chapter 8: Minerals Flashcards
defining features of minerals
they are indestructible
they come from the earth, we cannot create them in a lab
no living organism can synthesize them
how many many minerals (and which types) do we require in our diet?
7 major minerals
8 trace minerals
25% if the elements found on earth are required by the human bidy
–> the bulk of these ere minerals
how much minerals do we require per day of each type?
Major minerals: over 100mg per day
Trace minerals: less than 100 mg per day
–> this does nit mean they are not important, they are just less abundant
which minerals combine to form our skeleton’
calcium and phosphorus
the most abundant trace mineral
Iron
intracellular fluid
fluid within cells
usually high in potassium and phosphate
accounts for approximately two thirds of the body’s water
interstitial fluid
fluid between the cells (intercellular)
usually high in sodium and chloride
large component of intracellular fluid
intravascular fluid
located within the cardiovascular system or lymphatic system
our principle source of minerals
food
what does “hard water” contain?
calcium and magnesium
the more minerals there are in water, the “harder it is”
–> can smell and taste unpleasant
what does “soft water” contain?
it is treated with sodium or potassium
downside to soft water
being high in sodium, can increase hypertension
–> hard water could reduce it
the final source of minerals
dietary supplemtens
–> it is easy to consume a toxic amount
what does the bio availability of minerals depend on?
our physiological needs
–> depends on age, gender, diet, and pregnancy status
the source of the minerals is also important
–> for some, it is more bio available in animal based foods, while other in plants
the combination of the foods we ate can affect the bioavailability of our minerals
the presence of other minerals can affect mineral bioavailability
–> the can often compete with each other for absorption
binding factors and minerals
the bind minerals together
–> it prevents their absorption
the most common mineral element in the body
calcium
proportion of calcium found in bones and teeth
more than 99%
what does calcium do?
maintains the structural integrity of bones
–> calcium in bones acts as a reservoirs for when blood calcium levels drop
what do neurons rely on to be able to communicate with other neurons?
they rely on blood calcium
–> found in extracellular fluid compartments in ionic form
–> this ionic form is blood calcium
synaptic cleft
the space between the presynaptic and postsynaptic cells
how is blood calcium crucial for neuron communication?
- electric signals open protein channels for calcium to flood into the presynaptic neuron
- once inside, it allows the neurotransmitters to spill into the synaptic cleft
–> without calcium, the neurotransmitters are not released
- an electrical signal is generated and it runs down to the next neuron
what are convulsions a sign of?
a sign of depleted blood calcium levels
osteoclasts cells
the specialized cells in bones that break down bone tissue to release calcium
osteoblasts cells
the specialized bone cells that build bone tissue
how does bone calcium leave bones to go to blood calcium when the latter’s levels drop’
bone is demineralized to liberate calcium into blood
who build bones and have very active osteoblasts cells?
children
who simply repair damage to existing bones?
adults
–> as we age, the activity of osteoblasts cells declines
why do we lose bones when we age?
as we age, the activity of osteoblasts (building of bones) cells declines
osteoclasts (degrading of bone tissue) cells still function properly tho
what maintains calcium homeostasis? how?
the thyroid and parathyroid glands
–> they regulate the activity of osteoclasts cells and osteoblasts cells
anatomy of a thyroid gland
is is butterfly shaped
wraps itself around the trachea
it is intimately associated with blood vessels
the parathyroid glands (4 of them) are behind it
role the parathyroid glands with the thyroid gland?
they synthesize the hormones released by the thyroid gland into the blood
calcium homeostasis
equal levels of osteoclasts cells and osteoblasts cells activity
the process of stabilizing the falling blood calcium levels
- parathyroid glands secrete PTH
- PTH stimulates activation of vitamin D in kidneys
- the PTH and Vitamin D work together to decrease the amount of urine excreted in urine
- Vitamin D travels to small intestine and increases the bioavailability of calcium
–> this makes the blood calcium levels rise immediately
- the PTH and Vitamin D work together to stimulate osteoclasts to break down bone
rising calcium levels are only a concern for whom?
for children
why is the best source of calcium dairy?
