minerals e lecture Flashcards
why are minerals important
for correct physiological function
when can mineral deficiency occur
when crops grow on poor soil
which minerals are macrominerals
calcium magnesium phosphorus sodium potassium chlorine sulpher
what is the rni for macrominerals
greater than 100mg/day
which mineral is the most abundant in humans
calocum
how much calcium is present in a 70 kg man
1.2kg- 99% is found in the skeleton
what is the recommended nutrient index for calcium
700mg/day
when is calcium intake higher
during pregnancy
lactation
post menopause
what are sources of calcium
dairy and fortified foods such as bread and orange juice
how much calcium is taken from the diet
around 15-45%
why is calcium from spinach poorly absorbed
due to the complex formation with oxalic acid
why is calcium absorption in beans and cereals inhibited
by phytate
how is calcium absorption increased
by the parathyroid hormone and active vitamin D
what is the function of calcium
structural in skeleton and as an intracellular second messenger in (cAMP)
transmission at the synapsed and in muscle contraction and blood clotting
why might we be deficient in calcium
calcium deficient diet
secondary vit d deficiency
malabsorption
what is ostemalacia caused by
secondary deficiency in vit d
what oral problems are there if you have vitamin d deficiency
incomplete mineralisation of teeth
increased caries risk
malformation
increased perio problems
which group have the highest risk of gingival detachment in a low ca diet
less than 500mg/day
what is xs calcium caused by
hyperthyroidism
which issues can the deposition of calcium salts cause
renal stones and calcified arteries
arrhythmias, weakness, anorexia, constipation, sluggish nervous response.
what is the rni for phosphorus
550mg/day
what are the sources for phosphorus
most food
how is phosphorus absorbed
50-70% in diet(enhanced by vitamin D
what is the function of phosphorus
With Ca in mineralised tissues, biological buffer, and many biomolecules and processes
which biomolecules is phosphorus found in
ATP
DNA
RNA
why might people suffer with a phosphorus deficiency
usually due to kidney misfunction, aluminium in antacids, total starvation
what can phosphorus deficiency lead to
osteomalacia
rickets
what is osteomalcia in children called
rickets
what can excess phosphorus cause
Disturbance of calcium balance, increased porosity of the skeleton
which elements are known as trace elements
iron zinc copper cobalt iodine chromium manganese selenium Molybdenum nickel silicon vanadium
how much iron is lost per day via the GI tract
1MG/day
how much iron do adult males require
1mg/day
how much iron does a child require
1mg/day
how much iron does a menstruating women need
2mg/day
how much iron is found in 1ml of blood
0.5mg
how much iron does a pregnant women need
3mg/day
what is the rni of iron for women
14.8mg/day
what is the rni of iron for men
8.7mg/day
why is the rni of iron so much higher than how much is needed
as the absorption of iron is poor
what are two forms of dietary iron
haem iron
non haem iron
where is haem iron found
from meat liver - from haemoglobin and myoglobin
where is non haem iron found
green veg and cereals
this is slowly absopred
tannin in tea
which minerals can inhibit non haem iron takeup
calcium, polyphenols, phytates (found in legumes and whole grains), oxalate (green leafy veg)
how can we get iron deficiency
Inadequate dietary intake, blood loss leading to anaemia
what is the function of iron
In many proteins and enzymes – oxygen transport proteins, electron transport proteins etc.
how is iron transported in the body
bound to transferrin
how is iron stored in the body
it is stored bound to ferritin bone marrow and spleen in the haemosiderin in liver
how are iron levels controlled
by absoprtion
how can people suffer from iron toxicity
excess dietary intake or genetic disease
how much iodine do we need in a day
140 microgramms/day
where is iodine found
sea food, dairy products (table salt in US).
what is the function of iodine
synthesis of thyroid hormones by thyroid gland – control metabolic rate –also essential for brain development in early life.
what can deficiency of iodine cause
reduced synthesis of thyroid hormones – goitre in children and adults and mental retardation (cretinism) in neonates.
What is the recommenced RNI for iodine
140 micrograms per day
How are thyroid hormones stimulated
The hypothalamus released thyroid releasing hormones to the anterior pituitary and the anterior pituitary releases thyroid stimulating hormone which needs iodine and selenium for activation to produce thyroid hormones
What hormone does the hypothalamus release for thyroid hormone production
Thyroid releasing hero,one
What hormone does the anterior pituitary release to produce thyroid hormones
Thyroid stimulating hormone
What are sodium and potassium known as
Cationic electrolytes
What is the recommenced nutrient index of sodium
1.6 grams per day
What is the recommenced nutrient index of potassium per day
3.t grams per day
Where does most of the sodium in our diet come from
Added salt
What is the function of sodium
Sodium potassium pump
Controls ECF volume
Neuromuscular transmission
What is the function of potassium
Main action in fluid
Neuromuscular transmission
Rental acid base control
How much potassium cation is found in intracellular fluid
3.5-5milli Moles in plasma
What is chloride known as
An anionic electrolyte
What is the recommenced nutrient index of chloride
2.5mg per day but we exceed this because of salt in the diet
What are sources of chloride
Meat
Eggs
Salt
Sea food
Why might we suffer from sodium deficiency
Vomiting diarrhoea
Diuretics
Rental problems
Water loss and decreased plasma volume circulatory failure and collapse
Why do we have potassium deficiency
Vomiting diarrhoea
Diuretics
Steroid use
Renal issues
What does potassium deficiency cause
Arrhythmias and neuromuscular weakness
What happens if we have XS sodium in the Body
It occurs in hypertension in sensitive individuals
What issues can we suffer from with XS potassium
Hyperkalemia
What is the recommended intake for copper
1.2 mg per day
What are sources of copper
Liver
Shell fish
Nuts
Legumes
What is the function of copper
Used as a cofactors for many enzymes
Antioxidant
Enzymes associated with melanin production
Proteins associated with iron absorption
Which cofactors is copper used in
Cytochrome oxidase
Lysyl oxidase
What are the symptoms of copper deficiency
Tissue fragility Fragile bones Ruptured aorta Diminished skin pigment Neurological disorders
What is Wilson’s disease
A rare genetic disorder which impairs copper excretion in bile
Copper accumulates in the brain and liver causing severe damage
Kayser fleischer rings in eyes
What is the RNI of magnesium
270mg per day
What is the function of Mg
Bone biology and co factor Also involved in blood clotting Activation of vitamin D And RNA and DNA function Nerve transmission and muscle contraction
Which group of people can be deficient in magnesium
Alcoholics
What does Mg deficiency cause
Neuromuscular spasms Arrhythmias Increased heart rate Bone fragility Gingival problems
What is the RNI of zinc
10mg per day
What is the function of zinc
Cofactors in many enzymes- in protein synthesis
Also forms zinc fingers which are structures of TF that interact with DNA and regulate gene expression
What are zinc fingers
zinc fingers which are structures of TF that interact with DNA and regulate gene expression
What does deficiency of zinc cause
Decreased protein and dna synthesis Retarding growth
Delays wound healing and compromises immunity
Impaired the senses of taste and smell
What is the RNI of chromium
Not sure but 30 micrograms has been set in the US
What are the sources of chromium
Whole grains Seafood Cheese Chicken Meat
What is the function of chromium
Improves insulin function by increasing insulin binding to cells
Insulin receptor number and phosphorylation of the Insulin receptor
What do diets high in simple sugars cause to happen with chromium
Increased urinary chromium excretion
Which people might suffer chromium deficiency
Those who only eat processed foods or take IV nUtrition
