vitamins and minerals pt 2

Question 1

Vitamin C

Answer 1

• Vitamin C is a water soluble vitamin that primarily
functions as an antioxidant
– Donates an electron to free radicals to stabilize them and prevent them from destabilizing other important molecules
– Protects cellular membranes from being oxidized
– Protects LDL cholesterol from being oxidized
– Enhances immunity (protects white blood cells from oxidative
damage that takes place when fighting infection)
– Also acts as an antioxidant by regenerated oxidized vitamin E
• Also plays a role in regulating thyroid hormone
production
• Critical to the synthesis and maintenance of collage

Question 2

why is weaving of connective tissue necessary

Answer 2

strong, healthy connective tissue
collagen must interveave or can tear apart
collagen is coenzyme for procollagen
bleed easily or have easy wounding

Question 3

Vitamin C deficiencies rare in developed countries
____ is most common deficiency disease

AE

Answer 3

Scurvy

Adverse effects of Vitamin C are rare as excess is
excreted in the urine, very large doses of supplements
can cause
– Nausea
– Diarrhea
– Nosebleeds
– Abdominal cramps
– Harmful for people with hemochromatosis* (can’t transport iron, accumulate it and increases heart attack)

RDA for people 19 years or older
– 90 mg/day for men, 75 mg/day for women
– Smokers require 35 mg/day more
women with contraceptives need more of it

Question 4

Vitamin A
retinal combines protein in rods and cones (opsin) to make rhadopsin, once light hits eye, retin dissociates with opsin and lets brain know therei s light

Answer 4

Vitamin A is a fat soluble vitamin that also functions as
an antioxidant and has 3 active forms
– Scavenges free radicals and protects LDL cholesterol from being
oxidized
– Essential for healthy vision
– Important for cell differentiation
– Reproduction (sperm production and fertilization)
– Bone growth

Question 5

3 types of Vit A

Answer 5

retinol, retinal, retinoic acid

retional: vision, sexual reproduction, bone health, immune fxn
same for retinal

retinoic acid:L cell diff, bone health, immune function

retinal combines protein in rods and cones (opsin) to make rhadopsin, once light hits eye, retin dissociates with opsin and lets brain know therei s light

Question 6

Vitamin A deficiency is associated with the following

why is it narrow window?

• RDA for people 19 years or older
– 900 μg/day for men, 700 μg/day for women
FYI

beef liver, beta cartoine can be converted to vit A

Answer 6

– Night blindness
– Hyperkeratosis
– Impaired immunity, failure of normal growth

Vitamin A is highly toxic and toxicity can be seen at doses 3-4x the RDA (mainly from supplements)
– Teratogenic (can cause spontaneous abortion)
– Fatigue
– Loss of appetite
– Hair loss & skin disorders
– Nausea & abdominal pain

Question 7

The primary vitamins regulating bone health are
vitamins D and K

Vitamin D

role

Answer 7

• Vitamin D is a fat soluble vitamin that plays an
important role in bone health (also a hormone)
– Regulates blood Ca2+ levels (regulates calcium & phosphorous
absorption from the small intestine)
– Stimulates osteoclasts
– Can also contribute to bone calcification

7-dehdrocholesterol in melanocytes skin –> UV light convert it to cholecalciferol, conversion in liver to caclidiol –> kidneys convert to calcitriol

Question 8

Vitamin D

which foods

• RDA for people 19 years or older
– 600 IU/day for both men and women
slide 45 not tested

Answer 8

• Most foods naturally contain little vitamin D
– Cod liver oil & fatty fish (e.g. salmon, mackerel)
– Fortified milk (100 IU/cup)
• Vitamin D deficiency is associated with the following
– Loss of bone mass
– **Rickets (children - bowed legs, knocked knees), osteomalacia (adults - fractures)
– Glucocorticoids can alter vitamin D metabolism
• Vitamin D adverse effects include (mainly from
supplements)
– **Hypercalcemia (can lead to bone loss)

Question 9

Vitamin K

bone health

Answer 9

• Vitamin K is a fat soluble vitamin that plays an important role in both bone health and blood coagulation
– Required for production of osteocalcin
– Acts as a coenzyme for a number of proteins
(prothrombin) involved in blood clotting
• Plant form = Phylloquinone
• Animal form = Menaquinone
• Produced by our gut flora

• bone abs and remodelling by osteocalcin
• not shown that deficiency affects bones
• important in blood clotting

Question 10

Vitamin K
main sources

inject vit K to newborns as they do not have the gut flora yet

• RDA for people 19 years or older
– 120 μg/day for men, 90 μg/day for women

Answer 10

• Food sources high in vitamin K include the following
– Kale
– Turnips
– Brussel sprouts
– Broccoli
green leafy vegtables

• Vitamin K deficiency is associated with the following
– Excessive bleeding (impaired blood clotting)
• No known adverse effects from Vitamin K excess

Question 11

Should you Drink Vitamin Water?