it has the highest amount of calcium per serving and relatively high bioavailability
a single serving of milk provides 96 mg of calcium
the faith of calcium is determined by what?
determined by the work of the parathyroid glands
–> the orchestrate how much is absorbed, circulated, deposited, and eliminated
which other nutrient can alter and mess up calcium homeostasis?
how?
sodium
excess salt intakes forces the kidneys to increase urine production in an effort to eliminate excess sodium
–> this makes us lose calcium as well
peak bone mass
the highest attainable bone density achieved in the first 3 decades of an individual’s life
the period in our life in which we achieved the greatest amount of bone
regardless of gender, when does bone density begin to drop?
after the age of 30
why do women lose even more bone mass after menopause?
because estrogen is a hormone that decreases osteoclast activity
after menopause, there is no more estrogen, which increases even more the osteoclast activity
osteoporosis
a disease in which bones become fragile
there can be easy fractures too
shrinking in height is a clear sign
–> happens to a collapse of the vertebrae (which can cause extreme pain)
happens mostly of woman
best way to minimize the risk of osteoporosis
- maximize peak bone mass in early adulthood
- resistance exercise well into older age
- meet the RDA for calcium
–> helps maintain blood calcium levels and keep bones dense
after decades of low calcium intake, osteoporosis becomes more likely
how much of phosphorus is stored in bones (proportionally)?
where is the rest found?
85% stored in bones
the remaining 15% is found in the intracellular fluid compartment
is it easy to get phosphorus deficient? why?
no bruv
because it is in nearly everything we eat
what is the link between phosphorus and tooth decay.?
too much of an increase in phosphorus intake (with soft drinks for example) and lack of calcium intake will cause teeth to decay
proportion of magnesium found in bones?
where is the rest found?
more than 50%
the rest is found inside of cells
role of magnesium
influences the formation of hydroxyapatite crystals
is also an important intracellular ion
–> is found inside of cells
what is magnesium in plants associated with?
in the green pigment chlorophyll
–> any deep green leafy vegetable is a good source of magnesium
–> legumes too
where does our body get its magnesium we fail to meet our required RDA for this mineral or we just don’t take enough?
our body will take it from our bones
what is the mix (compound) that makes table salt?
where can both these minerals be found in our body?
sodium chloride
in the extracellular fluid compartments
what is sodium crucial for?
crucial in fluid balance and nerve impulse transmission
importance of chloride in our body
also plays a role in the fluid balance
more importantly, become part of the stomach’s hydrochloric acid
how do we get table salt?
mined from inland salt deposits from old seas
cheap
how do we get fleur de sel?
harvested from artificial salt ponds by evaporation
more expense
where is most sodium in the body found?
in the intravascular and interstitial compartments
role of sodium in neuron transmission?
after calcium did its whole thang, sodium binds to the electrons once they reach the post synaptic cell
unlike calcium (electrical stimulus), this is a chemical stimulus
the more sodium we consume, the more or less extracellular volume compartment?
what does it do if we have too much?
the more volume
the enlarged extracellular volume compartment presses additional pressure on our arteries
–> with time, these arteries stiffen
–> can make the heart get beef as hell, but we don’t want that because it can lead to heart failure
high sodium is associated with hypertension
how are children increasingly affected with hypertension
hypertension
because most people exceed the UL for sodium by several hundred mg every day
hypertension
higher than normal blood pressure
primary hypertension
hypertension that develops without an identifiable cause
secondary hypertension
hypertension that is caused by a specific disorder such as kidney disease
the tolerable UL for sodium
2,300 mg per day
the AI (adequate intake) for sodium
1,500 mg per day
the treatment to reduce hypertension?
lowering sodium intake
also, increasing potassium intake with foods naturally containing it
where do we find 95% of the body’s potassium?
inside cells
why do processed foods no longer have potassium?
because of their processing
what is potassium intake associated with?
associated with lowering blood pressure
the most abundant trace mineral in the body
iron
proportion of iron in red blood cells
over 60%
how many red blood cells do we produce every day
2 billion every day
how many hemoglobin molecules in one red blood cell
280,000,000
hemoglobin and iron
each hemoglobin molecule is studded with four heme compounds that bind with iron
–> iron binds to the oxygen that we inhale
what happens if we don’t have Iron?
