how is my t3 optimal, but nothing else? - Thyroid UK

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how is my t3 optimal, but nothing else?

Jgoodwin977 profile image
36 Replies

Hello,

Just got my bloods redone for my 3 month review and was so happy to see my t3 was optimal for the first time, yet the rest of the panel has got worse! I was confused how the t4 was low if I needed it to get a good t3? If anyone could explain how this is possible I’d appreciate it.

I was sad to learn that my Ferritin is at its lowest when it was optimal only 3months ago and TPO has gone back up after I’d got it nearly into remission.

However my ldl cholesterol is at least now normal, as well as my sex hormone binding globulin.

Finally I was estrogen dominant and now got it down to the lower end of normal, but then I didn’t ovulate, which still makes me estrogen dominant by default as my progesterone is low as a result. It could be perimenopause, or is it due to the thyroid problem?

T3: 5.3 (3-7)

T4: 8.9 (9-23) optimal is 15-23

TSH: 3.2 (0.5-2)

TPO: 83 (<35)

I did the test first thing, fasted. Thanks

UPDATE

TSH: 3.2 mU/l (Range 0.27 - 4.2) 74.55%

FT4: 8.9 pmol/l (Range 8 - 18) 9.00%

FT3: 5.3 pmol/l (Range 4.3 - 7.1) 35.71%

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Jgoodwin977
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36 Replies
Hectorsmum2 profile image
Hectorsmum2

Are you taking T3?

Jgoodwin977 profile image
Jgoodwin977 in reply toHectorsmum2

no, I’m not taking any meds, only supplements

SlowDragon profile image
SlowDragonAdministrator

all thyroid blood tests early morning, ideally just before 9am, only drink water between waking and test and last dose levothyroxine 24 hours before test

This gives highest TSH, lowest FT4 and most consistent results. (Patient to patient tip)

T3 ….day before test split T3 as 2 or 3 smaller doses spread through the day, with last dose approximately 8-12 hours before test

so what are you taking,

How much Levothyroxine, how much T3

What vitamin supplements

Jgoodwin977 profile image
Jgoodwin977 in reply toSlowDragon

Yes, I have insomnia, so as mentioned I took the test as soon as I woke up and just had water.

I’m not taking any medication. Only supplements. It’s a long list, but I’m taking everything, even iron now as my ferritin was 15! I can write the list out if it’s helpful.

SlowDragon profile image
SlowDragonAdministrator in reply toJgoodwin977

Ft4 is below range

You need to see endocrinologist if GP still refuses to start you on levothyroxine

Here’s link for how to request Thyroid U.K.list of private Doctors emailed to you, but within the email a link to download list of recommended thyroid specialist endocrinologists

Ideally choose an endocrinologist to see privately initially and who also does NHS consultations so that might eventually transfer to NHS

thyroiduk.org/contact-us/ge...

Hectorsmum2 profile image
Hectorsmum2

you need to be on some hormone replacment. Your tSh is too high and T 4 too low. You are converting T4 to T3 well but I would imagine t3 will drop in time as your body wont be able to keep up.

Jgoodwin977 profile image
Jgoodwin977 in reply toHectorsmum2

it’s been improving over a year now and my GP said taking Levo would be like using a sledgehammer to kill a fly, so he’s just monitoring me now as the Endocs aren’t interested. It’s just strange as my tsh is unstable and my t4 was getting better at 13.6 3 months ago. It’s just a minefield

DippyDame profile image
DippyDame

With those results it looks as if your thyroid is failing...

Sometimes the diseased thyroid gland will start producing (very) high levels of T3 while, by comparison, producing normal/low levels of T4. This is to enable the body to keep functioning until replacement hormone is introduced....or the thyroid eventually fails.

You need to be treated with replacement thyroid hormone/ Levothyroxine starter dose 50mcg then tested again after 6/8 weeks and the dose reviewed

Jgoodwin977 profile image
Jgoodwin977 in reply toDippyDame

Thanks for this incite

Hectorsmum2 profile image
Hectorsmum2

You have hashimotos if your antibodies are high, your hormone levels will vary.