Answer 11

• Regular vitamin water has added sugars
• If you are eating a healthful diet that is adequate, moderate, balanced and varied
– You will be for most part consuming vitamins at the required RDA for maintaining healthy body function

Question 12

minerals

- anything not talked about not in test

Answer 12

Minerals - required for body processes
– regulate fluid and energy production
– essential for bone and blood health
– remove harmful metabolic byproducts
– major (>100 mg/day) and trace (<100 mg/day)

Question 13

Fluid Balance

Minerals important in regulating fluid balance include;

Answer 13

– Sodium 1.5g/day
– Potassium 4.7
– Chloride 2.3
– Phosphorous 700

Question 14

Sodium role

Answer 14

Sodium is the major positively charged nelectrolyte in extracellular fluid
– Regulates fluid balance and blood pressure
– Assist in the initiation and transmission of nervous signals
– Nerve impulses in muscle are the impetus for muscle contraction

Question 15

Sodium Toxicity & Deficiency

Answer 15

Hypertension (especially when combined with low potassium intake)
– Deficiency is rare but can lead to hyponatremia (intense physical activity, severe diarrhea)

hyponatremia, seizures, coma, death?

Question 16

Potassium role

Answer 16

• Potassium is the major positively charged
electrolyte in intracellular fluid
– Also regulates fluid balance and the transmission of nerve impulses and muscle contraction

Question 17

Potassium Toxicity & Deficiency

Answer 17

– Hyperkalemia (sinus bradycardia, cardiac arrest)
– Hypokalemia is rare (people taking diuretics that are not potassium sparing are at risk)
– A high Na+/low K+ is thought to be a major risk factor for hypertension

inject k into heart for cardiac arrest

Question 18

Chloride role

Answer 18

• Chloride is a negatively charged electrolyte
obtained almost exclusively from table salt
– Together with sodium helps in regulating fluid balance
– Aids in digesting food as part of stomach acid
– Assists white blood cells in mediating immune responses
– Only toxicity from high chloride intake is hypertension
(due to high Na+ from table salt)
– Deficiency is rare (severe dehydration or vomiting)

Question 19

Phosphorus role

Answer 19

major intracellular negatively charged electrolyte
– Most commonly found in the form of phosphate (PO4
3-)
– Works together with K+ to regulate fluid balance
– Plays a key role in bone formation
– Is important in the generation of energy from food (ATP)

Question 20

Phosphorus Toxicity & Deficiency

Answer 20

– High blood phosphorus levels can cause muscle spasms and
convulsions (people taking excess vitamin D, kidney failure)
– Phosphorus deficiency is rare (oversecretion of parathyroid
hormone, vitamin D deficiency)

soft drinks (coke have 60 g of phosphoric acid, antimicrobial actions)

Question 21

Antioxidant Minerals

Answer 21

– Selenium
– Manganese
– Copper
– Iron
– Zinc

Question 22

Selenium

role

Answer 22

• Most of the selenium in our body is contained in
amino acids
– Storage form = selenomethionine
– Active form = selenocysteine
– Is a key component of glutathione peroxidase
– Also plays a role in the production of thyroid hormones

Question 23

Selenium

toxicity

Answer 23

• Selenium Toxicity & Deficiency
– Supplementation can cause toxicity (brittle hair and nails,
skin rashes, GI upset, liver cirrhosis)
– Deficiency is rare but can cause Keshan (from province) disease = cardiomyopathy in absense of HTN or cv disease
– Deficiency can also lead to a form of cretinism (child has mental impairment

Question 24

Manganese, Copper, Iron & Zinc

Answer 24

• Manganese, copper and zinc are part of the
superoxide dismutase antioxidant enzyme
system
• Iron is a component of catalase

Question 25

Minerals Important in

Regulating Blood Health

Answer 25

Minerals important in maintaining healthy blood
include
– Iron
– Zinc
– Copper

Zinc
– plays a role in synthesizing the heme structure of
hemoglobin
• Copper
– is a key component of ceruloplasmin (key protein
involved in iron transport)

