blood test interpretation: hi I’m new here, I’ve... - Thyroid UK

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blood test interpretation

Laundry profile image
37 Replies

hi I’m new here, I’ve just had a blood test that says my TSH is normal range (1) but my free thyroxine is low (9). I have so many symptons. Have been exhausted for years and been diagnosed with pmdd, depression, premenopausal etc but I’m wondering if this is what’s going on.

I’m also low iron and vit d.

Can anyone help me make sense of these results. In previous tests the gp has only ever done TSH and always said it’s ok.

Can anyone help me interpret these results?

37 Replies
SeasideSusie profile image

Welcome to the forum Laundry.

So that we can interpret your results can you please add the reference ranges that come with them as ranges vary from lab to lab, eg

TSH: 1 (0.27-4.2 )

Please add the iron and Vit D ones as well as the thyroid ones.

Laundry profile image
Laundry in reply to SeasideSusie

I’ve added pics of my blood results…

SlowDragon profile image

Was test done early morning- this gives highest TSH

Low vitamin levels tend to lower TSH

Low thyroid levels frequently results in low vitamin levels due to low stomach acid

Essential to test B12 and folate too

Plus thyroid antibodies for autoimmune thyroid disease

SlowDragon profile image

work on improving low vitamin D and low iron/ferritin

Then retest thyroid again in another 6-8 weeks

For full Thyroid evaluation you need TSH, FT4 and FT3 tested 

Also both TPO and TG thyroid antibodies tested at least once 

Very important to test vitamin D, folate, ferritin and B12 at least once year minimum

About 90% of primary hypothyroidism is autoimmune thyroid disease, usually diagnosed by high thyroid antibodies 

Autoimmune thyroid disease with goitre is Hashimoto’s

Autoimmune thyroid disease without goitre is Ord’s thyroiditis. 

Both are autoimmune and generally called Hashimoto’s.

Low vitamin levels are extremely common when hypothyroid, especially with autoimmune thyroid disease (Hashimoto’s or Ord’s thyroiditis)

20% of autoimmune thyroid patients never have high thyroid antibodies and ultrasound scan of thyroid can get diagnosis 

In U.K. medics hardly ever refer to autoimmune thyroid disease as Hashimoto’s (or Ord’s thyroiditis)

Recommended that all thyroid blood tests early morning, ideally just before 9am and last dose levothyroxine 24 hours before test 

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

Private tests are available as NHS currently rarely tests Ft3 or all relevant vitamins

List of private testing options and money off codes

Medichecks Thyroid plus antibodies and vitamins

Blue Horizon Thyroid Premium Gold includes antibodies, cortisol and vitamins

Just Thyroid includes BOTH TPO and TG antibodies -£49

If you can get GP to test vitamins then cheapest option for just TSH, FT4 and FT3

£32 (via NHS private service ) and 10% off if go on thyroid uk for code

Monitor My Health also now offer thyroid and vitamin testing, plus cholesterol and HBA1C for £65 

(Doesn’t include thyroid antibodies)

10% off code here

NHS easy postal kit vitamin D test £31 via

Only do private testing early Monday or Tuesday morning. 

Link about thyroid blood tests

Link about Hashimoto’s

Symptoms of hypothyroidism

Laundry profile image

Full results 1/3

Laundry profile image


Laundry profile image


Laundry profile image

full results above. Test was 10am.

My hormones are fine because I’m on HRT. And I’ve had b12 injections (trying to figure out the tiredness). D low, ferritin low, folate fine because of b-vit injections, haemoglobin low

I’ve read that normal TSH and low free thyroxine means secondary hypothyroid or pituitary/hypothalamus issues. Do you think I need to look into this further? Maybe private?

Jaydee1507 profile image
Jaydee1507Administrator in reply to Laundry

See SlowDragon reply about the other vitamins but your folate is not fine at only 2 points above being deficient. You would benefit from taking a good B complex to keep all the B's in balance. That contains B12 & folate. This one is 3 months supply and contains all you need.

Has your GP seen these results with the FT4 below range? Also your ferritin?

If you want to look at private doctors you can email for a list of Endocrinologists.

Laundry profile image
Laundry in reply to Jaydee1507

thank you for replying. I dropped these results to my gp and asked for someone to check them and ring back but I’m not holding my breath. I will look at the private list

Jaydee1507 profile image
Jaydee1507Administrator in reply to Laundry

What happened with your GP? You should at least be on iron tablets by now. Take 4 hours away from Levo and with a glass of orange juice for best absorpion.

