Hi
Would it be possible for someone to post the optimum ranges for all thyroid function tests so I can compare mine please . I am currently on 100mcg of Levo
There is so much great info and advice on here but I find it all very confusing
Thankyou
Optimum ranges for thyroid function : Hi Would... - Thyroid UK
Optimum ranges for thyroid function
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Coxyella51
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helvellaAdministrator
No! 
First, ranges vary from one laboratory to another. From one test manufacturer to another.
So any assessment of your results requires the reference intervals (ranges) that your lab uses. If you have had tests done at different labs, you will need the reference intervals for all of them.
Second, we are all different. I might do well with a Free T4 of 18 with a reference interval of 10 to 22. But someone else might find that is not high enough, or too high, for them.
It is often suggested that for those on treatment, we'd expect to see Free T4 and Free T3 fairly high in range. (You will see "upper third" quoted.) This might or might not be true for you. It is often the case, but not always.
And TSH simply does not track dosing adequately in those being treated with thyroid hormone. A high or low TSH might often make sense when very far out. But the closer you get to your best dose, the less useful TSH will be.
Ok thankyou The problem I have is that since being diagnosed with hypo I really haven’t well with so many symptoms !! I’m really trying to learn about the results and what they mean and how I can relate that to myself but with brain fog & memory I’m finding it hard to get a picture.
The last full test was 2019
TSH 1.3 (0.3-4.2)
FT4 21.4 (12- 22)
FT3 4.2 (3.1 -6.8)
GP tells me that the lab will only test now for others if TSH is out of range
My TSH keeps coming back within there normal range and yet I still have the symptoms
Any advice would be greatly appreciated
Do you have the actual results for the 'in- range' TSH results you have had since 2019 ?
ah , just noticed previous post's ... will have a look there
looking at previous post.. healthunlocked.com/thyroidu...
" Diagnosed with hypothyroidism in 2011
TSH 19.9 (0.3 - 5.5) FT4 7.2 (11 -23) FT3 4.4 (4.1-7.9) started on 50mcg Levo
Next results TSH 6.4 & FT4 12.4 same ref ranges upped Levo to 75mcg
TSH 2.2 FT4 14.1 FT3 4.4 increase to 100mcg
Left on 100mcg till 2013 always complaining of feeling tired achy dry skin constipation etc
In 2013 retested TSH 9.8 & FT4 13.6 upped to 125 mcg .
2014 parathyroid 2.76 (1.9 -7.64)
Tsh 0.69 & FT4 17.5
2017 TSH 0.44 & FT4 20.1
TSH 1.3 & FT4 22
In 2019 TSH 1.3 (0.3-4.2)
FT4 21.4 (12-22)
FT3 4.2 (3.1- 6.8 lowered dose back to 100mcg
Last test 2021 TSH 1.1
B12 45.4 (197-771)
Folate 8.4 (4.6 -18.7)
Vit D 54
I also had an ultrasound showing chronic thyroiditis in 2019 but not acknowledged as this was an incidental finding . what was the reason for the dose reduction from 125 to 100mcg? "
The 2019 results were all within range, so there was no need for a reduction unless you were having symptoms of over medication, and even if you were it might have been better to reduce by less (maybe 112.5mcg , rather than back down to 100mcg )
how did you feel in 2019 on 125 mcg ? , and how did you feel after a couple of months on 100mcg ?
Being completely honest I have never really felt well since taking Levo .GP reduced to 100mcg as FT4 was 23.2 (12-22)
I’ve recently asked to increase back to 125 but she said no I am awaiting my endo appointment which was supposed to be early June but now been cancelled
ok, so that over range fT4 did give them a reason to reduce dose. however 25mcg might have been too much , and if they have only tested TSH on 100mcg, they can't be sure what your fT4 is now (or your fT3!)
Since they have referred you and it's been cancelled, i think it's reasonable to ask GP to retest properly on 100mcg , to see where fT4 is now on 100mcg .
your latest TSH 1.1 indicated that there might be room to increase Levo dose a little.. So possibly you could trial an increase to 112.5 mcg ....