Question 26

Iron

Answer 26

• Iron is a major component of oxygen-carrying proteins
in blood and muscle
– 2/3rds of our body’s iron is found in hemoglobin
– Iron is also a key component of myoglobin
– Iron is also a key component of cytochromes
• Iron storage and recycling
– Our bodies contain little iron (500-1500 mg in men & 300-1000 mg in women), and we reuse about 85% of iron released from hemoglobin breakdown

Question 27

Iron absorption is affected by

Answer 27

– iron status
– stomach acid (frees up iron)
– amount of iron in the diet
– type of iron (heme iron in animals is more absorbable that nonheme iron in plants)
– other dietary factors present in food (e.g. polyphenols & phytates)

Iron toxicity and deficiency
– accidental iron overdose is the most common cause of poisoning
deaths in children <6 years of age in the USA
– iron supplements can cause GI upset
– iron must be avoided in people with hemochromatosis
– iron deficiency leads to anemia

Question 28

Zinc role

Answer 28

• Plays an important role in many body systems
– Enzymatic functions
– Structural functions (3D structure of proteins)
– Regulatory functions
• Zinc deficiency
– Is rare but may be seen in individuals who consume
predominantly grain-based foods
Ø Phytates and fiber inhibit zinc absorption
– May cause delayed sexual maturation, impaired
appetite, and increased incidence of infections

Question 29

Copper

Answer 29

• In addition to it’s role in the generation of
ceruloplasmin, copper also plays a role in the
synthesis of collagen and elastin
• Copper Deficiency
– Can lead to microcytic anemia
– Will cause symptoms similar to that seen with
hemochromatosis
• Copper Toxicity (Wilson’s disease)
– Can be treated with zinc supplements

Question 30

Calcium

Answer 30

• Major function of calcium is to provide structure to our
bones
– 99% of calcium in our body is stored in the hydroxyapatite
crystals built up on the collagen foundation of bone
– blood calcium is very tightly controlled (PTH & vitamin D)
– plays a role in the normal transmission of nerve impulses
– Assists in muscle contraction

Question 31

• Calcium toxicity and deficiency

Answer 31

– hypercalcemia (overproduction of PTH, cancer) can lead to fatigue, loss of appetite, constipation, and mental confusion
– hypocalcemia (vitamin D deficiency, disease impairing PTH production) can lead to muscle spasms and convulsions

Question 32

Magnesium

Answer 32

• Major function of calcium is to provide structure to our
bones
– Total body magnesium content is about 25 grams, and 50 – 60% of
that is in our bones
– Influences the formation of hydroxyapatite crystals through its
regulation of calcium balance (vitamin D, parathyroid hormone)
– Key cofactor for over 300 enzymes (e.g. ATPases)
– Plays an important role in DNA and protein synthesis and repair

Question 33

Magnesium toxicity and deficiency

Answer 33

– Pharmacological levels of magnesium cause diarrhea
– People with poor kidney function may be at risk for hypermagnesemia
– Deficiency can lead to muscle cramps, spasms, nausea, and weakness
– Long-term deficiency is associated with many chronic diseases (heart disease, hypertension, osteoporosis)

Question 34

Fluoride

Answer 34

• Major function of fluoride is to promote mineralization and protect against cavities
– 99% of our body’s fluoride is stored in our teeth and bones as fluorohydroxyapatite (more resistant to destruction by acids and bacteria)
– AI ranges from 1-4 mg/day
• Fluoride toxicity and deficiency
– Difficult to be deficient for fluoride due to fluoridated water and dental products
– Excess fluoride intake can cause fluorosis (stained and pitted teeth, doesn’t show problems with teeth fxn)
– Fluoride deficiency leads to cavities

Question 35

Iodine

Answer 35

• Iodine is required for the synthesis of thyroid hormones
– thyroid hormones are important for the regulation of body
temperature, basal metabolic rate, and growth
– iodine is found in high amounts in marine animals that
concentrate iodine from seawater (saltwater fish & shrimp)
– table salt often has added iodine (since 1924)
• Iodine toxicity and deficiency
– Deficiency leads to goiter
– Iodine deficiency during pregnancy
can cause cretinism*** (largest preventable brain condition)

Question 36

sulfur, chromium

Answer 36

• Sulfur
– Helps stabilize 3-dimensional shape of proteins
– Assists with detoxification of of alcohol and various drugs in the
liver
– No DRI since we get sulfur from amino acids
• Chromium
– Enhances insulin’s ability to promote glucose uptake into cells