What supplements have you been taking?

Have you adjusted your vit D dose and added K2?

Have you started the B complex?

Charlie-Farley profile image

Hi Laundry

I am not medically trained this comes from a person who has had to read up on her own condition and picked up a bit on the way AND still learning, but I would tend to agree.

Someone said to me the other day, central hypothyroidism is rare isn't it. I said not sure if it is rare or rarely diagnosed.... Has your doctor even batted an eyelid??? Many Doctors and Endo's (especially diabetes specialists) are not well versed on the most common form Hashimoto's. I'm one of many who have fallen foul of this lack of training and knowledge. My bio in my profile will explain. Even if you get a diagnosis off a doctor you may well come up against the SAME problems as us common old Hashi-Hypos.

Doctors drop kick you into blood test ranges and thinking 'all sorted'. Oh if only, and if they triumphantly tell you you are 'NORMAL' without first asking you how you feel - RED FLAG - These types treat the lab work not the patient.

You are reading and getting yourself genned up can't emphasise enough how important it is you continue and we will support - this is a fabulous forum and there are some very knowledgeable people here. I have found no better place to get advice myself.

you can get to bio /profile by clicking on my face

Charlie-Farley profile image

When you say exhausted for years??? And can you ever recall an accident, or illness after which you never felt quite right again? It's a retrospective look back that can build a picture. I had hypothyroid symptoms for over a decade, but the disparate random symptoms were only looked at on a case by case - never as a whole. Useful exercise.

Laundry profile image

I started thinking something was causing fatigue when I had my second son. He’s just turned 11! I put it down to having a newborn/hormones then after a while asked the dr if my iron was low or something. Ever times it’s been tested it’s been a bit low. My thyroid has been tested a few times but only TSH (when I look back)which has come back ok. After struggling on its been put down as iron, depression, pmdd, grief, anxiety, lockdown stress, perimenopause… etc etc

Ive tried every vitamin/supplement/anti depressant etc in a constant quest to feel better or like myself again. Full of life. Not someone who just wants to stay in bed and be left alone, no matter how little I do or how much sleep I get.

I’m exhausted, low, grumpy, everything too much hard work, I have aches and pains, I’m cold all the time, I have tennis elbow in both arms, my eye sight has deteriorated, I don’t play with my kids any more, i don’t go out anymore, I retain water, I’m a couple of stone too heavy and I can’t lose it no matter what I do/eat, my periods are awful and so is the hormonal rollercoaster.

I need help

Laundry profile image
Laundry in reply to Laundry

I’ve just read your bio. Sounds just like me. I cared for my dad for a very long time and when he died it all came crashing down. Maybe that’s something to do with it too. I also blamed grief and burnout for how u was feeling for a long long time

Jaydee1507 profile image
Jaydee1507Administrator in reply to Laundry

I'll tag Charlie-Farley as she wont get a notification that you have responded. When you reply to someone if you hit the reply button below the post you are responding to then they will get notified.

The way doctors test our thyroids has changed over the years and more and more they rely on the TSH which is very wrong. There are plenty of people out there like you with deficient free thyroid numbers. I hope you can get treatment now.

Charlie-Farley profile image
Charlie-Farley in reply to Laundry

There’s a lot of us out there, Laundry

Good advice about anaemia below

Charlie-Farley profile image
Charlie-Farley in reply to Laundry

you above

 “I’m cold all the time, I have tennis elbow in both arms, my eye sight has deteriorated, I don’t play with my kids any more, i don’t go out anymore, I retain water, I’m a couple of stone too heavy and I can’t lose it no matter what I do/eat, my periods are awful and so is the hormonal rollercoaster.”

Me below (minus kids)

I had loads of aches and pains and yes, tennis elbow in both elbows left and right and they sent me for nerve conduction tests and couldn’t find anything - once I was medicated that dissipated.

My eyesight has deteriorated.

I stopped going out a lot because I couldn’t go more than 20 minutes without going to the loo and once or twice I was so tired I had to go home after 10 minutes out. I was leaking, but once on therapeutic dose that stopped.

I’m past periods now, but so tired- yes crushingly, I felt like I was dying slowly.

I also had plantar fasciitis and that disappeared. I’ve never had since I’ve been on my therapeutic dose of levo.

I’ve done some self-help posts as well. You can look down the list and see them -they’re pretty obviously title - might be worth a read of those as well. Every single thing I’ve gone through I’ve tried to document in a way that other people can draw some benefit from. We are all different. Funnily enough though, there’s quite a few of us that have similarities, especially in the appalling treatment.

