Minerals Flashcards
(141 cards)
What are minerals
inorganic elects that originate from the earth and cannot be made by living organisms
for humans to absorb and use minerals they must first be
bound to organic compounds (containing carbon)
Where do plants obtain minerals from
earth
What percentage of body weight do minerals represent
4-5%
What are the two main minerals that make up 75% of the total
calcium and phosphorus
List the macro minerals
Calcium
Phosphorus
Magnesium
Sodium
Potassium
Chloride
Sulphur
List the Trace minerals
Iron
Zinc
Iodine
Selenium
Manganese
Molybdenum
Copper
Chromium
Boron
Fluoride
Silicon
Provide examples of how minerals exist as components of organic compounds
Phosophoproteins
Phospholipids
Metalloenzymes
Metalloproteins
In what state do macro mineral exist in the body
as cations (mg, Na,Ca,)
or anions (Cl, S, P)
Where are minerals absorbed and how
in the GIT, mainly the SI in ionic state (except iron)
Must be unbound from the organic compound with help of digestive secretions.
What happens to unabsorbed minerals
excreted in faeces
List the 5 key functions of minerals
Immune support
Thyroid health
Components of enzymes
Nerve and muscle function
Building tissues
What affects the bioavailability of minerals
Mineral status in the body (it up and down regulates)
Substances present in food, e.g. ascorbic acid and Fe ENHANCES; phytates and Fe INHIBITS
Other minerals present can compete for absorption. e.g. iron supplements reduce Zn absorption
Mineral supplements are rarely pure, they are bound to carrier molecules called
ligands
What are the common mineral carriers called (organic and inorganic)
Organic: citrate, ascorbate, gluconate, glycerinate
Inorganic: oxide, carbonate, sulphide, chloride
How are calcium levels regulated
PTH
Vit D
Calcitonin
List food sources of calcium
Dark green and cruciferous veg (most bioavailable; 2x dairy)
Nuts and seeds (sesame)
Beans
Herbs and spices (sage, coriander)
Sardines
List 5 functions of calcium
- Bone health: build and preserve bone mass (binds to collagen framework, increasing bone density)
- Cell signalling: influences transport of ions across membranes of organelles.
Nerve impulses
Regulates cardiac muscle function and vasoconstriction - Muscle contraction: required for binding of actin and myosin fibres
- Blood clotting
- Neurotransmitters: required for conversion of tryptophan to serotonin
List therapeutic uses of calcium
Osteoporosis, fracture repair
Blood pressure, muscle cramps and spasms, confusion, memory loss
Leg cramps in pregnancy
Bleeding disorders
Mood related PMS
How and where is calcium absorbed
SI, especially duodenum
Active absorption - controlled by vit D
Passive absorption - when Ca consumed
How much Calcium is not absorbed
50-70% in faeces
What inhibits the absorption of calcium
Low vit D
low stomach acid
high intake of phytates/oxolates
other minerals
GI dysfunction
What increases excretion of calcium
Menopause (low oestrogen)
High animal protein (high sulphuric acid and urea)
High salt diet
Caffeine
Some meds
Why is there a link between high diary intake and osteoporosis
it’s high in sulphur-based amino acids which can increase sulphuric acid formation, leaching Ca from bones