without Iron, oxygen has nowhere to bind
–> too little Iron is deadly
if too little Iron is deadly, what about too much iron?
just as deadly
leading cause of accidental poisoning in young children?
over ingestion of iron
why is too much iron just as deadly as too little?
because in either way, it will enter the blood capillaries
if too little is consumed, ferritin will almost not be produced at all, which will let iron escape in the blood capillaries
If we consume too much, more ferritin will be produced to bind to the iron, but since epithelial cells only have a lifespan of 3 days, they will die and will carry Iron with them in the binded ferritin and iron to be excreted (rendering it useless)
ferritin
the iron storage protein
binds to iron
what is the proportion of Iron our body can absorb (depending of our Iron status)
between 5% and 40%
what does the bioavailability of iron depend on?
on our body’s physiological need for it
also depends on the source of Iron
where do we get our heme iron?
why they contain heme?
from animal flesh
because animals got blood, so they got heme
where do we get our non-heme iron?
why do they not contain heme?
plants
because plants don’t have blood
–> contain compounds that reduce the bioavailability of iron
proportion of iron intake coming from plants
90%
the most common nutrient deficiency
iron deficiency
iron-deficient anemia
sever depletion of iron stores that results in a low hemoglobin concentration
–> red blood cells are small and paler
one has to work harder to circulate oxygen poor blood throughout the body
–> the heart is overworked
–> over time, the heart enlarges and gets beef and eventually leads to heart failure
high risk groups for iron deficiency
women (with periods)
pregnant women
growing infants
children
teens
how much iron do we lose when donating 0.5L of blood?
we lose 2.5 mg of iron
–> it takes the body several months to replace the iron
where do almost all iodine end up upon absorption?
in the thyroid gland
iodine’s function
synthesis of thyroid hormones
role of thyroid hormones
regulate body temperature and metabolism
the world’s major source of iodine
the ocean
iodine is also found in rich supply in soils that were once submerged in ancient seas
Goiter
a deficiency cause by a deficiency in iodine
enlarged thyroid gland
–> hoping to catch iodine that is simply not there
cretinism
a deficiency cause by a deficiency in iodine
impaired fetal development
stunted growth
physical and mental abnormalities
the leading cause of mental impairment globally
Iodine deficiency
amount of people suffering from Iodine deficiency
2 billion
which contains iodine
table salt or fleur de sel
table salt
the hormone that allows glucose to enter into cells
insulin
what does chromium do
enhances the ability of insulin to take in glucose into our cells
importance of zinc
it does it all (it is a versatile mineral):
energy metabolism
amino acid metabolism
DNA metabolism
antioxidant function
heme synthesis
growth and development
how many enzymes require zinc?
mare than 100
metalloenzymes
enzymes that bond to minerals
they contain one or more minerals as part of their structure
–> these minerals are called cofactors
effects of a zinc deficiency
severe growth and development impairment
increases risk of infection
three main minerals that work as anti oxioxidants
zinc
–> decreases copper absorption
copper
selenium (most powerful one)
selenium
a powerful antioxidant
can protect against some form of cancer
what can our intake of selenium be dependent on?
it can depend on our geographical location, which influences soil content of selenium
increasing our intake of brazil nuts will increase which mineral intake?
selenium
fluoride
makes teeth far more resistant to decay
is present in water (but varies in quantity depending where we are)
proportion of children with at least one dental carie
60%
fluorosis
it messes up teeth
effect of fluoride toxicity
minerals affecting energy metabolism
iodine
zinc
chromium
iron
minerals affecting blood health
zinc
iron
calcium
minerals affecting growth and development
zinc
calcium
iodine
minerals affecting amino acid metabolism
zinc
minerals being anti oxidants
zinc
copper
selenium
minerals affecting DNA metabolism
zinc
minerals affecting bone health
calcium
phosphorus
magnesium
fluoride
minerals affecting fluid balance
sodium
potassium
magnesium
minerals affecting nerve impulse transmission
calcium
sodium
potassium
