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667016 tn?1238895504

T4/T3 Conversion problems & T3 resistance........

I've done research on both of these - as I've got a T4/T3 conversion problem at cellular level, caused by micronutrient imbalances & estrogen dominance. The information I've read is pretty in depth & complicated. I still can't quite get my head around T3 resistance, the more I research - the more confused I get!  Is having a conversion problem & being T3 resistant the same thing?

Rach  : )  
31 Responses
667016 tn?1238895504

393685 tn?1425816122
I read over this a couple of times and just wasn't sure how to respond. I wasn't trying to ignore your question - jsut confused too.

Please do not take this as solid information -

I think they are different. T3 resistance - I think is your body resisting the conversion off T4 - like it doesn't like it. Maybe is taking it in - but rejecting?

The conversion issue is the actual T4 homone not converting over the T3, so there may be limited T3 actually being processed.

It does sound complicated and I think it is pretty controversial too. I think may people here with alot of research information passed by this question and feels they too may be unsure.

Hopefully someone can get this stuff down on lemans terms for all of us to understand.
667016 tn?1238895504
Thankyou for your response, much appreciated : )

Yep, your interpretation is similar to mine. From what my Dr told me, my conversion problem is (hopefully) only a temporary thing - just got to fix the imbalances & take supp's that promote a healthy conversion. Added to that, I'm on T3 for the time being - as T4 & NTH just don't work well with me.

I read somewhere that T3 resistance has something to do with 'mutant genes' & theres' about 100 different types. Fascinating, but very in depth reading. Anybody else done much reading on this?

Rach  : )
Avatar universal
Conversion of T4 to T3 can also be due to the fact that you have a lot of acid in your stomach which breaks down the T4, isnt absorbed properly and  is expelled via the bowel instead of being absorbed into the blood stream.
It can also be because you are not waiting at least an hour before eating after taking T4 med or waiting 4 hours before taking vitamins.
It is a complicated issue and I found at one stage I was the same.
My T4 was high and my T3 doing nothing.
So I waited and waited and waited .........and it finally got its act together lol.
Give yourself some time and if no good then get checked again.
Let us know how you go.
219241 tn?1413541365
You know the more I see people with TT's having problems with the T4/T3 conversion the more I am convinced I am seeing a pattern here. I see that too many of us are being treated as if we still have our thyroids. The thyroid normally converts the T4 into T3, but if we don't have that physical action, then no wonder we don't cope!
   I still believe that the medical profession is about 60 years behind the research...and unfortunately we have to suffer!
My T4 is always super high...therefore I HAVE the dose in my body..but why, I ask my endo.....?  Oh come back in 4 months after staying on the lower dose...but Doc...each time I lower the dose my T4 is still high.....Oh? Well, stay on the lower dose and come back in 4 months.....................Get my point? They don't know!
To me it is simple..GIVE the patient a bit of T3 after TT and I bet we get better..but as you know being a fellow Aussie, finding a doc here that understands that is almost impossible.
  Sometimes, everybody looks for the complex without realising the simple...I think I see the simple..you had a TT I had a TT many of us who complain about the T4/T3 have had TT's.....to me it is simple..No thyroid, no conversion...But tell the docs that? They look at me like I have 5 heads! But I will keep pushing this issue.
  Hope you aren't as hot as me down south!
393685 tn?1425816122
Actually 60 years ago - there were other things brought on the table that seemed to give some patients better treatment options.

Doctor had to listen to the patients then more than depend on labs as much as they do now.

TT's were more common then - RAI is used so much now for Hyperthyroidism/Graves which leaves a patient with a "thought" of what's really left producing with the thyroid.

So putting that into the shuffle - with an unclear knowledge of NOT knowing where you are at and possibly not converting properly. It's a shot in the dark daily for some to feel well.

I read alot on symptoms and conversion theories. Everyone has there opinion on it. Patients - doctors - and whom ever else. I believe as you say Red - I think there are many out there with this conversion question and maybe assisting with T3 could be good.

I am still trying to figure out that question you bring up about why T4 "convert" to begin with - when there is no gland. I brought that question up to my Chief of Endo in Madision last Monday and she simply said T3 would be fine with patients that have no thyroid, BUT it is a short lived medication ( Hormone) and it would be tasky to have to administer it through periods of the day to maintain properly.

She also added that if a missed dosage was done on that T3 med - the patient WOULD FEEL it pretty bad within 4 hrs without the T4 in your system already slowly converting.

SO - I believe her - she is a traditional endo as many have here. She is skilled and does not prescribe T3 or Armour - but open when someone can come to her as I did and speak about my history and illness.

ALSO FOR THE RECORD - You don't want to jump on the band wagon and go get T3 soley either - or for that matter Armour.

Armour "may" slow a sluggish thyroid into not wanting to produce on it's own when it is administered to a "regular" hypothyroid patient.  Armour treatment should be watched closely - and I believe T3 should be included.

590177 tn?1288429454
Redheadaussie I'm with you on this one!  Docs treat us like we have a thyroid and I always have to remind them... helloooo? I have no thyroid!!

Are you taking only T4?

I think conversion issues are worse when you don't have a thyroid. Also, you need proper minerals like zinc and selenium, and a whole lot of other vitamins and hormones need to be balanced too.....ferritin, dhea, adrenals etc etc etc list goes on...

393685 tn?1425816122
Actually I have read that the acid in the stomach is depleted in many thyroid patients - but more potent. Many have a DX of acid reflex and given meds to even lower the acid more - but it is not PH balanced and that is why thyroid meds may deplete or irritate a belly.

I suffered soooo much with acid for years- I could of went broke on the purple pill and everytime I tried going on it - it made me feel even worse. It cut the acid burning - but my digestive system was taking a beating from it too - it is a wonder I still have a gut left - or throat for that matter. I increased my digestive enzymes and looked into PH balancing and I no longer have any belly issues. I do believe getting my digestive system back on track helped me tremendously to balance out my thyroid levels.

Avatar universal
Everyone is asking HOW T4 converts when there is no thyroid.
To put it in laymans terms....I will give an example.
When you consume alcohol, the body and cellular sytem CONVERTS this alcohol into Ethanol (a pure form of alcohol). It starts off in the stomach then the acid in the stomach then takes it into the bloodstream and converts it.
How I dont know but I do know that after alcohol is consumed....within hours that alcohol has converted into Ethanol.

The same as Paracetomol and any other drug or medication....the body breaks it down.
So in hindsight, it isnt the thyroid that converts the T$ into T3...it is the body itself.

I was told a few weeks ago by a top Professor that acid does play a big part in breaking down medications in the body before it has time to absorb.

Food for thought.....
393685 tn?1425816122
I do see that conversion being right Deb -

On the other hand the meds are based as an iodine sodium - so if a person still has a thyroid - part of that should be absorbed there too. - At least that is my thought along with the liver processing it too.

When there is no thyroid left to pull in that medication - then I think other parts of the body are required to produce what the thyroid lacks

Avatar universal
Interesting subject Stella......worth trying to find out more too.
393685 tn?1425816122
I think AR has done alot of this research - I hope he responds
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