Jgoodwin977 profile image
Jgoodwin977 in reply toHectorsmum2

yes, I was diagnosed with hashimotos in 2018 with TGAB last at 88 and thyroid cancer in 2022. Good to know that my thyroid hormones will always vary due to the hashimotos. Thanks for that incite.

greygoose profile image
greygoose

Who told you your FT3 was 'optimal'? That's rather a bold thing to say! Optimal is not a number, it is how you feel. I would say your FT3 is euthyroid (normal) but when you look at the FT4 you see there's a problem there. It is below range. (Ignore other people's ideas of what is optimal and what is not, only you can tell that.) So, as DippyDame says, your thyroid is failing, and in a desperate attempt to keep you alive, it's stopped wasting its energy on making T4 and is concentrating on making T3, because that's the active hormone (this has nothing to do with conversion, by the way). But, it cannot keep that up eternally. Eventually it will burn out and stop making hormone all together. You GP obviously knows zero about thyroid, with his crazy comments (where do they find them?!?). You need to be on thyroid hormone replacement now, before things get worse - which they will. Time to start putting your foot down, I think: I want levo and I want it now! :)

Jgoodwin977 profile image
Jgoodwin977 in reply togreygoose

the optimal range for T3 is 3-7 pool/L you can see the research at the thyroidpharmacist.com

The weird thing is I feel fine, but not sure if that’s because I’ve been unwell for so long that I’ve normalised how I feel. I have ibs, but have done since I was 16, so that’s my only major complaint.

I have developed a nervous tick which I put down to being neurodiverse and my hair and nails grows slowly with cold feet sometimes, but I’ve got energy and not stressed or depressed so not sure why my bloods getting worse.

Usually people feel bad, but bloods are normal, mines the other way round. Maybe it’s the thyroid cancer that’s challenging it, but I’ve managed to shrink the tumour and my d-dimer has come right down to 435 from 4111 (normal range is 0-300)

Jazzw profile image
Jazzw in reply toJgoodwin977

Ah, right. You’ve been reading this page? thyroidpharmacist.com/artic...

Laboratory reference ranges vary from testing laboratory to testing laboratory and are different in different countries. And thyroidpharmacist isn’t based in the UK.

So you can’t describe a reference range as optimal—definitely not if the range you’re referring to isn’t the range that your testing laboratory used.

Are the laboratory reference ranges in your post above the ones on your actual test results?

Jgoodwin977 profile image
Jgoodwin977 in reply toJazzw

Sorry, my response posted in the wrong place:

I understand, but i understood that she was referring to an average.

However, the lab reference ranges for my tests are:

T3 is (4.2-7.1)

T4 is (8-18)

TSH is (0.27-4.2)

So I’m within normal range of all of them, but I don’t trust these ranges as they too broad.

My T4 is on the lower end of normal and TSH on the higher end of normal

greygoose profile image
greygoose in reply toJgoodwin977

No, that's not the 'optimal' range. That is the so-called 'normal' range. Not the same thing. This article might interest you, it explains how ranges are actually pretty useless:

helvella.blogspot.com/p/the...

If you think about it logically, all those possible results within that range, they couldn't all be optimal, could they? :)

Jgoodwin977 profile image
Jgoodwin977 in reply togreygoose

well there’s two separate ranges, a ‘normal’ one and optimal one. Not optimal results within the normal range

Show lab ranges for thyroid panel
Jazzw profile image
Jazzw in reply toJgoodwin977

That’s not quite how it works.

You need to use the laboratory reference range for your results. You can’t really use someone else’s definition of optimal in these circumstances, particular given you’ve previously mentioned you have thyroid cancer. There’s too much debate about what “normal” actually means.

Have a read of this: thyroiduk.org/testing/thyro...

Anyway… going by the reference range of your test, your FT3 isn’t optimal at all—it’s quite low in range. Which makes more sense in the context of your other results.

Your ferritin sounds rather low. It would be worth asking your doctor to run a full iron panel. It seems to have dropped lot since your last blood test.

Jgoodwin977 profile image
Jgoodwin977 in reply toJazzw

thanks, I was told that the lab ranges were too wide so not reliable, as they could say your normal when you’re not.

That’s why I went by the universal optimal range instead, but I get they use different measurements sometimes, so not always easy to convert.

