Exam - Iodine Flashcards
(40 cards)
supplement label of iodine
thyroid gland support
is iodine prevalent in most foods
no, iodine content is low
what is iodine
inorganic mineral that is highly water soluble
where is iodine found in higher concentrations
in coastal populations opposed to mountainous regions
what kind of food has high iodine concentration
seafood - especially sea greens
where does most iodine consumed come from in North America
salt fortified with potassium iodine
how many mg of iodine does iodized salt contain per g of salt
0.03
as of 2007, what percentage of the world population live in areas of iodine deficiency
29%
how can dietary iodine be found
bound to amino acids or free
what occurs to iodine in our GI tract
iodine is rapidly converted to iodide (ionic form) and absorbed
where does iodine get absorbed
mostly in stomach, a bit in small intestine
what does free iodide do in blood
circulates and can enter all tissues
where does most of free iodide accumulate
thyroid gland
what percentage of the iodine in our body is located in the thyroid gland
70-80%
what is the uptake of iodide mediated by
active transport system: Na+/I- symporter (NIS)
do all tissues depend on iodine
no, all tissues depend on thyroid hormones T3 and T4 rather than iodine itself
what happens to T3 and T4 after they are made
they are released into blood and transported by carrier proteins
is there more T4 or T3 in blood
50x more T4 than T3 in blood - but T3 is 100x more potent
what does T3 interact with
thyroid hormone receptor
what is T3 and T4 production regulated by
thyroid stimulating hormone
what occurs when T3 levels are low
the hypothalamus signals to the pituitary to release TSH
what is thyroglobulin (THG)
tyrosine-rich protein
what do thyroid hormones influence
how body stores and uses energy
things that thyroid hormones control
- breathing
- heart function
- nervous system function
- body temp
- cholesterol level
- energy balance
- brain development
- skin moisture
- menstruation