ThyroidLadyLondon profile image

low iron is so endemic in the UK, particularly among mums. Take an iron supplement or a good multivitamin with iron. Deffinitely take additional iodine and this is another endemic shortage among women of childbearing age in developed countries. This alone can do wonders, along with prioritising sleep and rest.

Laundry profile image
Laundry in reply to ThyroidLadyLondon

thank you for this. I’ve never thought of iodine. I try and take iron but I get horrific diaharria with tablets so I can only tolerate spatone which I think is quite low dose. Is there anywhere on here that has vitamin reccomendations?

ThyroidLadyLondon profile image
ThyroidLadyLondon in reply to Laundry

oddly enough, something like a post pregnancy/breastfeeding vitamin tends to have a really good balance of both iron, iodine and everything else besides in the right proportions. Thes iron doses tend to be quite low so are reasonably well tolerated.

Iodine is crucial for the thyroid to make thyroid hormones, along with iron and oxygen. Iodine is rapidly used up during pregnancy, so women who go into a pregnancy with low iodine, never kind several pregnancies (which is a huge population of women, but this is not mandatory to test during pregnancy in the UK, so most don’t know it), are at an even greater risk for thyroid complications later on. Add blood loss during birth and subsequent periods and low level anaemia, and you have a perfect storm for the thyroid. Oh I forget the sleep deprivation and having to return to work too early.

A great multivitamin and plenty of good sleep and rest can do absolute wonders for women suffering with a struggling thyroid and low energy.

Good luck!

Jaydee1507 profile image
Jaydee1507Administrator in reply to ThyroidLadyLondon

This group does not recommend either iodine or multivitamins. people here have very low vitamin levels and multi's just don't contain enough of anything to bring levels to optimal which is where we need them.

Iodine should be tested before taking it if needed. Its rare to be iodine deficient.

ThyroidLadyLondon profile image
ThyroidLadyLondon in reply to Jaydee1507

it is not rare to be iodine defficient, please see my reply further down on this point.

But I do absolutely agree it is better to be tested before starting to take anything. In the absence of being able to get tested (time and cost), a multivitamin is really unlikely to do any damage and very likely to help.

tattybogle profile image
tattybogle in reply to ThyroidLadyLondon

ThyroidLadyLondon ~ "Deffinitely take additional iodine"

well no , not as general advice, and not without knowing if iodine deficiency is actually the issue.

Iodine is certainly very important ~ the thyroid uses it to make T4 and T3 (T4 is made of 4 iodine atoms ,T3 is made of 3 ) So iodine deficiency is one cause of hypothyroidism.

BUT, iodine has complex (and contradictory) effects on thyroid .. in excess it can cause hypothyroidism,, AND it can also trigger hyperthyroidism.

This post has a list of useful information about iodine / thyroid :

please familiarise yourself with the potential effects of iodine before recommending it can cause thyroid problems if used inappropriately.

ThyroidLadyLondon profile image
ThyroidLadyLondon in reply to tattybogle

I have read the contradicting evidence on iodine and this contradictory advice is causing more harm than good. I agree that it is important to test for iodine deficiency before taking it, but this is a surprisingly difficult test to seek out through your gp. There is ample evidence that there IS a problem with iodine deficiency in the UK, and this particularly impacts women of childbearing age.

So whilst thyroid advocates are deliberating which bit of evidence to follow, many many thousands of women are a) not being tested for iodine during pregnancy, b) not being prescribed additional iodine during and after pregnancy and c) are ending up severely defficient after pregnancy.

So absolutely, testing is important, but in all likelyhood, living in the Uk with a typical Uk diet, mothers ARE iodine defficient.

Laundry profile image

does anyone know anything about secondary/ pituitary hypothy testing? Where to go? What do I need?

I think it might be what the normal TSH and low free T means but I’m very new to all this

I’ve taken my well woman blood test to the dr and asked them to look at it and ring me but I’d be surprised if anyone bothers

Jaydee1507 profile image
Jaydee1507Administrator in reply to Laundry

A GP would normally refer you to an Endocrinologist. It's possible that you have had low vitamin levels for a long time and that can affect the TSH and make it higher. When you get your vitamins back to optimal TSH can rise then.

