Question about what T3 is: I have a question that... - Thyroid UK

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Question about what T3 is

Raucous profile image
7 Replies

I have a question that I'm hoping someone here may know the answer to - just curiosity really. Does FreeT3 represent the T3 that under normal circumstances your thyroid would have produced or T3 that has been converted from T4 and is as yet unused by the cells?

The reason I ask is that one of the arguments I read in favour of NDT is that the body was not designed to live by conversion alone and that is why we need T3 as well, so it just got me wondering about test results.

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Raucous
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shaws profile image
shawsAdministrator

There is an explanation on the following link about FT3.

thyroiduk.org.uk/tuk/testin...

Before blood tests and levothyroxine were introduced everyone was given NDT due to their clinical symptoms, which all doctors knew at that time. Levothyroxine as you know is T4 alone, the inactive hormone. Some people cannot convert it for some reason into T3 (the only Active hormone needed in all our receptor cells) . New research by several Research Depts. (one of the doctors is an Adviser to TUK) that some need T3 added to T4. Whereas the BTA and it's guidelines insist that levo alone is 'perfect' - but it isn't for most on this forum. I didn't improve on levo, in fact I felt worse than having a TSH of 100, so thanks to TUK and trying most of the alternatives, it is T3 only which gave me back my life.

Many members try alternatives to levo but sometimes we have to try several to find one that suits us as individuals.

humanbean profile image
humanbean

At any one time there are two kinds of T3 in the body. There is bound T3 which is normal T3 attached to proteins which allow the body to move it around to where it is needed. There is unbound (i.e. Free) T3 which is the active form of T3 and which is available for instant use by the body. There is a Total T3 which is a total of Free T3 and bound T3.

humanbean profile image
humanbean in reply to humanbean

Posted too soon, sorry...

There are two sources of T3 in the body.

There is the T3 which is produced by the thyroid, and there is the T3 which is created by converting T4 in the body to T3.

Raucous profile image
Raucous

Thank you for your replies - so (to me at least it makes sense that, if in normal circumstances your body produces T3 as well as converting it from T4 when needed, then to expect it to manage by only converting it may be too much to ask. Especially if as time goes by the thyroid is becoming less and less effective at producing anything.

When I was first diagnosed I was told that I would need to be on Levo for life because once you start taking it your thyroid stops producing anything - do any of you have information about that?

One of my reasons for trying to get this really clear in my head is that I am very concerned about my 80yr old mother's health, she has been on Levo for many years (20-30 perhaps), she has also been on statins for a long time, she has osteoporosis and a lots of pains and muscles aches which I believe are due to statins, and her cholesterol is still slightly raised, which I think is because her thyroid is under treated. I would like her to come off the statins (there were no other risk factors other than cholesterol) but I need to be able to clearly explain things to her since she is reluctant not to do exactly as the doctors say.

Angel_of_the_North profile image
Angel_of_the_North in reply to Raucous

Statins are more of a risk for her than high cholesterol at her age. No study has ever shown that statins increase lfe span for elderly women. In fact, for the elderly, the higher your cholesterol, the longer you live according to the statistcs. However statins can dampen down inflammation. Read all of Dr Malcolm Kendrick's blogs (it'll take you a few weeks) and then decide. drmalcolmkendrick.org.

Raucous profile image
Raucous in reply to Angel_of_the_North

Yes I quite agree, especially as I think she is suffering from a host of statin related side effects, but both GPs & specialist she sees are still trying to get her cholesterol down. In the last blood test it had gone up (only just over the range) but a couple of months ago the GP has reduced her Levo because her TSH was at bottom of range (!angry face!) and I said that is probably why her cholesterol went up but why can't the specialists see that!

Ive already some of Malcolm Kendrick's stuff and am printing out some for her and I also have the Cholesterol con book.

Raucous profile image
Raucous in reply to Angel_of_the_North

Took loads of info to my Mum at weekend and said I thought she should say she wants to come off the statins for several months to see if symptoms improve - but couldn't believe it when my Dad then said he was now taking statins when I asked what his cholesterol was the report said 5.1!!!

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