Am having some issues at the moment with low ferritin, B12 and folate which I am seeing the gp about tomorrow. But also wondering after seeing a post on here about suppressed TSH being a marker for bone loss and heart issues what thoughts are of my results:
Feb 23
TSH. <0.02
FT4. 23.5 (7.9 - 14.4) range has changed from previous tests
FT3. 5.9 (3.8 -6.0) range has changed from previous tests
Results from previous years:
2022
TSH <0.02
FT3. 5.1 (3.1-6.8)
FT4 not tested
2021
TSH <0.02
FT4. 21.7 (12-22)
FT3. 4.5 (3.1-6.8)
I note the ranges for FT4 and FT3 have changed in the latest test which puts my FT4 result as out of range whereas before it has always been in range. Has anyone else found this with their results?
I think I am not over medicated as FT3 is within range, I don’t feel over medicated although I don’t feel too well at the moment due to the lack of iron etc.
Thoughts re suppressed TSH? I had a thyroidectomy years ago and take Levo 150mcg daily.
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Topes009
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Ferritin is low and has reduced over the last 6 months, folate and vit B 12 also reduced, all iron levels down. I have issues with another illness that has caused me to drastically adjust my diet but I have been supplementing with b vits etc.
However, the TSH has been at that level for years even when vitamin levels were good, I have always had issues with low ferritin which seems to go hand in hand with hashimoto
In Theory ... when the ref range changes significantly ( eg because lab buys new machine from a different manufacturer) .. the the" % through the range" of the new result should still be more or less the same .... the number for the 'result' would also be different ,not just the range :
eg if your blood was tested on machine A and the amount of T4 in your blood was "half way through the 95% population reference range for healthy people " ,
then you would get 17 [12-22]
and if you tested the SAME blood sample on machine B,
you would get 11 [7.9-14]
Both tests should still give similar % though range , and people who have "more T4 than the top of the 95% population range for healthy people " should be over range on both tests, (or under range on both tests if they had less than healthy people
My NHS lab has used that [7.9-14] fT4 range since 2018.... before that it used [8-18]
My personal suspicion is that the test platform that uses this 7.9-14 range does ?perhaps 'exaggerate' the result when it's already over the top end of the rage.
but i can't prove it .
My results immediately prior to the change were either 2 yrs previous / or odd for other reasons , so i don't have a direct before/ after comparison for my fT4 level on the 2 ranges .
The first one on the new range was fairly believable for 'my usual' levels.. it was
14.7 [7.9-14] 111% through range , which is not an unusual "%" for me .
My fT4 result since that first one were stupidly high for a couple of yrs.
20.5 ~206%
22.7 ~242%
19 ~ 181% .... surprisingly even at these levels i had no sign of overmedication...i did reduce by 25mcg though just to try it, but had to go back up by 12.5mcg because i got bad symptoms of under medication with 25mcg reduction ,
I have stayed on that slightly reduced dose since then and been ok .
As well as the low TSH issue ( or 'non issue' depending on your point of view) .. there are possible reasons to avoid having a T4 level higher than we really need it. ( T4 level , both our own and from Levo, has an association with some (but not all) types of 'cancer cell proliferation' ... higher T4 = 'more' proliferation . See my reply to this post healthunlocked.com/thyroidu... (3rd reply down ) for more details on that .
Your fT3 has gone up too though .. (both in the number itself, and as a % though range).. so it IS quite believable that your fT4 has 'really' gone up a bit too.
here's a useful calculator for converting results to a % through range, so result from labs using different ranges van be compared easily thyroid.dopiaza.org/
The whole situation with blood tests ,particularly for fT4 and fT3 is very unsatisfactory though ,, sometimes i really do wonder if the results are worth the paper they are written on .
Thanks for such a comprehensive and informative answer. I had no idea about the different machines and tests etc the articles and posts you linked are very useful.
The tests do seem very unreliable but if there is a risk with high FT4 then I am happy to try reducing the dose, I have done this in the past but when my FT4 was within range, I didn’t feel well so went back to the higher dose.
One thing I really don’t and never will understand is why the experts (endos) rely so heavily on tsh for people without a thyroid.
I am under an endo and have the option to try adding T3 to T4 but have delayed this due to starting HRT and wanting that to settle first. Maybe now is the time to explore that option; maybe it would help with the ferritin and other issues.
Are your results still high even with the slightly reduced dose?
Well , just to add to the general confusion about how thyroid hormones work ,
initially (i was feeling well despite the high fT4) my dose was reduced from 125mcg to 112.5mcg and the fT4 went UP ! .. from 20.5 to 22.7 [7.9-14]
So dose was further reduced to 106mcg ,then 100 over 3 months and the FT4 did come down a little to 19 [7.9-14]
but because 100mcg left me with horrible symptoms of undermedication (including chronic constipation and being unable to cross the road safely) we agreed to put it back to 112.5mcg despite the high fT4 level .
and 6 months after dose had been increased back up to 112.5 , the fT4 was DOWN a bit more at 16.6[7.9-14]
seems fT4 was just going on a little unexplained wander for reasons of it's own and then came down again when it was ready to stop messing about.
I haven't got my more recent results to hand (.see p.m. i sent you ) ... this little fT4 adventure was a couple of years ago now .
I have had suppressed TSH for about 18 years and till 18 months ago my T4 was always over range on T4 alone. I now take T4 and T3 and booth are within range at the upper end.
I have had 3 Dexa scans every 5 years during this time, the last one in January this year, and I have zero sign of osteoporosis - so suppressed TSH has had no detrimental effect on my bones. I have also been on HRT for 20 years and my Endo believes this has protected my bones.
Of course there are many, many factors which will affect individuals, and I had other things in my favour, such as being very active and doing lots of weight bearing exercise all my life. But for me suppressed TSH has not harmed my bones, nor heart.
thanks for the reply HandS. My TSH has been suppressed for years too, I’ve had 2 Dexa scans and both ok, no change between them over a period of 10 years, my heart is fine as far as I know.
How are you finding the T3, T4 mix? I think that’s the way to go for me next, have been waiting for my HRT to stabilise.
My experience of T4/T3 has been very positive and I wish I had been offered it years ago. I was preciously on 200mcg of Levo for years and years - had continued problems with episodes of feeling ‘hypo’, and gut issues . I feel better than I have for years on T4 and T3. I take 125mcg of Levo and 20mg of Lio and take them all together during the night - or as soon as I wake up . I take HRT at bedtime. Since changing to this, my recurring migraines have all bit disappeared and my gut now feels like it did before I became hypo. It’s say it took about 6 months plus to feel the benefits . I introduced T3 twice a day to begin with but had much better results by tasking once with T4.
Tbh - I now hardly think about it - which really does feel like freedom🙂 after many many years of struggling with being hypo.
That’s very good to hear. Like you say, to hardly think of it is freedom. I’ve found HRT to be a bumpy path but most definitely better on it than off. For me it’s the low ferritin and low mood, much worse since hitting peri menopause. Thanks for sharing your positive story, gives me hope and others reading this I’m sure.
I have just noticed all the typos in my post! Sorry🙂. But you got the drift ! I had a bumpy start with HRT too, but it was over 20 years ago and there wasn’t as much choice as there is now- but I have stuck to the same one since it settled. I came off for a while when I hade breast cancer - and it was hell on Earth . I went back on the same brand but the lowest dose. I had to stand my ground to get back on it - but now it’s never questioned. I’ve never seen any kind of specialist menopause person - shocking really - although it’s getting a lot of publicity now.
And from taking on board all the good advice on here, I have taken steps to optimise my vits and iron - and it is making a difference.
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