Might be better to make an appointment to speak to a GP.

tattybogle profile image
tattybogle in reply to Laundry

UKmale_hypo has managed to get a diagnosis and treatment for central hypo and has posted useful information...... see replies from him on this post: (from here onwards)

Particularly this reply which has a link to an excellent letter he wrote which helped get a diagnosis :

Another member Wua13262348 also has central hypo (i think)

(click on thier names in blue to go to their profile pages to see their previous posts / replies.)

headinjuryhypo profile image
headinjuryhypo in reply to Laundry

Yes I agree about the central hypothyroidism possibility. Low TSH and low fT4 do indicate this "In central hypothyroidism, free T4 is low and TSH may be low, normal, or minimally elevated. " This link tells you more - treatment seems to be the same - levothyroxine. The likelihood is strengthened if you have deficiencies in other pituitary hormones, and if you've ever had a head injury, even mild.

csj113 profile image

hi, in my experience it’s sensible to tackle one thing at a time or it becomes impossible to untangle symptoms and causes.

You are definitely anaemic, probably triggered by second pregnancy. You also have iron deficiency with anaemia (low Ferritin which is a protein used to store iron). Your Ferritin level is considered extremely deficient. I would start by asking your GP if you would qualify for an iron infusion. If they say not, I would seriously consider a private one if you can afford it (unfortunately they are the best part of £800). When I had a Ferritin of the same level I had ALL your symptoms and more (hair loss too). If you can’t get an infusion you need one Ferrous Fumarate tablet daily or every second day (no more than that as you can’t absorb more than a specific amount in 24hr period). Take with OJ or a vit C tablet. An infusion will make you feel better in a couple of weeks. Tablets will work too but will take several months.

Get your folate and Vit D up too.

Once Haemoglobin normal and Ferritin > 50 see how you feel. Possibly HRT would be next step if you are Peri.

Then go back to look at thyroid - get a (might have to be private) test that shows TSH, T4, T3 and antibodies.

Good luck!

Laundry profile image
Laundry in reply to csj113

thanks for this. I’ve dreamed for years about having an iron drip that would wake me up😅 unfortunately that’s why out of my price range. I wonder what could get me one on the nhs or if there’s a cheaper way

SeasideSusie profile image


Please be cautious about some of the suggestions made here.

Take an iron supplement or a good multivitamin with iron. Deffinitely take additional iodine

Haemoglobin: 112 (115-165)

MCHC: 309 (310-360)

Below range haemoglobin can suggest anaemia. Low MCHC means that not enough haemoglobin is in the red blood cells and can suggest anaemia.

Ferritin: 8.2 (10-291)

Serum Iron: 17 (9-30.4)

Transferrin: 3.02 (2.5-3.8)

Iron Binding Capacity: 69.68 (44-76.1)

Transferrin saturation: 22.42% (18-55)

Optimal iron panel levels according to are:

Serum iron: 55 to 70% of the range, higher end for men - yours is 37.38%

Saturation: optimal is 35 to 45%, higher end for men - yours is 22.42%

Total Iron Binding Capacity (TIBC) or Transferrin: Low in range indicates lack of capacity for additional iron, High in range indicates body's need for supplemental iron - yours are 80% and 89.66% respectively

Ferritin: Low level virtually always indicates need for iron supplementation - yours is below range

Looking at your full iron panel your Ferritin being below range should concern your GP and alert him to possibly iron deficiency. Your saturation is below optimal, your TIBC and Transferrin are both high in range, all of which suggest you would benefit from iron supplementation which should be prescribed by your GP, not self supplemented, and regular monitoring of your levels should be done every couple of months.

Iodine deficiency in the UK is rare as we get plenty of iodine in a normal diet which includes milk, yogurt, cod, haddock, scampi, etc. Iodine solution used to be used to treat over active thyroid before the introduction of the current radioactive iodine treatment so it can cause hypothyroidism or make hypothyroidism worse. Iodine testing is essential before considering supplementing and a non-loading urine iodine test is said to be the better test.

TSH: 1.006 (0.55-4.78)

FT4: 9.2 (10.4-19.4)

I’ve read that normal TSH and low free thyroxine means secondary hypothyroid or pituitary/hypothalamus issues. Do you think I need to look into this further? Maybe private?

You are correct and the below range FT4 should hopefully alert your GP to the fact that there is a problem.

What could be indicated here is Central Hypothyroidism. This is where the problem lies with the hypothalamus or the pituitary rather than a problem with the thyroid gland. With Central Hypothyroidism the TSH can be low, normal or slightly raised, and the FT4 will be low.

