ch 67 highlights Flashcards
recommended dietary allowance
requirements of nearly all healthy individuals
differ for males and females
increase for women who are pregnant or breastfeeding
Change as people grow older
estimate of the average daily intake required to meet nutritional needs
AI - adequate intake
only estimates
You need a EAR to make a
RDA
If you cannot make an RDA, you get a
AI
fat soluble vitamins
A, D, E, K
water soluble vitamins
C and B
the level of intake that will meet nutritional requirements for 50% of healthy individuals
Estimated Average Requirement
too much vitamin A causes
increases r/o osteoporosis in postmenopausal women and an cause birth defects when the vitamin is taken early in pregnancy
too much vit E in older people with chronic health problems
increases r/o death
Nutrition experts recommend vit B12 (cyanocobalamin) for all
people over 50 years
Nutrition experts recommend folic acid for all
women of childbearing age
Nutrition experts recommend vit d (plus calcium)
for postmenopausal women and others at risk for fractures
smoking increases risk of what vit def
vit c
vegan diets need what supplements
A
B2
B12
D
Breastfeeding infants need what supplement
Vit D
vitamin a use
adaptation to dim light embryogenesis spermatogenesis immunity growth skin and mucous membranes
Vit A food sources
dairy products meat fish oil carrots cantaloupe mangoes spinach tomatoes pumpkin sweet potato
what is the first indication of a vit a def
night blindness
can lead to blindness
increased levels of vit A will block what vit
vit D
excess vit A can lead to
birth defects
liver injury
bone-related disorders
tox Vit a symptoms
vomiting jaundice hepatosplenomegaly skin changes hypomenorrhea elevation of Intracranial pressure
disappear after vit A withdrawal
Vit D plays a critical role in
calcium metabolism and maintenance of bone health
Vid d def in children
rickets
Vit d def in adults
osteomalacia
Vit E uses
antioxidant
role in protecting blood cells from homolysis
Vit E sources
vegetable oils nuts wheat germ whole grain products mustard greens
Vit E def
ataxia
sensory neuropathy
areflexia
muscle hypertrophy
high dose vit E does what
increases risk for hemorrhagic stroke by inhibiting platelet aggregation
increased cancer risk
high doses of antioxidants may cause cancer or accelerate cancer progression
High dose vit E in combination with vit C has what effects on the benefits of exercise on insulin sensitivity
can blunt the beneficial effects of exercise on insulin sensitivity
Vitamin K actions
needed to coagulate blood
1) correction or prevention of hypoprothrombinemia and bleeding caused by vit k deficiency
2) control of hemorrhage caused by warfarin
sources of Vit K
met through dietary sources, synthesized by intestinal flora
vit K may be low in who
newborns due to the intestinal colonization of the gut is not complete until several days after birth
vit K def causes
produces bleeding tendencies
if severe, spontaneous hemorrhage may occur
what disease processes can decrease vit k uptake
obstructive jaundice
malabsorption syndromes - sprue, celiac disease, cystic fibrosis of the pancreas
newborns receive what injection after delivery
Vit K1 (phytonadione)
Vit k tox can cause
hyperbilirubinemia, hemolytic anemia and jaundice in newborn
oral form of vit k is not toxic in adults
ascorbic acid (Vit C)
synthesis of adrenal steroids
conversion of folic acid to folinic acid
regulation of the resp cycle in mitochondria
facilitates absorption of dietary iron
the only established indication for Vit C is
prevention and treatment of scurvy
for severe, acute def of vit c what route of administration is recommended
Vit C
studies have shown that large doses of Vit C do/do not reduce the incidence of colds
do not, although the intensity or duration may be decreased slightly
sources for vit c (ascorbic acid)
citrus fruits and juices tomatoes potatoes strawberries melons spinach broccoli
OJ and lemon juice are especially rich sources
symptoms of scurvy
faulty bone and tooth development loosening of teeth gingivitis bleeding gums poor wound healing hemorrhage into muscles and joints ecchymoses
though not a common cause of deficiency, smoking creates an increased need for
vit c
symptoms
nausea
abd cramps
diarrhea
what vit tox causes these symptoms
Vit C tox
Vit B3 (Niacin) roles or nicotinic acid
plays a role in cellular respiration
sources of niacin (nicotinic acid) aka vit B3
liver poultry fish potatoes peanuts cereal bran cereal germ
Pellagra - rough skin
- dermatitis-scaling, cracking of skin
abd pain
diarrhea
soreness of tongue and mouth
irritability
insomnia
memory loss
anxiety
dementiaNiacin def symptoms
all symptoms can be reversed with niacin replacement therapy
Niacin/Vit B3 (nicotinic acid) tox
vasodilation
flushing
dizziness
nausea
Vit B12 (riboflavin) uses
acts as a coenzyme for multiple oxidative reactions