Historically when you were previously on 100mcg your TSH eventually rose quite high to 9.8 , so at that point your TSH was saying "100mcg is not enough"
.....they will probably say that "TSH tells them all they need to know.. blah blah.." but point out the difference in TSH on these results :-
2017 TSH 0.44 & FT4 20.1
............TSH 1.3 & FT4 22
They show obviously that your TSH does not always relate to fT4.
TSH ought to be higher to correspond to lower fT4 levels... but we all know it doesn't always work like that.. So you can use that example as evidence that your latest TSH of 1.1 does not necessarily prove that your fT4 is still at /near the top of the range.
If you're struggling to get your head round it all (which is normal 
) ,the following explanation might help a bit :-
TSH( thyroid stimulating hormone) is a message from pituitary to thyroid to ask for more or less thyroid hormone (T4/3) to be produced.
(T4 is storage /transport form of thyroid hormone , it is converted into T3 in the cells by removing one iodine atom .. T4 has 4 - T3 has 3.. so it can fit onto the receptors and work. The thyroid also produces some 'ready made' T3)
Levothyroxine is synthetic T4.
When T4 is measure in the blood it is done using an fT4 test (free T4), which measures your thyroid's T4 + your Levo dose.
Imagine TSH and fT4/3 on opposite ends of a see-saw :-
As T4/3 go lower, TSH rises (to ask for more),
As T4/3 go higher, TSH lowers.
If T4/3 go too high, pituitary stops producing TSH for a while, so TSH becomes 'supressed' ie. unmeasurable which usually looks like this TSH <0.001
The other thing to point out to GP is that your fT3 result has never improved on Levo, It was just crawling into the bottom of the range 4.4 [4.1 - 7.9] at diagnosis (when you were 'overtly hypothyroid')
It was still 4.4 when on 75mcg with fT4 at 14 [11- 23],
It was even lower on 125mcg 4.2 [4.1 -7.8] when fT4 was top of the range 21.4 [12-22] ** EDIT . oops , sorry , didn't notice range was changed , so 4.2 [3.1-6.8] is a little higher , but still only about 25% through range **
Reducing Levo to 100mcg may have reduced T3 further, or it may have increased it a little back to 4.4 ish.. (it could have done either of these because 'top of range' T4 sometimes does mean you actually get less T3....it's complicated ! )
However, the important point is that whatever level of levo you've been on your fT3 is still really crap , so since you've always felt crap, the obvious thing to try is to improve your fT3 level by giving you a little bit of T3 to try alongside your Levo...
GP's are not allowed to prescribe this unless an Endo starts it off , which is hopefully what an open minded endocrinologist would be considering once they see how low your fT3 is. (unfortunately an open minded NHS Endo is hard to find, but not impossible. ThyroidUK have a list)
T3 is the active thyroid hormone that actually makes your cells work.... not enough T3 = not enough action in the cells, and this affects different part's of the body in different ways, some organs can do a better job of making T3 out of 4 than others can.
Normal healthy people tend to have T4 and T3 at similar levels (as a '% through the range' ) , and in a lot of cases they actually have a higher T3 %through range than T4 % through range.
Thankyou so much for explaining to me This is kind of making more sense to me now.
I had a vague knowledge of the t4/t3 conversion and suspected that I was probably a poor converter . My next blood test is Friday I’ve just looked and testing TSH again and anti TTG . I’m guessing I will have to arrange private testing for full screen?
Any recommendations please would be appreciated.
I just want all the information and knowledge to present to Endo when I eventually get an appointment.
Previous experience with my endo is that they aren’t understanding or sympathetic to ongoing symptoms as long as TSH is within range !!
It is so very frustrating that we have to live with debilitating symptoms.
Seasidesusie's reply to this post gives links to the private test's we usually recommend. healthunlocked.com/thyroidu... and slowdragon 's last reply to this one also give links to full thyroid testing options
healthunlocked.com/thyroidu...
I suppose you could phone and ask GP to try and an ask for lab to include fT4 on friday even if TSH is an range.. they might still not do it even if she adds it to the request, but you never know.
