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Thyroid UK
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T3/T4 ratio is high - what does this mean?

Hello everyone. I have had the Genova 24 hour urine test and I could do with help on the results.

T3 was 610 (592-1850)

T4 was 202 (347-1994)

T3:T4 ratio is 3.0 (high) (0.5-2.0)

So I understand I have low T4 production. But what I don't understand is that T4 converts to T3 and T3 is the active 'important' one. My T3 is in the normal range (albeit only just) so I guess that means I am maximising the T4 as much as I can.

But if T3 is the active one that we all need and I have enough why am I ill and why does that ratio matter so much?

I get it is out of sync but if I have an okay (ish) T3 shouldn't that mean that I am okay?

I'm obviously not okay but I just need to understand this and can't get my head around it. I have tried to read stuff but at the moment it is just a sea of words.

Can anyone help and give me a very basic explanation? I always value and rely on your opinions.

And one last thing - would an NHS doctor laugh in my face if I presented these results?

MP x

6 Replies

(My) basic information is that when we have enough suitable thyroid medication which suits us. We get well. Symptoms go and we have a normal life. Blood tests are only a gauge of what's in our blood, its whether our body responds to a particular thyroid gland medication.


Your T3 to T4 ratio is one aspect, but your results are still very low in the ranges - especially T4, don't you think? What the levels also indicate is that, at this level of thyroid hormone intake you seem to be converting sufficient T4 to T3.

If you read Shaws reply below, you can see that your need for thyroid medication may differ from someone else's, so even if your ratio is supposedly high, you may find that you still need more T4, so that your body can convert it to enough T3, to feel better. And don't forget, the tests - blood or urine - are only a guide. The best guide is how you feel, so given that you still feel ill, it seems to suggest that you need more thyroid hormone.



Thanks both for your replies. Sorry I should have said I am 'undiagnosed' and not on any medication apart from nutritional supplements. I have been to see Dr P who recommended the urnie test. He has now said our 'plan of action' now needs to be implemented - basically NAX and then Nutrithyroid to see if things improve. I am going to try this first but the reason i asked about the NHS doctor recognising this test is that, looking at my results, i reckon i made need something more at some point.

MP x


I don't know if your doctor would recognise Genova, but he/she may be sufficiently prodded by your having the test done because you feel poorly, as well as what the results might seem to indicate, to suggest an NHS blood test be performed. However, coming from a GP this will only be T4 and TSH - Thyroid Stimulating Hormone, so you may get no joy anyway since these tests, although adored and worshiped by the medical fraternity, are often misleading. Dr P is a very good place to start your journey and he will be able to guide you - he is an expert and fully understands what the blood results mean for you.

All the best.


thanks Schenks. Yes, been there done that with my own GP and blood tests. Have really given up on NHS to get a diagnosis so that's why I went to Dr P but don't really want to end up self medicating if I can help it, would rather see if there is any NHS doctor at all that would recognise urine test. Will do Dr P's protocol and see how I get on and then maybe look at practising private Endo who will take urine test into account. I still don't understand the ratio thing though and how that affects things so if you can shed any light??



You can start here: thyroid-rt3.com/ which is a site to begin to understand T3, and here thyroid-rt3.com/howisit.htm which will give you an understanding of the rT3/T3 ratio issues. Explore the former - take your time and don't try to grab at the information, and just follow the trail!

Good luck.


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