Exam #3 (Part 1- Vitamins Overview & Fat-soluble Vitamins)
A, D, E, K
fat soluble vitamins
liver; adipose tissue
fat soluble vitamins are stored in the ______ and ______ ______ and are not readily excreted (except for K)
chylomicrons
fat-soluble vitamins are packaged into ___________ and enter into the lymphatic system; from there they are taken to the liver as part of chylomicron remnants; once in the liver, packaged into lipoproteins and exported to the blood stream
bile; fat
the absorption of fat-soluble vitamins in the small intestine requires _____ and the presence of dietary _____
beta-carotene
the carotenoid with the most vitamin A activity
liver damage
toxicity of vitamin A can cause _____ ______
free radical
unstable compounds that have one or more unpaired electrons and can damage electron-dense cell components such as DNA, proteins, and cell membranes
dermatology
vitamin A analogs in __________
epithelial; oxidative
vitamin A has an immune function because it aids growth, development, and maintenance of ________ cells and protects WBCs from _________ damage
blood clotting
vitamin E is relatively nontoxic, but megadose supplements can cause impaired ______ ______
menquinones
vitamin K from fish oils and meats; also synthesized by bacteria in the colon
not metabolized
vitamins are ____ ___________
stomach
vitamins are released from foods in the _________
water-soluble
vitamins that are least likely to reach toxic levels since they're excreted
vitamins A and D
vitamins that are most likely to reach toxic levels (with supplementation)
water soluble vitamins
vitamins that dissolve in watery components of food and the body; limited amounts are stored; needed in small amounts daily; excreted when consumed in large amounts; destroyed when exposed to air, water, or heat
fat soluble vitamins
vitamins that need lipids to be absorbed; stored in the body and used when dietary intake falls short; chronic excesses can be toxic; tend to be more stable, but some are lost with cooking
1912; Casimir Funk
vitamins were first named vitamine in _______ by _______ _______; Vital=necessary for life; Amine- a type of nitrogen containing substance (later changed to vitamin because it was discovered that no all substances were amines)
B, C, Choline
water soluble vitamins
directly absorbed
water soluble vitamins are _____ _____ in the small intestine and released into the blood stream
liver
water soluble vitamins are absorbed directly into the blood stream and taken to the _______
urine
water soluble vitamins are not often stored (except for B6 and B12) and are readily excreted in the ________
osteomalacia
Vitamin D deficiency that causes abnormal softening of bones in adults
vitamin D absorption, transport, and activation
1: In the small intestine, inactive form is packaged into chylomicrons and enters the lymphatic system 2: Transported to circulatory system and taken to liver 3: Bound to a binding protein for transport and storage 4: Metabolized in liver 5: Further metabolized in kidneys 6: Calcitrol bings to vitamin D receptors on various tissues
food sources of vitamin D
Excellent: fatty fish (sardines and salmon); fortified milk and soy milk, cod liver oil, mushrooms ; Good: egg yolk and breakfast cereals
vitamin D
Fat-soluble vitamin that can sometimes become deficient
15 micrograms/day
RDA for Vitamin D (assuming minimal sun exposure)
teratogen
Vitamin A is a _________, meaning it can cause birth defects if pregnant mothers take in excess levels
rickets
Vitamin D deficiency in children that can cause an enlarged head, joints, and ribcage and bowed legs
supplements
__________ are not a substitute for a healthy diet; lack of fiber and phytochemicals, limited amounts of some nutrients; excess can lead to toxicity
supplementation
___________ is more likely to lead to toxicity than food sources
vitamin
a complex organic compound that regulates certain metabolic processes; essential; occurs naturally in foods
100%
a dietary supplement should be no more than _____ Daily Value and should not exceed UIs; always check for USP certification
vitamin E
a function of ________ ____ is that it is an antioxidant, stopping lipid peroxidation damage to cell membranes
small intestine
absorption of vitamins occurs in the ______ _______
oxidative stress
accumulation of free radicals beyond the body's ability to remove them
vitamin D toxicity
arises from supplementation (not natural dietary sources or excess sun exposure); can cause calcium deposits in organs, nausea/vomiting, bone demineralization, weakness and joint pain, kidney dysfunction, or death