It's useful evidence for Endo , (they may not be interested in private test results.) But the easiest way to get full thyroid and vit's is to test privately.
I notice you previously had TPOab's (thyroid peroxidase antibodies) done and it looked to be in range. these are usually raised in autoimmune thyroid disease , but not always, so maybe that is why they are now going to test for " anti TTG ? " usually written TGab (antithyroglubulin antibodies), so maybe "anti TTG" is something else.
I didn't realise you'd previously been seen by an endo.. if no good ( which is the norm!) ,You could send for the list of thyroid friendly endos from Dionne at ThyroidUK:
tukadmin@thyroiduk.org
Has your referral been 'cancelled' as in 'rejected - we don't think we need to see this person' or just cancelled as in 'postponed' until the dim and distant future ?....
Maybe now is time to try to make sure when you do see someone its someone worth seeing, as your results do point to you needing to try some T3 with your Levo, and a lot of NHS endo's just refuse to consider it, so it's a waste of time seeing them.
Just postponed until another appointment is available . Thyroid ultra sound showed chronic thyroiditis ( atrophic with coarse echo texture and slight lobular margin) .
I will email Thankyou
just out of interest .. what prompted them to do an ultrasound ?I didn't know they ever did them unless there was a swollen thyroid or lumps/nodules ... i want one ( an ultrasound, not a nodule )
I had a large swelling around the thyroid area which turned out to be a thyroglossal cyst therefore the whole of this area was scanned finding the state of the thyroid. This was 2019 so fairly tecent
Ah ok ,,, i can't come up with one of them .. i'll just have to carry on assuming my thyroid has 'shrunk '
That is a long time ago!
You might not remember, but how long between taking your levothyroxine and the blood draw for that test?
Do you have any other test results? Like ferritin (iron), folate, B12, full blood count, etc.?
Have you had a TSH more recently?
I have never been told before being on this forum about having a blood test early in the morning without thyroxine for 24 hours!I have one on Friday so I’m adopting that .
Nov 2019 TSH 0.53 (0.3 -4.2)
Feb 2020 TSH 1.8
July. TSH 0.97
Nov TSH. 1.1
Feb 2021 TSH 1.1 (0.3-4.2)
B12 454. (197-771)
Folate 8.4. (4.6-18.7)
Vit D 54
Full blood count 158. (120-150)
Most important question - How do you feel?
You need to optimise your low nutrients in order to support thyroid function/ conversion.
I expect your GP will only test TSH and maybe FT4, this only gives a glimpse into what might be going on.
For full evaluation you need to test TSH FT4, FT3, folate, ferritin, vit D, vit B12 and antibodies
On the face of things your TSH is acceptable....should be close to 1 when medicated. BUT, you have probably been told your result is 'normal" which only means it lies within the ref range, that does not mean it is optimal for you. In this case you will feel unwell.
I suspect your conversion is poor - high FT4 with low FT3. Your 2019 labs.
Low nutrients are most likely contributing to this.
There is no such thing as, "optimum ranges for all thyroid function tests" because test ranges differ from lab to lab and because we are all different and require an individual dosing regime. We need what makes us feel well.
The important reading is FT3. For good health T3, the active thyroid hormone, is required by the body's cells in an adequate and constant supply.
Many of us test privately -
thyroiduk.org/help-and-supp...
You may find this useful -
thyroiduk.org/if-you-are-hy...
We are all in this thyroid mess together so ask as many questions as you like. Members here have extensive personal experience which most medics do not...and they forget that we are not all text book cases!!.
Good luck
DD
When it comes to how I feel that is easy .. awful the majority of the time . I’ve been off work since February with varying degrees of symptoms high blood pressure anxiety tiredness and fatigue brain fog memory problems raynauds , I do not feel like the same person ! Interestingly I had been taking HRT which I am 99% sure has been interacting with Levo increasing the awful symptoms. I have now stopped this and do feel slightly better . When I look back to pre hypo diagnosis I definitely am not the same person I was.Getting the medical profession to listen is a constant battle they just make you feel like a neurotic hypochondriac, but I keep banging on to them about how I know my own body and it is not right.
