Chapter 10: Vitamins Flashcards
Vitamins can be destroyed by what 3 things?
- heat
- light (ex fresh squeezed oj)
- oxygen
Fat soluble vitamins
ADEK
water soluble vitamins
B and C
Bioavailability of vitamins is influenced by what 3 things?
- efficiency of digestion
- Previous nutrient intake and nutrition status
- preparation
Water soluble vs. fat soluble
Absorption
WS: directly into blood
FS: first to lymph then blood
Water soluble vs. fat soluble
Transport
WS: travel freely
FS: need transport protein
Water soluble vs. fat soluble
Excretion
WS: kidneys detect and remove xs in urine
FS: remain in fat-storage sites. not readily excreted
Water soluble vs. fat soluble
Toxicity
WS: possible to reach toxic levels from supplements
FS: likely to reach toxic from supps
Water soluble vs. fat soluble
Requirements
WS: needed freqently
FS: Needed periodic
How to remember the B vitamin names?
TRaiN
Thiamin
Riboflavin
Niacin
Main 2 purposes of B1/thiamin
- Part of the coenzyme needed to convert pyruvate to acetyl-CoA
- Needed for nerve and muscle activity
B1/ Thiamin deficiency called
Beriberi
dry form- verve damage
wet form- cardiovasvular damage and edema
What animal product is very high in B1/thiamin?
pork
Main purpose of B2 RIboflavin? Deficiency causes?
coenzyme in energy metabolism
deficiency causes inflammation of membranes
Good source of B2/Riboflavin? What destroys it?
Dairy products
UV light destroys it
What vitamins start with “nico”?
B3/Niacin
How many structures does B3/niacin have? Purposes?
2; both involved in metabolism
How do we make B3/niacin? How do they know how much we need?
We make it from the AA tryptophan only after protein needs met
RDA is in niacin equivalents
B3/ Niacin Deficiency and key points
Pellagra
4Ds: diarrhea, dermatitis, dementia, death
Is niacin in corn?
Yes, but no bioavailable
What vitamin starts with “pyri”
B6
Vitamin B6 is most known for
protein metabolism
transfers amino groups to nonessential amino acids
stored in muscle
White flour and rice are enriched with which 5 things?
- B1
- B2
- B3
- folate
- iron
B6 toxicity can cause
neurological damage
B9/Folate vs. folic acid
folate- dietary folate
folic acid- synthetic folate that’s better absorbed
Folate and ___ work hand in hand. How so?
B12
B12 breaks off methyl from folate to activate. that methyl then activates B12
What are the main 2 purposes of folate?
- transfers carbon compounds that convert B12 to coenzyme form
- Synthesizes DNA and RNA
What happens to excess folate
the liver puts it into bile which is then excreted or absorbed
Folate deficiency causes? who at risk and why
neural tube defects and spina bifida and cleft lip
Hispanic women have a gene that requires them to have more but they get less because of masa flour
High doses of B9/folate can obscure what
a B12 deficiency
Vitamin B12 cobalamin roles
- Protects nerve function
- Protects bone health and avtivity
who is at risk for b12 deficiency?
vegans bc only in animal protein
