Calcium Flashcards
mineral represent 4-5% of the body weight what is the break down
50% calcium, 25% phosphorus, 14 % remaining
mineral represent 4-5% of the body weight what is the break down
50% calcium, 25% phosphorus, 14 % remaining
minerals are absorbed in what state? except?
in ionic state, except heme iron it absorbed as part of heme complex
metals =
minerals with positive charge
nonmetals=
minerals with negative charge
amount of major minerals a day
> 100 mg/day
trace minerals per day
1-100mg/day
ultratrace
what are the major minerals
Ca, Cl, Mg, P, K, Na, S
what are the trace minerals
Fe, Zinc, Cu, F
ultratrace minerals
I, Se, Mn, Mo, Cr, As, B, Ni, Si
what is the most abundant divalent cation in the body
Calcium
what is the most comm form of calcium in supplements and fortified foods? what does it require to digest
Calcium carbonate, atleast 1 hour in an acidic enviromnet
what two types of calcium dont require an acid environment to digest
calcium citrate, calcium lactate
calcium is absorbed by what two methods?
active transport in SI using calbindin 9k
passive diffusi
minerals are absorbed in what state? except?
in ionic state, except heme iron it absorbed as part of heme complex
metals =
minerals with positive charge
nonmetals=
minerals with negative charge
amount of major minerals a day
> 100 mg/day
trace minerals per day
1-100mg/day
ultratrace
what are the major minerals
Ca, Cl, Mg, P, K, Na, S
what are the trace minerals
Fe, Zinc, Cu, F
ultratrace minerals
I, Se, Mn, Mo, Cr, As, B, Ni, Si
what is the most abundant divalent cation in the body
Calcium
what is the most comm form of calcium in supplements and fortified foods? what does it require to digest
Calcium carbonate, atleast 1 hour in an acidic enviromnet
what two types of calcium dont require an acid environment to digest
calcium citrate, calcium lactate
calcium is absorbed by what two methods?
active transport in SI using calbindin 9k (requires vit D)
passive diffusion in Si when calbindin 9k is saturated does not require vitamin D
with active and passive calcium absorption how much calcium can be absorbed?
500mg
when blood calcium is low what takes place to bring it up
- parathyroid hormone is secreted to induce hydroxylase in the kidney,2. hydroxylase activates calcitriol(vitamin D), 3. calcitriol stimulates synthesis of calcium-binding proteins 4. calcium binding proteins increase calcium absorption in SI (calbindin 9k) and decrease calcium excretion in kidneys (calbindin 28k)
what enhances ca absorption?
vitamin D, sugars, proteins
what increases Ca excretion
Na, protein, caffeine
what decrease Ca excretion
estrogen, potassium, phosphorus
what inhibits Ca absorption
Fiber, phytate, oxalate, divalent minerals (Zn, Mg, Cu), fatty acids
typical adult absorbs what percent of Ca
20-30%
RDA of Calcium
adults 19-50= 1000mg
adults >50=1200mg
Calcium sources
Dairy, fish, spinach, tofu, fortified grains
calcium functions
bone mineralization, cell signaling
other nutrients in bone calcification
vitamin A, D, K, c and B6
Ca is found with what other minerals in osteoblast
phosphorus, fluoride, magnesium, potassium, strontium, sodium,
what types of cell signaling is Ca involved in
muscle contraction, nerve conduction, blood clotting, enzyme regulation, membrane permeability
calcium deficiency results in?
tetany, paresthesia due to hyperecitability of nerves causing spontaneous discharge
Calcium toxicity causes? what is the tolerable upper limit of Ca
fatigue, hallucinations, constipation, kidney stones, calcium deposits in soft tissue
TUI= 2500mg a day can also occur with 2000mg a day and vit D
causes of calcium toxicity
high dairy or supplement intake, hyperparahyroidism, bone cancer, sacoidosis, turberculosis
which form is Ca absorbed in
calcium ion
what stimulates parathyroid hormone secretion (PTH)
low serum calcium
where is calbindin 28k located in vivo
kidneys
what is a clinical indicator of a calcium deficiency
tetany
what can blood calcium levels be used to diagnose
calcium toxicity