Sadly that all sounds far too familiar....to me and many of us here.
It took me nearly 50 years (yes, 50) to find out why my health was very slowly deteriorating until almost age 70, when I could barely function I found this site and with member's support and much personal research I discovered the answer.
By that time much damage had been done, but, with self medication/monitoring, time and sheer determination I have improved considerably and on good days I can almost hide behind a "mask" and pretend to be a reasonably functioning human being!
I understand your frustration, my thyroid journey is related in my profile.
As I ( and others) have said you are suffering from low T3...there can be different reasons for this but first, optimise those nutrients, this may improve your poor conversion. If that doesn't work build a case for being prescribed T3 in addition to your levo....you will need to be referred to an endocrinologist for this.
Personally I would/did not entertain HRT which can affect the therapeutic effect of levothyroxine...particularly estrogen. I think your hunch is correct and stopping it should help, at least partially.
Your symptoms scream hypothyroidism.....but did your GP ask how you feel!
You should not have to, but you may find you have to do a lot of the spade work yourself.
The links I posted above should help.
Others have offered excellent advice
There is no quick fix ...so patience is paramount. In severe cases it can take years but perseverance will get you there! Thankfully someone warned me about this otherwise I may have just given up and suffered the consequences!
And, you are correct, we know our bodies better than anyone else....medics forget ( or rather, ignore) that. An old medic friend of mine always said, " Listen to your body"!
Your FT3 is too low. Your FT4 is possibly too high, depends, but you are not converting all that T4 to T3 very well. And that is the source of your problem.
T3 is the active hormone, so too little of it causes symptoms.
B12 45.4 (197-771)
Folate 8.4 (4.6 -18.7)
Vit D 54
These are all too low, and could be the reason you don't convert well. It would be advisable to supplement these nutrients until optimal. Did you have ferritin tested?
Ferritin was 62 ( 13-150)
Optimal vitamin levels are
Serum B12 at least over 500
Vitamin D at least over 80nmol and around 100nmol maybe better
Folate at least half way through range
Ferritin at least half way through range
What vitamin supplements are you currently taking
The aim of levothyroxine is to increase dose upwards in 25mcg steps until TSH is ALWAYS under 2
When adequately treated, TSH will often be well below one.
Most important results are ALWAYS Ft3 followed by Ft4.
When adequately treated Ft4 is usually in top third of range and Ft3 at least 60% through range (regardless of how low TSH is)
Extremely important to have optimal vitamin levels too as this helps reduce symptoms and improve how levothyroxine works
When on HRT almost all thyroid patients need dose increase in levothyroxine
All thyroid tests should be done as early as possible in morning before eating or drinking anything other than water and last dose levothyroxine 24 hours before test
Which brand of levothyroxine are you currently taking
Do you always get same brand
Many people find different brands are not interchangeable
Currently just vit D That’s interesting about the HRT as GP never mentioned that and I’ve stopped it now as I was feeling so much worse . I’ve recently swapped brands of Levo to aristo as previously was taking almus/ accord
Aristo is lactose free.
Some people find different brands are not interchangeable
Generally advisable to always get same brand at each prescription
Certainly need to retest thyroid levels 6-8 weeks after any dose or brand change in levothyroxine
Once you find a brand that suits you, best to make sure to only get that one at each prescription.
Watch out for brand change when dose is increased or at repeat prescription.
academic.oup.com/jcem/artic...
Physicians should: 1) alert patients that preparations may be switched at the pharmacy; 2) encourage patients to ask to remain on the same preparation at every pharmacy refill; and 3) make sure patients understand the need to have their TSH retested and the potential for dosing readjusted every time their LT4 preparation is switched (18).
Levothyroxine is an extremely fussy hormone and should always be taken on an empty stomach and then nothing apart from water for at least an hour after
Many people take Levothyroxine soon after waking, but it may be more convenient and perhaps more effective taken at bedtime
verywellhealth.com/best-tim...
