosis
Carotenoid precursors of vitamin A in foods of plant origin, primarily deep colored fruits and vegetables
Provitamin A
support sperm production and fertility
Retinol and Retinal (not retinoic acid)
a bone disease in children that results from vitamin D deficiency
Rickets
disease characterized by "bow legs," "knock knees," and other skeletal deformities
Rickets
dietary deficiency of vitamin ___ is the leading cause of childhood blindness worldwide and often accompanied by PEM
Vitamin A
Fat-soluble vitamin examples
Vitamin A, D, E, K
Water- soluble vitamin examples
Vitamin B, C
beta-carotene
a provitamin that is converted by the body into vitamin A
Dietary need of vitamin D increases with ____, as the ability of the skin to synthesize vitamin D declines
age
roasting destroys 80% of vitamin E in
almonds
Why is vitamin D considered a hormone?
because vitamin D is made in one part of the body and regulates activities in another part of the body
of the carotenoids, ___ supplies the most vitamin A
beta-carotene
triggers electric impulses that the brain interprets as black and white visual images
bleaching process
when light enters the eye and strikes the retina which splits rhodopsin causing it to lose color as it releases opsin and vitamin A.
bleaching process
colorful plant pigments that are precursors of vitamin A
carotenoids
factors that limit fat absorption also limit the absorption of
carotenoids
Good sources of beta-carotene
carrots, winder squash, sweet potatoes, orange colored fruits like cantaloupe, apricots, and mango
When ultraviolet rays of the sun strike you skin, the convert____ to vitamin D
cholesterol
cells in the retina that are sensitive to bright light and are responsible for color vision
cone cells
To increase the absorption of carotenoids one can
consume more dietary fat
the process that increases the rhodopsin concentration in your eyes, allowing them to detect images in the dark better
dark adaptation
replacing lost nutrients
enrichment
About 90% of dietary retinol is in the form of ____.
esters
Major source of dietary vitamin D
fortified foods, oily fish, egg yolk, butter, liver
to add extra nutrients to foods where they wouldn't be found naturally
fortify
the hallmark of vitamin D toxicity
high concentration of calcium in the blood
color-sensitive pigment molecules in cone cells that consist of opsin-like proteins combined with retinal
iodopsin
synthesized/ medicinal form of vitamin K
menadione
the inability of the eyes to adjust to dim light or to regain vision quickly after exposure to a flash of bright light
night blindness
Sources of vitamin
nuts, seeds, vegetable oils, whole grain products, wheat germ oil
the protein rhodopsin is composed of (plus vitamin A)
opsin
vitamins are organic or inorganic?
organic
form of vitamin K that comes from plants
phylloquinone (K1)
inactive forms of vitamins that the body can convert into active usable forms
provitamins aka vitamin precursors
a paper thin tissue lining the back of the eye, where light images are received and relayed to the brain, resulting in vision
retina
work with DNA to differentiate stem cells into different cell types
retinoic acid
key player in vitamin A family
retinol
the main storage form of vitamin A
retinyl esters
purple pigmented aka visual purple
rhodopsin
the cells in the retina that react to dim light
rod cells
characterless cells/ undifferentiated cells aka
stem cells
formation cells whose daughter cells may differentiate into other cell types
stem cells
what happens to the eyes when vitamin A levels are low?
the body cannot re-form rhodopsin and night blindness results
Retinyl esters
type of Performed Vitamin A
along with 2 other hormones vitamin D regulates
urinary calcium excretion, intestinal calcium absorption, and the amount of calcium in the bone
Vitamin ___ deficiency shows up early in the skin and mucus membranes since the turnover of skin cells is rapid
vitamin A
allows night vision and color vision by actually becoming a functioning part of the retina
vitamin A
helps maintain healthy mucous membranes and it supports the generation of lymphcytes
vitamin A
helps produce bone cells and needed for growth and is required for bone remodeling
vitamin A
needed to change incoming light to visual images and keep the eye's surface healthy
vitamin A
needed to produce immune cells to attack invaders
vitamin A
replacing epithelial cells requires vitamin ___
vitamin A
vitamin that is crucial for vision and renewing cells
vitamin A
exposure to light damages which vitamins
vitamin A, B (riboflavin), C
This vitamin is considered both a vitamin and a hormone
vitamin D
maintains blood calcium and phosphorus levels within normal range
vitamin D
this vitamin is involved in the regulation of insulin formation and secretion, which suggests a role in blood sugar maintenance
vitamin D
this vitamin plays a role in preventing cancer cells from dividing and has anti-inflammatory properties
vitamin D
vitamin that helps regulate blood levels of calcium and is essential for bone health
vitamin D
this vitamin helps prevent free radical damage
vitamin E
antioxidants that help protect cells from damage
vitamin E and carotenoids
newborns are routinely given injections of vitamin __ because they still lack the bacteria in their intestine, and because breast milk has little of this vitamin, breastfed babies are especially vulnerable
vitamin K
this vitamin is essential for blood clotting
vitamin K
toxicity is rare because this vitamin is readily excreted as compared to other fat-soluble vitamins
vitamin K
dissolved in the watery compartments of foods and intestinal cells absorb them directly into the bloodstream
water-soluble vitamins
a condition caused by vitamin A deficiency that dries the cornea and mucous membranes of the eye
xerophthalmia
