chapter 14 - major minerals Flashcards
mineral
naturally occurring element that is:
1. inorganic (doesn’t contain carbon)
2. needed in SMALL amounts
3. essential
are minerals cofactors?
minerals are cofactors but NOT coenzymes (they don’t bind to enzymes)
“major” mineral meaning
you need 100 mg+ per day
- stored in body in larger amounts than trace minerals
major minerals list
- calcium
- chloride
- magnesium
- phosphorus
- potassium
- sodium
- sulfur
“trace” minerals meaning
you need less than 100 mg per day
trace minerals list
- selenium
- iodine
- zinc
- iron
grains minerals
- sodium chloride
- calcium (ONLY fortified grains)
- phosphorus
- magnesium
- iron
- zinc
- selenium
basically: everything EXCEPT sulfur, potassium, & iodine
veggies main minerals
- potassium
- magnesium
fruits minerals
- potassium
dairy main minerals
- calcium
- phosphorous
- zinc
protein main minerals
- sodium chloride (PROCESSED foods)
- potassium
- phosphorous
- magnesium
- selenium
- iron
- zinc
basically: everything EXCEPT calcium, iodine, & sulfur
mineral digestion
don’t require digestion because they’re in a “free” form
mineral absorption
small & large intestine: directly absorbed into blood stream
factors affecting mineral absorption
- physiological need (e.g. children absorb more iron because they’re growing)
- body’s stores (e.g. body absorbs less iron & calcium if it already has enough stored)
- bioavailability (the amount of a nutrient actually available to cells & tissues)
factors affecting mineral bioavailability
- interactions with vitamins & other minerals
- gastric acidity (more stomach acid increases minerals’ availability)
- plant chemicals binding
minerals’ bioavailability and plant chemicals
plant chemicals BIND to minerals, decreasing minerals’ bioavailability/absorption
phytic acid, oxalic acid, polyphenol
phytic acid (phytate)
plant chemical that binds to zinc & iron
comes from wheat
oxalic acid (oxalate)
plant chemical that binds to calcium
comes from green leafy plants
polyphenols (tannins)
plant chemical that binds to calcium & iron
comes from tea, dark chocolate, & wine
mineral transport
once in bloodstream, minerals are transported in free form OR are bound to proteins
mineral storage
amount that is actually stored varies WIDELY
e.g. LARGE amounts of calcium & phosphorus are stored in bones, SMALL amounts of iron are stored in liver & bone marrow
mineral excretion
most are excreted via urine
sodium main function
help absorb glucose & amino acids
sodium sources
salt = 40% sodium (Na+) and 60% Chloride (Cl)
mainly in processed foods
some occurs naturally (milk, chicken)
sodium recommended intake
AI = 1,500 mg/day
UL = 2,300 mg/day
97% of adults exceed sodium AI
excess sodium risks
risks:
hypertension –> heart disease & stroke
more calcium in urine –> kidney stones
potassium main function
regulate calcium excretion (in urine)
potassium sources
fruit & veg
low potassium risks
hypertension –> heart disease & stroke
can affect bone health
average intake = 2600 mg below recommended
sodium & potassium
do opposite things
sodium pushes calcium out of body, but potassium keeps it in the body
chloride sources
salt, some fruit & veg
chloride 2 main functions
- it’s part of HCI (stomach acid)
- immune function
systolic vs diastolic pressure
systolic:
max BP in an artery when ventricles CONTRACT
diastolic:
BP in an artery when ventricles RELAX (between contractions)
hypertension
persistently elevated BP
BP categories
normal = under 120/80
high = over 140/90
hypertension risk factors
- family history
- old age
- obesity
- physical inactivity
- excess sodium
- cigarette smoking
- excess alcohol
- type 2 diabetes
hypertension treatment
best way to lower BP = lose weight
also, increase potassium
DASH diet
for lowering blood pressure
low in sodium, fat, cholesterol
high in fruit, veg, low-fat dairy
calcium main functions
- develop & maintain bone
- blood clotting
- cell metabolism
bone-building cells
osteoblasts - produce collagen & add minerals
ostocytes - release bone minerals
bone-resorbing cells
osteoclasts - release acid & enzymes to dissolve bone
calcium sources
top source: tofu
then,
1. salmon
2. baked beans
3. fortified soy milk
calcium intake
RDA: 1,000 mg/day for everyone
things that increase calcium bioavailability
eat calcium-rich foods WITH other foods that have lactose, sugar, & protein
calcium absorption
absorbed in small & large intestines - usually 25-30% efficiency
decrease calcium absorption/bioavailability
- Vit D deficiency
- reduced HCI
- high fiber, phosphorus, & phytic + oxalic acid intake
- diarrhea
increase calcium absorption/bioavailability
- Vit D
- HCI
- lactose (in infants)
calcium & hormones
thyroid & parathyroid gland secrete hormones that regulate blood calcium
PTH
parathyroid hormone - secreted by parathyroid glands when blood calcium is low
makes calcitriol to increase calcium absorption
calcitriol
formed from PTH, INCREASES calcium absorption
calcitonin
released from thyroid gland, DECREASES calcium absorption, increases calcium excretion
hyperparathyroidism
causes persistently elevated blood calcium
PTH releases too much calcitriol –> too much calcium absorption
hypercalcemia
high blood calcium
caused by hyperparathyroidism
symptoms:
1. kidney stones
2. bone pain
3. muscle weakness & fatigue
4. hypertension
leads to kidney failure, decreases absorption of other minerals
phosphorus main functions
85% of phosphorous = found in bone
1. major component of bones & teeth
2. component of ATP (energy production & storage)
3. component of DNA, RNA, phospholipids, enzymes
phosphorus sources
animal products & legumes
magnesium unique functions
bone structure & mineralization via calcium metabolism
cofactor for 300+ enzymes that use ATP
DNA/RNA synthesis
magnesium sources
- legumes & nuts
- whole wheat products
- seafood
- dark green leafy veg
hypermagnesemia
high blood magnesium
occurs from too many laxatives, antacids, or supplements
UL = 350 mg/day (only from meds)
osteoporosis
chronic disease where bones have low mass & reduced structure
osteopenia
weak bones = susceptible to fracture
peak bone mass
bones have their maximum strength
ages 20-30, starts to decrease at ages 30-40
assess bone density
- fractures
- measurements of bone mineral density (DEXA, ultrasound)
- height loss (over 1.5 in)
osteoporosis risk factors
- female
- old
- white/Asian
- family history
- little estrogen or testosterone
- small frame
- low calcium & vit D
- steroids & antiseizure meds
- low physical activity
- smoking cigarettes
- excess alcohol/caffeine intake
osteoporosis prevention
enough calcium, vit D, phosphorous, magnesium, potassium, protein
do weight lifting
avoid smoking
hormone replacement therapy if needed
calcium additional benefits
reduced risk of:
1. colon cancer
2. kidney stones
3. blood pressure
poor bone health symptoms
- fractures
- loss of height
calcium supplements
ONLY for people who can’t get enough calcium from their diet
increase absorption by taking in doses of >500mg just before/after meals
calcium supplement adverse effects
bloating/constipation
coronary artery calcification
major minerals that do nerve transmission
- Sodium
- Potassium
- Calcium
- Magnesium
major minerals that do muscle contraction
- sodium
- calcium
major minerals that regulate BP
- potassium
- magnesium
major minerals that do acid-base balance
- chloride
- phosphorous
hypernatremia
excess sodium in blood (sign of dehydration)
different from hyponatremia (not enough sodium in the blood)
