Thyroid UK
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T3 to T4 Conversion Issues

Hello everyone, I posted this on another thread and was advised to create my own post (I think I broke the rules!)

I joined the forum on Wednesday so very much a newbie so please bear with me! I am very interested in many of the posts as I can recognise many of the problems in myself. I think the posts with regards to Adrenals may be an explanation of a problem that I have and is detailed at the foot.

Brief synopsis of me and my health history


Age 54

Type 1 Diabetes diagnosed age 12

UAT diagnosed age 27

Coeliac diagnosed age 43

Osteoperosis - diagnosed age 44

Low B12 diagnosed age 50 by GP blood test - helpful Endo tested for antibodies and it is not pernicious anaemia

UAT - age 27 no symptoms other than lump on my thyroid gland and as I had lost a bit of weight GP assumed overactive thyroid, tests came back normal.

Routine Diabetic clinic tests 6 months later showed underactive thyroid, still no symptoms other than lump.

Started on 50mcg of T4 which went up over the years to 225mcg. I am told by people who should know that no one should need that much and there must be something else wrong. For many years I had no symptoms of having UAT.

Problem - although TSH low and FT4 at upper end of normal over the last 10 years I am constantly cold, lethargic and despite almost starving myself either stay still weight wise or put on weight. I asked my GP to put me on T3 they said no. I asked to be referred to an Endo at another hospital as I knew he believed in listening to symptoms and that some patients require T3 & T4 and they said no.

Given my Coeliac I may not be absorbing my thyroxene completely or consistently BUT, could it be an inability to convert T4 to usable T3. I would appreciate your thoughts and any information I can use to convince my doctor that I should be on T3 & T4. Given I have 3 diagnosed autoimmune conditions could I have another auto immune condition affecting my Adrenal gland and ability to do the conversion?

Any help will be much appreciated

26 Replies

Have you had your thyroid antibodies tested. I am also coeliac and I have Hashimotos and sarcoidosis all autoimmune plus I have exactly the same problem you have and I am now on 275mcg of thyroxine but really feel I need T3


Hi Mia, yes I have Hashimotos so three auto immune conditions that have been diagnosed. You are on an even higher dose of T4 than me!


was advised to create my own post (I think I broke the rules!)

No, you didn't break the rules, the advice was given with good intentions! It is a fact that you are much more likely to get noticed, and therefore receive answers, comments etc if you start your own thread. :)


Thanks RedApple and it was good advice I know. Great site and I'm sure helping lots of people on it.


Welcome to the site.

Have you got any actual thyroid blood results that you can share with us? and what about your vitamins such as B12, VitD, iron, ferritin and folates, have you ever had any of these tested? If these are not at an optimal range for thyroid sufferers they can hinder both conversion and transportation of T3 into the cells - which is where they badly need to go.

If you do not have any blood results then maybe you could go to your GP's and ask for copies as without blood results its a bit of a guessing game as to what is going on.

Moggie x


If you think you might have conversion problems, insist that your doctor asks for your FreeT3 to be tested. Many labs refuse to do this unless pushed. Take a look at this video - which is a presentation to the Scottish Parliament on, amongst other things, the fact that some patients do not convert effectively.

If you think you might have adrenal problems, there is a good questionnaire here If you feel that sounds like you, consider getting the 24 hour saliva cortisol test done by Genova UK.

If you know that you have auto-immune issues there are two things you could consider. One is the autom-immune paleo diet -

and the other is Low Dose Naltrexone (which I've noticed is now being sold online by UK phamacies). and

Finally, if you don't already have them, buy one or both of these books - "Stop the thyroid madness" or "Your thyroid and how to keep it healthy".


Thank you for all the links and advice.

I have already watched the Scottish parliament video and both ladies presented their experiences very well. My own experience ties up with much of what they are saying. I know I have an underactive thyroid and that was diagnosed quickly and treated however at some point around 10 years ago I feel I have developed another problem which may be linked to my gut problem (Coeliac) or given I have been diagnosed with three auto immune conditions I could quite likely have another one affecting my adrenal gland and therefore conversion.

I have both the books too.