TSH is a pituitary hormone, the pituitary checks to see if there is enough thyroid hormone, if not it sends a message to the thyroid to produce some. That message is TSH (Thyroid Stimulating Hormone). If there is enough hormone then there's no need for the pituitary to send the message to the thyroid so TSH remains low.

In Primary Hypothyroidism, which is where the thyroid fails, the TSH will be high.

However, with Central Hypothyroidism the signal isn't getting through for whatever reason so the message isn't getting through to the thyroid to produce hormone, hence low FT4. It could be due to a problem with the pituitary (Secondary Hypothyroidism) or the hypothalamus (Tertiary Hypothyroidism).

As Central Hypothyroidism isn't as common as Primary Hypothyroidism it's likely that your GP hasn't come across it before.

Your GP can look at BMJ Best Practice for information - here is something you can read without needing to be subscribed:

and another article which explains it:

and another here:

and another one:

A long read which you might find useful:

You could do some more research, print out anything that may help and show your GP.

You may need to be referred to an endocrinologist. If so then please make absolutely sure that it is a thyroid specialist that you see. Most endos are diabetes specialists and know little about the thyroid gland (they like to think they do and very often end up making us much more unwell that we were before seeing them). You can email ThyroidUK at

for the list of thyroid friendly endos. Then ask on the forum for feedback on any that you can get to. Then if your GP refers you, make sure it is to one recommended here. It's no guarantee that they will understand Central Hypothyroidism but it's better than seeing a diabetes specialist. You could also ask on the forum if anyone has been successful in getting a diagnosis of Central Hypothyroidism, possibly in your area which you'll have to mention of course.

Laundry profile image
Laundry in reply to SeasideSusie

thank you for all of this

Laundry profile image
Laundry in reply to SeasideSusie

so I went to the gp with my long list of symptons and questions and my blood results. I saw a locum. He said that - my thyroid is not an issue as TSH is fine. I said isn’t that a sign of central hypothyroisms? He didn’t listen he said the most they would do is monitor TSH as that’s the marker- he said no to iv iron. Said I am absorbing it but losing it do to my periods - he said I need to stop my periods with 350mg of progesterone as progesterone only pill didn’t work. I said I feel awful in the progesterone part of hrt so I’m concerned it’s going to make me feel worse. He said I’m too young for her. Stop taking it and take the progesterone to stop my periods- he said no to further investigations and vitamin blood testsI’m really upset by this awful advice

SeasideSusie profile image
SeasideSusieAdministrator in reply to Laundry

Did you use the articles on central hypothyroidism (CH) that I linked to? They explain why a seemingly normal TSH can mean hypothyroidism if FT4 is low suggesting CH.

he said no to iv iron

I don't think that your iron panel necessarily suggests than iv iron is needed. Your serum iron is now below range and it's not dire, it's low than optimal, it's your ferritin that is very low. Rather than iv iron maybe discuss iron tablets and regular monitoring with your GP.

I can't comment on progesterone/hrt as it's not something I have experience of.

Laundry profile image
Laundry in reply to SeasideSusie

I tried but he said my thyroid wasn’t a problem and couldn’t get me out of the door fast enough. I’ll try and see someone else and go armed with articles. I thought he’d listed based on blood results but he’s clearly clueless

Tanitha profile image

I'm no expert, and a different age to you, but can remember feeling exactly as you do now for many years and now back there again. Just wanted to offer a couple of things to consider.

You mention having b12 injections. Were they from the doctor with a loading dose and are they still continuing? I ask this as the loading doses dramatically, within a short space of time, changed my wellbeing, mood and energy which all dipped very quickly when not maintained.

Blood tests change and they are a snapshot at that time. If you look at mine and you will see how they have changed over 6 months which I do believe is due to vitamin deficiencies through absorption problems and on the advice given here started on vitamin d Friday and Thorne B basic (which arrived yesterday) - I can't wait any longer for doctors. If you can get your levels up you may see some improvement, no matter how small, which may indicate you are on the right path. Can I also suggest something which helped me dramatically - reduce chemical load on your body. By this I mean literally everything you go to use ie perfume, hairspray, plug-ins, cleaners, body locations and soaps, in particular anything with perfume including washing powder and softener. I was told this by a homeopathic doctor (also an NHS GP) 30 years ago and it was probably one of the best pieces of medical advice I ever received. It is an overload on your body. Put everything in a box and see if you feel any better after a few weeks. It's simple and free.

Try not to get too despondent about your experience with the doctor. We have all been there/are there and understand the frustration and desperation you feel. I have a diagnosis of Pernicious Anaemia on my records still but refused injections!

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