Jgoodwin977 profile image
Jgoodwin977

I understand, but i understood that she was referring to an average.

However, the lab reference ranges for my tests are:

T3 is (4.2-7.1)

T4 is (8-18)

TSH is (0.27-4.2)

So I’m within normal range of all of them, but I don’t trust these ranges as they too broad.

My T4 is on the lower end of normal and TSH on the higher end of normal

greygoose profile image
greygoose in reply toJgoodwin977

And you're right not to trust them - see my reply above. But you cannot use just any old range to interpret your results. You have to use the range they've given you because that is the range to which the essay machine is calibrated.

Best thing to do is to convert the results to percentages:

thyroid.dopiaza.org/

FT3: 5.3 pmol/l (Range 4.3 - 7.1) 35.71%

So that give you a percentage of 35.71, which is far too low. It should be more like 50% in someone with a correctly functioning thyroid. So your FT3 is far from optimal.

Jazzw

Jgoodwin977 profile image
Jgoodwin977 in reply togreygoose

Thank you, that makes sense. However, 5.7 would be directly in the middle of 4.3 and 7.1, so it’s strange that it’s resulted in only 35.7-% and not like 49.6% instead ? 🤔

It says my TSH is optimal, even though it’s universally recommended to be under 2.5 at:

TSH: 3.2 mU/l (Range 0.27 - 4.2) 74.55% ? 😳

My T4 is still bad however at:

FT4: 8.9 pmol/l (Range 8 - 18) 9.00%

Thank you for this link btw

greygoose profile image
greygoose in reply toJgoodwin977

Well, that's what the calculator says, and it's never been wrong before.

There's no such thing as an 'optimal' TSH. The TSH is pretty much irrelevant because it doesn't do much once you're taking thyroid hormone replacement - and doesn't do an awful lot before. And it really doesn't matter what the range is or the percentage through the range. And the universe is wrong! 2.5 would be much too high for anybody's TSH. A euthyroid (i.e. with no thyroid problems) is around 1. Over two means your thyroid is struggling, and over 3 you're hypo. And, once on thyroid hormone replacement it should come down to 1 or under. But once it gets to 1, it's pretty useless as an indicator of thyroid status, so not too much attention should be paid to it. As someone else said, the TSH is just your pituitary's opinion of the amount of thyroid hormone in the blood. But the pituitary is biased due to how it works. You can have a suppressed TSH but still have low thyroid hormone levels. Doctors really, really shouldn't be so obsessed with the TSH, but they don't have the education to know any better.

Yes, your FT4 is awful, and does not correspond to your TSH at all, so It's pretty obvious that the pituitary is not doing it's job correctly, so the TSH should be ignored - and ignore all doctors that suggest it's optimal! lol

Jgoodwin977 profile image
Jgoodwin977 in reply togreygoose

Ok thank you for clarifying this

FallingInReverse profile image
FallingInReverse in reply toJgoodwin977

However, 5.7 would be directly in the middle of 4.3 and 7.1, so it’s strange that it’s resulted in only 35.7-% and not like 49.6% instead ? 🤔

You said 5.3 - not 5.7 - throughout this post for ft3. Hence the confusion.

Jgoodwin977 profile image
Jgoodwin977 in reply toFallingInReverse

Yes, I am 5.3 , I said 5.7 would be in the middle of the range, which I’m not far off, so that’s where I’m confused.

FallingInReverse profile image
FallingInReverse in reply toJgoodwin977

I was going to say that, it’s just the nature of small numbers. It’s far too easy for our brains to think “0.4” is a small change.

But it’s not at all when you look at the base you are starting from.

Yes, all you’d need is a .4 increase to get from 30% to 50%

In that range that is indeed a 20 point change.

It took me months/years to increase that much, as it does for many others here when done right, low, and slow.

Jgoodwin977 profile image
Jgoodwin977 in reply toFallingInReverse

ok, thanks for clarifying

Angel_of_the_North profile image
Angel_of_the_North in reply toJgoodwin977

5.7 is 50% of the T3 range: 2.8 units between bottom and top, so 50% =4.3 +1.4 = 5.7 (very unusual range). 5 would be 25% (4.3 + 0.7) so 36% approx sounds right.