Moggie, my last bloods were done in May this year and my new GP gave me a print out at the time without me having to ask for it. She is much more patient oriented than my previous one. I studied them closely at the time but have looked everywhere and can' find it! The last print out I can find was when my TSH was 15 and the hospital were recommending that I moved up from 200mcg to 225mcg. In addition to this increase since then I am also being more careful about when I take my T4 as my grapefruit in the morning was preventing me absorbing the drug.

My B12 was low and I am on B12 injections every 3 months. I usually have full blood counts done each year by the Diabetic clinic, coeliac clinic, cardiac clinic so at least 3 times per year. I had a low white blood cell count and no infection so GP checked folates came back normal. I never got an explanation for the low white blood cell count! Two endocrine clinics and they still can't give me the correct treatment to help me feel well although they test my blood they aren't doing the correct tests. I will post the new blood results when I get them and thanks for your help.


Has Autoimmune Polyglandular Syndrome (APS) ever been mentioned to you? APS Type 2 is diagnosed if you have autoimmune adrenal insufficiency, autoimmune thyroid disease, and type 1 diabetes. Other autoimmune diseases can also be present. Here is a long article about this:

I think you should definitely seek tests for Addison's Disease / autoimmune adrenal insufficiency. Patient UK article here:'s-Disease.htm

Couple of comments about your B12 and folate. Firstly, 3 monthly injections are often insufficient to relieve symptoms. Secondly, you can test negative for intrinsic factor antibodies and parietal cell antibodies and still have PA (do you know what antibodies they tested?) and thirdly have you seen the folate result? GP will say normal when right at the bottom of the range.

Lots of B12 info here:


Dr Lowe states that many of us are on too low a dose of thyroid gland meds nowadays as before the TSH etc blood test came in, patients were dosed until all symptoms were gone and doses were between 200mcg and 400mcg.

This is an extract:-

Regarding effective dosages, our typical patient achieves optimal treatment results only when we adjust her dosage by the responses of her tissues to the hormone. Results are less than optimal when the patient’s thyroid hormone dosage is adjusted according to blood levels of hormones (such as the TSH and the free T3 and free T4). Every patient and every doctor should always bear in mind critical advice of Dr. Broda Barnes: Blood levels of any thyroid-related hormone are thoroughly irrelevant to finding a patient’s optimal dosage. What's important is the patient’s tissue response to a particular dosage of thyroid hormone


Thank you for posting this. I will follow the replies with interest as I also have Hashimoto's, Coeliac and last year developed Raynauds.. Have just upped my thyroxine from 75mcgm by half a 25mcgm tablet and it seems to have helped a bit. I've never been referred to an endo and my GP says he doesn't know what reverse T3 and T4 means. He obviously has no interest in finding out either.


Who diagnosed you with Hashimotos, your GP ?


Well over 10 years ago the GP I had then wanted me to take HRT. I was reluctant and asked her to do a hormone test to see if I really needed it. By chance she also checked thyroid and liver function. My TSH was 50 so she put me on thyroxine. I asked then for an antibodies test. I was told the treatment was the same so it didn't matter but I insisted that I needed to know if I should be looking at ways to stimulate my thyroid function if it was just underactive or not stimulate it if that was only going to increase the attack on it. I can't find the actual results but it showed quite high antibodies at the time. I've just managed to get a test for a T3 and T4 but they wouldn't test for antibodies again.


Can you afford to go to a private endo? The treatment on the nhs may be the same butthere are alternatives. Try and push for the endo :(


I can't afford a private endo at the moment as struggling to make ends meet. I'm trying to take on more work so may be able to then. If I feel brave enough I could try to persuade the GP to refer me but I'll have to give them some very good reasons!


I had the same issue. Luckily my results came back as potentially slightly over medicated and they referred me on that basis.


Was the endo helpful? It seems pot luck whether they are interested!


My nhs one, nope ! Got a follow up with him next week but my private kne has prescribed me t3. Just waiting for the abusive gp call telling me a child with a brain tumur is more important than me (which is what he said before).


Oh goodness Danifox6, that is appalling! I cannot believe the way some people in the NHS are trying to set different age groups or illness against each other. GPs shouldn't be acting like Gods deciding who is worthy of treatment and who isn't!!!!

