Log in
Thyroid UK
93,732 members107,747 posts

Blood test results - confused!

This has probably been asked and answered a million times, so I apologise in advance for that! I've had thyroid issues since 1996 but still never really understood all the numbers and test results. This group has been a godsend for info tho!

I've never felt well, not properly well, and no amount of playing with doses has helped. My endo got me to a point that he said was as close as we were gonna get, and there is a note on my file not to change the dose. The GP wanted me to lower as she said blood results showed I was over-medicated, but I was reluctant so we compromised on me taking 225mcg/200mcg on alternate days. I don't know what the results were then and not sure what exactly was tested.

Recent blood results for thyroid were:

TSH <0.03

Free T4 22.2

Free T3 5.4

I also had loads of other tests which showed nothing really except Vit D deficiency and slightly raised liver bilirubin at 31umol/L.

I've been struggling a lot with how I feel - total exhaustion, jelly legs, eyesight issues, loads of other things that I have always put down to my dodgy thyroid.

But reading some of the posts on here, I'm not sure it is.

GP said the FT4 showed borderline hyper, yet all the symptoms point to hypo.

After all that waffle, I suppose I'm asking if someone with more knowledge than me can tell me what those blood results mean? Seems like one massive contradiction to me! Thanks :-)

12 Replies

I am not an expert but free T3 seems rather low. As your T4 is high perhaps its not converting properly to the active hormone T3 which is the one your body needs. There may be several reasons for this - low cortisol/DHEA (adrenal fatigue) or vitamin/mineral deficiency such as B12, folate, Vit D3, magnesium, ferritin/iron and copper/zinc. On the other hand some people don't do well on the synthetic levothyroxine.

Hope this helps



Hi Penny, it's really difficult to say anything without the ranges for the Frees. Do you have them?

I would also like to say that your doctor doesn't know what she's talking about when she say the T4 showed boarderline hyper. You cannot tell hyper from the T4. It is only a high T3 that makes one 'hyper' (i.e. over-medicated). But I can't tell if your T3 is high without the ranges.

I think that possibly what is happening is that you aren't converting all that T4 you are taking into T3, and it's the T3 you need to make you feel well. T4 is just a storage hormone and doesn't make you feel anything. So, my opinion is that your dose of T4 should be cut down a little and some T3 added in its place. Suggest this to your doctor and see how she feels about it. Although she's obviously pretty ignorant about thyroid! lol

Hugs, Grey


I think if your Bilirubin is elevated that you should be asking for another blood test called an autoimune profile, to rule out that you dont have an additional autoimmune problem. Blirubin is elevated when there is liver issues, and if you have one autoimmune problem, you're more likely to have another (ie PBC)


Thank you for the replies :-)

Ranges - sorry forgot!

TSH <0.03 (0.35 - 5.5)

FT4 22.2 (10.3 - 22.7)

FT3 5.4 (3.5 - 6.5)

Bilirubin 31umol/L (<21.0)

Vit D 65nmol/L (75.0 - 200.0)

I'm now on Vit D supplement (prescription one) for 60 days and then retest. I did start on an iron supplement in case low iron was making me tired, but iron levels are slap bang in mid range (without the supplement as I stopped taking it a while back). Vit B12 was 350 ng/L (range 211.0 - 911.0) which is low but within range.

According to a letter from my Endo, I actually have Hashimotos with multinodular goitre. I always thought I was just hypothyroid but if I understood what I read, they are two different things?? So confusing!

I have a condition called Hidradenitis Suppurativa which is a skin condition which is thought to be autoimmune and also been referred off for an MRI to rule out MS.

Will definitely speak to the GP about the autoimmune profile. I used to take T3 many years ago (can't remember why that stopped) so will also put that out there and see how it's taken.


OK, so your FT4 is high but not over the top. Your FT3 could be higher - most people need it right up the top of the range to feel well. Also, compared to your FT4, it isn't as high as it should be, so might be a bit of a convertion problem there.

Never mind that the B12 is 'in range', that's not what is important. What is important is WHERE it is in the range and yours is too low. I'm certain you would benefit from taking a supplement.

Don't worry about the difference between Hashimoto's and hypothyroid, the end result and the treatment are the same. Having Hashimoto's just means that it is the antibodies destroying your thyroid, but nobody has yet come up with a means of lowering or destroying the antibodies, so it doesn't make that much difference. The only thing is that Hashi's tends to swing between hypo and hyper, which confuses a lot of people - doctors included - and the only way I know to deal with that is to have a suppressed TSH - if your doctor will let you!

Anyway, the GP is wrong about the boarderline hyper (*******!), your FT3 is not nearly high enough for that! lol And I repeat what I said before, cutting down on some of the T4 and adding back in some T3 would probably be beneficial.

Hugs, Grey


Right, so (and sorry if I sound daft, I'm just trying to make sure I understand it all) it's the FT3 that is the important number? I think I'd have to get a referral back to the Endo to get T3 (he signed me off about 18 months ago) but not sure I'd get it (the T3 not the referral); keep reading lots of stuff about it being unavailable?

I couldn't understand how I was borderline hyper if I still felt so bad! Never been hyper ever.

I'll get a B12 supp. I'm guessing I don't have to ask the GP first seeing as I can get it from a shop. I read anything up to 2000ug is safe (will start low tho and work up).

Is there a Thyroid related reason why B12 would be low? Having a read on NHS Choices, I should be ok for B12 as I eat plenty of the foods they suggest.

Thanks :-)


The thyroid related reason is that when you are hypo, digestion is slow and that causes problems with absorbtion. We just don't absorb enough vitamins and minerals from the food we eat to keep us healthy.

Yes, FT3 is the important number, and it's criminal that they don't do the tests anymore. But, it's all about money! So what can you do...

Hugs, Grey


I was lucky they did FT3 on my tests. Mind you, they did *everything* on the form!

Thanks for all your help, I get it all a bit more now :-)


Sorry, another daft question!

What's suppressed TSH?


Below the reference range. xx


Thanks :-)


This is an excerpt from an archived site which has lots of useful info.(Synthroid is the USA levo) This is an extract and cursor to the question dated April 22, 2007:-

The second possible reason for your bad reaction to Synthroid is that T4-replacement simply won’t work for you. It doesn’t work for many hypothyroid patients. In a recent study in the United Kingdom, for example, T4-replacement left 50% of patient suffering from hypothyroid symptoms (Saravanan, P., Chau, W.F., Roberts, N., et al.: Psychological well-being in patients on ‘adequate doses of L-thyroxine: results of a large, controlled community-based questionnaire study. Clin. Endocrinol. (Oxf.), 57(5):577-585, 2002.) Unfortunately, through faulty reasoning, these researchers concluded that a much smaller percentage of patients suffered from symptoms despite being on T4-replacement. They are mistaken about the percentage. The evidence is overwhelming that T4-replacement is the lousiest approach to thyroid hormone therapy. I’ve documented the widespread failures of the approach in two critiques:



You may also like...