When thyroid is failing, often FT3 is higher relatively than FT4, so you don't die

Jgoodwin977 profile image
Jgoodwin977 in reply toAngel_of_the_North

good to know, thanks. Would they ideally be even in a healthy thyroid then?

tattybogle profile image
tattybogle in reply toJgoodwin977

healthy people have more or less even T4/T3 levels yes .

some people naturally have T3 a little bit higher than T4 , and some naturally have T4 a little bit higher than T3 . but when you see bigger differences in T4 / T3 levels like T4 at the top with low end T3 levels , or reasonably ok T3 levels with low end / below range T4 levels , it's usually a sign that something is going wrong somewhere.

when the thyroid is starting to fail and T4 is lowering , the TSH goes up ...and the higher TSH causes the thyroid to make more T4 and more T3,, but it ALSO increases the ratio of T3 relative to T4 that it produces .

so in early thyroid failure it is common to see high TSh ..low T4 and reasonably ok looking T3... eventually if the thyroid gets worse, the fT3 will start to fall too.

sample of 10 (reportedly) healthy people with TSH / fT4 / fT3 results converted to % through range . These individuals have very different levels as their own personal 'normal' setpoint , but as you can see, they tend to have T4 and T3 levels that are reasonably close together . ie no one has T4 at 90% with T3 at 20% :

..
tattybogle profile image
tattybogle

just as an extreme example of why we need to be cautious when looking at any suggested 'optimal' figures :

there are many different test machines used to measure fT4 and fT3 .... and they all have different ref ranges.

in the uk currently there are some fT4 ranges that are [12 -22] and some that are [7.9 -14]

if you take the suggested optimal fT4 of "15-23" from the chart you found ..... it clearly cannot apply to a result of 15-23 from a machine calibrated to "95% population within [7.9-14] "

a result of 15-23 if it came from a machine calibrated to [7.9-14] would mean they had way more fT4 than 95% of the healthy population which is highly unlikely to be 'optimal' .

same applies to test machines calibrated to different fT3 ranges .... although the differences are less striking ... but for example some fT3 ranges are [3.1-6.8] .. while some are much lower / narrower ~ more like [2-4 ] 'ish' ... i can't find an accurate example off hand, but they do exist. .... so obviously a result of "5-7" from that machine would indicate very high levels of fT3 compared to 95% of the population...which is unlikely to be optimal for most of us .

the chart you found does give 'standard ref ranges', so at least we know what they were intending their 'optimal' levels to relate to... but the problem we face is that currently there is no standardisation of fT4 ranges or fT3 ranges, and until someone sorts that mess out we must be careful.

Converting everything we look at to "% through range" rather than an absolute number is probably the best way to do this a present.

Jgoodwin977 profile image
Jgoodwin977 in reply totattybogle

Thank you, I understand your point. The only thing I’d say is these labs using different ranges, could also be using different measurements, so may be a case of just converting perhaps. I wish they made it simple, instead of complicating things.

tattybogle profile image
tattybogle in reply toJgoodwin977

no the ones i mentioned are all measured in pmol . It needs the endocrinology profession to kick up a stink to push the manufacturers to standardise their equipment .. but as we all know , they are not bothered enough about looking in much detail at fT4 / fT3 levels. They are happy enough with looking at TSH and not so much bothered about what they see as inconsequential variations in fT4/ fT3 levels.

TSH tests are much more standardised across different manufacturers than fT4 and fT3 are.

helvella profile image
helvellaAdministrator in reply toJgoodwin977

If the ranges are the same but in different units, then calculating percent through range has the same effect as converting.

en.wikipedia.org/wiki/Thyro...

If we take 0.7 to 1.4 ng/dL and 9 to 18 pmol/L as the ranges in each type of unit, then the 50% point is 1.05 ng/dL or 13.5 pmol/L. You can use the percentage route, or multiply the ng/dL numbers by 12.857.

But, if the ranges do not map neatly, then conversion doesn't help. Whereas percent through range, for all its imperfections, still gives some idea.

Screenshot from WIki
Jgoodwin977 profile image
Jgoodwin977 in reply tohelvella

ok great thanks

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