1 like

Shocking aren't they. I think what gripes me more is I have worked my whole life and used private healthcare since I was born too. Now at 40 I lost my job due to illness in May and theywont help me. Ive had operations privately had my baby privately so have saved them a stak of money over the years, thousands and now I need them they are not there for me :(


I do agree, I had my baby privately and had a hysterectomy privately. I turned down a back op and had loads of chiropractic privately. Now I'm older and could do with some help to keep healthy and keep working, they are not interested.


Keep on at them and good luck :)


Thank you


Hampster, thank you so much for all this information. I realise it's better to know but If am terrified that I have Addisons. I have asked both Endo and GP why have I got more than one autoimmune condition I have 3 will that be it? Answer, most people have one but no guarantee that you won't have more. My feeling was that my Coeliac, Type 1 and Hashimotos were all symptoms the actual problem is my immune system. If I have PA then I have actually got 4 AI conditions. They just shake their heads and say there is not research to back that up! I have never heard of APS despite all the reading I have done on this and I will definitely read up more and go to the Dr and asked to be referred for tests. Over the last year I feel so unwell but quite non specific and this may be the answer. As I said I am terrified but I know it's better to know than not. I also have 2 congenital conditions that were found when I was 8 and then 43 these are hip dysplasia and bicuspid aortic heart valve so I have had to face two major operations, hip replacement and open heart surgery so I know I can deal with things but ....... Thanks.

I didn't ask what antibodies were tested for PA I just accepted that the Endo would know, a bit silly really given my Dr experiences and again I just accepted the B12 and folates is normal.

EmJB you must be feeling a bit anxious too but with the right information, test we should be able to live a good and happy life.


Goodness gaelianbr, you are having a lot to cope with. I hope you get some real help and some answers soon. I hope the operations you are facing go as well as possible. My concerns are very minor compared to yours. Lots of good wishes on their way to you.


You are very brave to have faced all these health issues, and come through still asking questions and seeking answers.

I'm aware of autoimmune polyglandular (or polyendocrine) syndrome because Dr Chandy did a presentation about it at the Pernicious Anaemia Society Conference. The most famous sufferer of this disorder - JFK:

Some speculation in there but still fascinating stuff. Imagine running the most powerful country in the world feeling the way that we feel most of the time...

On the B12 front this is what you should know about the antibody tests:

"Anti-intrinsic factor antibody is extremely specific for pernicious anaemia, but has a low sensitivity (50%). Around half of people with pernicious anaemia will have anti-intrinsic factor antibody [Andres et al, 2004; Longmore et al, 2007]. If anti-intrinsic factor antibody is present, pernicious anaemia is very likely, but its absence does not rule out a diagnosis of pernicious anaemia."

So if you tested negative for IF antibodies it means nothing - the test only has a 50% hit rate, i.e. half of people with PA will test negative.

"Anti-parietal cell antibody is found in 90% of people with pernicious anaemia, but also in 3–10% of people without it [Longmore et al, 2007]. The sensitivity of anti-parietal cell antibody for pernicious anaemia is more than 90%. However, its specificity is 50%, which is much lower than that of anti-intrinsic factor antibody [Andres et al, 2004]."

So a lot more PA sufferers test positive for this one, but still missing 10% of people with the disorder.

Before you start worrying too much about Addisons and APS why don't you make sure you've optimised your B12 treatment? You may need more frequent injections, or folate and perhaps iron. The addition of a B-complex is recommended as well. If you're on Facebook you can join the following group for advise and support:

Or have a good read around the PAS forum, lots of info over there:


H x


Hi EmJB I have had the surgeries in 2004 and 2011 so well over those now. I just want to find out if I have a T4 /T3 conversion failure and why. I've listened again to Sandra and Lorraine at the Scottish parliament so I could have Adissons autoimmune condition which would fit me neatly into having APS or there is possibly another reason I am now not converting correctly. There seems to be tests available privately for the latter and I'm lucky to have private medical insurance if I can convince my GP to refer.

We seem to be talking about two issues within this post probably my fault but the topics as I see it are 1) T3/T4 conversion failure (my post heading) but the other and where you fit in is 2) Multiple Autoimmune conditions one of which is Hashimotos maybe you could set up a post on this as I'm sure there are lots of people within the forum who fall within this and it would be good to understand if multiple autoimmune conditions is actually a condition in its own right?


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