No other medication or supplements at same as Levothyroxine, leave at least 2 hour gap.
Some like iron, calcium, magnesium, HRT, omeprazole or vitamin D should be four hours away
(Time gap doesn't apply to Vitamin D mouth spray)
If you normally take levothyroxine at bedtime/in night ...adjust timings as follows prior to blood test
If testing Monday morning, delay Saturday evening dose levothyroxine until Sunday morning. Delay Sunday evening dose levothyroxine until after blood test on Monday morning. Take Monday evening dose levothyroxine as per normal
REMEMBER.....very important....stop taking any supplements that contain biotin a week before ALL BLOOD TESTS as biotin can falsely affect test results - eg vitamin B complex
Low folate and B12
supplementing a good quality daily vitamin B complex, one with folate in (not folic acid) may be beneficial.This can help keep all B vitamins in balance and will help improve B12 levels too
Difference between folate and folic acid
chriskresser.com/folate-vs-...
Many Hashimoto’s patients have MTHFR gene variation and can have trouble processing folic acid.
thyroidpharmacist.com/artic...
B vitamins best taken after breakfast
Igennus Super B is good quality and cheap vitamin B complex. Contains folate. Full dose is two tablets per day. Many/most people may only need one tablet per day. Certainly only start on one per day (or even half tablet per day for first couple of weeks)
Or Thorne Basic B is another option that contain folate, but is large capsule
IMPORTANT......If you are taking vitamin B complex, or any supplements containing biotin, remember to stop these 7 days before ALL BLOOD TESTS , as biotin can falsely affect test results
endo.confex.com/endo/2016en...
endocrinenews.endocrine.org...
Low B12 symptoms
b12deficiency.info/signs-an...
If serum B12 result below 500, (Or active B12 below 70) recommended to be taking a B12 supplement as well as a B Complex (to balance all the B vitamins) initially for first 1-2 months, then once your serum B12 is over 500 (or Active B12 level has reached 70), stop the B12 and just carry on with the B Complex.
B12 sublingual lozenges
amazon.co.uk/Jarrow-Methylc...
That's pretty low, too. But, before supplementing that, it might be a good idea if you can get an iron panel done, and see what your serum iron looks like. But, these low nutrient levels could very well be why your conversion isn't good.
Does the test come under serum iron ? I had serum ferritin done in March
Result was 62 (13-150)
Ferritin is iron stores. Serum iron is the iron you have in your blood.
The iron in your blood can be quite high, even when the ferritin is low. In that case, it's not advisable to supplement iron.
But, if both ferritin and serum iron are low, then you need to supplement.
It's rather complicated, I'm afraid.
My brain is foggy all the time so processing all this information is hard😢Please give me a quick recap of supplements you recommend ? And I will get ordering
I’m thinking magnesium aswell?
Yes, I understand. It's not easy to take in so much information in one go, even without the brainfog!
So, with your levels, I would recommend taking:
Vit D - but I can't tell you how much, I think SlowDragon has covered that above.
Magnesium and vit K2-MK7 - which are the cofactors of vit D. You need about 350 mg magnesium, and to start with, if I were you, I'd go for magnesium citrate. You can consider other types of magnesium later, when you're feeling better and more able to cope.
Vit K2, the usual amount to take is 200 mcg.
And, a B complex containing both methylcobalamin (B12) and methylfolate, to bring up both B12 and folate. A good one is Igennus B complex, which you can find on Amazon (to make things easier )
That's enough to be getting on with. But, don't start them all at the same time. Leave at least two weeks before starting each one.
Hope that's understandable, but if you have any questions, don't hesitate to ask.
Thankyou so so much you’ve all been so helpful
You're very welcome.
Suggest you look at adding vitamin B complex first
After 10-14 days look at changing/increasing vitamin D
Vitamin D mouth spray by Better You with K2 included works well as avoids poor gut function
Look at adding magnesium after further 10-14 days
Magnesium must be 4 hours away from levothyroxine
B12 was typo it’s actually 454 ....still too low..but not dramatically low
Ouf! That's a relief! 45.4 was quite frightening!
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