sore throat angular stomatitis (cracks in the skin at the corners of the mouth)
Vit B12 (riboflavin) def
later symptoms of Vit B12 (riboflavin) def
cheilosis (painful cracks in the lips)
glossitis (inflammation of the tongue)
vascularization of the cornea
itchy dermatitis of the scrotum or vulva
Vit B12 (riboflavin) tox
excess is excreted in the urine
Vit B12 (riboflavin) can help prevent
migraine headaches - prophylactic effects do not develop until after 3 months of treatment
Vit B1 (Thiamine) actions
coenzyme for carbohydrate metabolism
Vit B1 (Thiamine) sources
enriched fortified or whole grain products esp breads and ready to eat cereals
fish (esp tuna, salmon and anchovies)
liver
chicken
pork
beef
lamb
Vit B1 (Thiamine) def produces
wet beriberi
dry beriberi
primary symptom is fluid accumulation in the legs
cardiovascular complications
rapidly progress to circulatory collapse and death
wet beriberi (easier to fix)
neurologic and motor deficits (anesthesia of the feet, ataxic gait, footdrop, wristdrop)
dry beriberi (harder to fix)
Wernicke-Korsakoff syndrome
Thiamine deficiency (B1) in people with chronic alcohol consumption
neurologic and psychologic manifestations nystagmus diplopia ataxia inability to remember the recent past
Wernicke-Korsakoff syndrome
tox for Vit B1 (Thiamine)
devoid of tox symptoms
Vit B6 (Pyridoxine) action
coenzyme in the metabolism of amino acids and proteins
Vit B6 (Pyridoxine) sources
fortified, ready to eat cereals meat fish poultry white potatoes and other starchy vegetables non-citrus fruits beef liver soy based products
seborrheic dermatitis anemia peripheral neuritis convulsions depression confusion
Vit B6 (Pyridoxine) def
dietary def of Vit B6 (Pyridoxine) is rare except among people
who abuse alcohol on a long term basis
People who are predisposed to neuropathy like people with diabetes or alcoholism should receive daily
Vit B6 (Pyridoxine) supplements
infants with irritability
convulsions
anemia
might be deficient in
Vit B6 (Pyridoxine)
permanent cognitive deficits unless treated early
ataxia
numbness to hands and feet
Vit B6 (Pyridoxine) tox from high doses
in low doses no tox
Vit B12 (Cyanocobalamin) action
carb and fat metabolism
protein synthesis
synthesis of DNA
formation of blood cells
sources of Vit B12 (Cyanocobalamin)
clams liver meat fish poutry eggs milk fortified processed cereals
Vit B12 (Cyanocobalamin) def results in
megoblastic anemia (ie: pernicious)
macrocytic anemia
neurologic damage
what populations are at high risk for Vit B12 (Cyanocobalamin)
bariatric surgery
strict vegan diet
age associated gastric atrophy
Most common presenting symptom of Vit B12 (Cyanocobalamin) def
Glossitis
Vit B12 (Cyanocobalamin) def symptoms
-impaired cognition
-mood alterations
-psychosis
peripheral sensory deficits with weakness
ataxia
extrapyramidal symptoms
GI effects
Glossitis
Vitamin B9 occurs in 2 forms
folic acid
folate
Which B9 form is the naturally occurring form of the vit
Folate
Which B9 form is the synthetic form
Folic acid which is more stable than folate
Folate functions as a
coenzyme in the synthesis of nucleic acids (DNA and RNA). Has a role in the metabolism of amino acids
Folic acid supplements are used to prevent
neural tube defects
Sources of folate
Beef liver is the highest
spinach
black eyed peas
asparagus
green leafy vegetables
all enriched grain products must be fortified with folic acid
pregnancy recommendation for folic acid intake
all women who are capable of becoming pregnant consume 400-800 ug of supplemental folic acid each day in addition to the folate they get from food
def in folic acid or vit B12 can result in megaloblastic anemia and neurologic damage. Deficiency in B9(folic acid) occur in concert. In instances were both are responsible what can be done?
high doses of folate can reverse the anemia but they cannot reverse the neurological damage that occurs secondary to vit B12 def
Vit B5 (Pantothenic acid) and supplemental use
OTC is available but there is no therapeutic use for this supplement bc def does not occur, no supplement is needed
Vit B5 (Pantothenic acid) sources
is present in virtually all foods
Vit B5 (Pantothenic acid) tox
no tox
Vit B7(Biotin) actions
involved in metabolism of carbs and fats
Primary reason people take Vit B7 (Biotin)
treat hair loss and improve skin conditions
Vit B7 Biotin sources
wide variety of foods
synthesized in intestinal bacteria
dermatitis conjunctivitis hair loss muscle pain peripheral paresthesias lethargy hallucinations depression
Vit B7 Biotin def
Vit B7 tox
no tox
what will increase absorption of iron
Vit C (OJ)
What supplement is given in high doses to treat hyperlipidemia
Nicotinic acid - causes vasodilation
What supplement is used to reduce cholesterol
Niacin
nicotinamide
no vasodilation but does not help with cholesterol
B6 interferes with
levodopa (Parkinson med)