retinoids
beef liver; fortified dairy (milk, margarine)
fruits and vegetables
beta-carotene is consumed from
food sources of vitamin K
broccoli, asparagus, cabbage, brussels sprouts, dark green leafy vegetables (mustard and turnip greens, kale, spinach), safflower oil
bone health
calcitrol (vitamin D) helps maintain blood levels of calcium and phosphorus by increasing intestinal absorption and increasing their release from bone which maintains ______ ______
Vitamin D deficiency
causes of _______ _____ ________ could be fat malabsorption, dark skin pigmentation, low milk intake, minimal sun exposure, or liver/kidney disease
Vitamin D3
cholecalciferol; synthesized in skin from sun exposure
A
citizens of underdeveloped countries, impoverished and older adults, alcoholics, and individuals with fat malabsorption are at risk for vitamin ___ deficiency
vitamin D
classified as a vitamin and a prohormone; active form is Calcitrol; Precursor to cholesterol
antioxidants
compounds that stop the chain reaction started by free radicals; function in lipid rich areas where lipid peroxidation by free radicals can damage cell membranes and in enzyme systems that require minerals to function
hyperkeratosis
condition in which vitamin-A deficient epithelial cells produce keratin, a tough protein found in hair, nails, and the outmost layer of skin; causes impaired growth and immunity
vitamin A
deficiency in ________ ___ can lead to conditions that progress to blindness like night blindness, conjunctival xerosis, bitot's spots, and xerophthalmia
water soluble; fat soluble
deficiency of ______ _______ vitamins can begin from weeks to months, while deficiency of ______ _______ vitamins begins months to years
rarely; prolonged
deficiency of fat-soluble vitamins _______ occurs and there is a ________ time to deficiency symptoms
rare
deficiency of vitamin E is _____, but some common causes are fat malabsorption, smoking, preterm birth, genetic defect in lipoprotein synthesis
antibiotics
deficiency of vitamin K is rare, but can occur with prolonged use of ____________
eye disease, cancer, and cardiovascular disease
diets high in carotenoids can reduce risk for
did not
epidemiological study found that taking supplements of isolated beta-carotene ____ ____ reduce risk of lung cancer; concluded that it must me consumed in diet to be effective
Vitamin D2
ergocalciferol; occurs naturally in foods or in fortified foods and supplements
age-related macular degeneration
eye disease resulting in changes in the macula of the eye, causing distorted vision; beta-carotene can help reduce risk
vision
function of vitamin A; retinol (form of vitamin A) is needed in the visual cycle; helps rods in retina to adapt to poorly lit environments
vitamin D
functions in immunity, secretion of insulin, renin, and PTH, and the cell cycle regulation
vitamin K
functions of ________ ___ include bone metabolism and activation of blood clotting factor
vitamin D3 synthesis
geographical location, time of day, season of year (Nov, Dec, Jan, Feb= no conversion of D3 to usable Vitamin D), age, melanin pigment in skin, sunscreen, and air pollution are all factors that effect ________ ____ ________
newborns
given vitamin K after birth to prevent deficiency
10-19%
good source of nutrient
20% or higher
high or excellent source of nutrient
C (or A)
if you do not consume any fruits or vegetables, it's essentially impossible to get vitamin ____
toxicity
occurs when the intake of vitamins exceeds the UL
phylloquinone
plant form of vitamin K
retinoids
preformed vitamin A; a family of 3 compounds called vitamin A
carotenoids
sweet potatoes, carrots, kale, broccoli, spinach, pumpkins, apricots, mangos, cantaloupe
beta-carotenes
protecting tissues from free radical damage; reducing risk of cataracts; and reducing risk for lung/breast cancer are all functions of _________
carotenoids
provitamin A; compounds that can be converted into vitamin A
food sources of vitamin E
seed oils (canola, safflower, sunflower), peanuts, hazelnuts, almonds, peanut butter, sunflower seeds, wheat germ, and avocado
sun; food
we get more vitamin D from the _____ than _____
ultraviolet light
what vitamin D3 needs exposure to in order to convert the inactive form into an active form
weeks
with low intake or no intake, water soluble vitamin deficiency symptoms can appear within _______
carotenemia
yellowing of the skin that results from excess beta-carotene in the body