Thyroid UK

Blood test interpretation

Hi I have got my private blood test results back from blue horizon. They are saying it all seems normal. Feeling gutted as have had bad week with exhaustion and brain fog. They are as follows

Ferretin 38.1 (20-150)

Free t4 14.75 (13.9-26.1)

Free t3 4.65 (4.5-10.5)

Tsh 3.76 (1.36-8.8)

Anti-thyroid peroxide 8.1 <34

Vitamin b12 351 (142-725).

So it all seems in range. Any thoughts? Am I going mad?

8 Replies

Yes, they may be in the normal 'range' but not if you have symptoms. Your TSH is too high for you to feel good. Your B12 is low and should be towards the upper level and you can supplement with methylcobalamin sublingual B12. Your Free T3 is too low and should be towards the upper level and this is an excerpt from a response to your query a year ago:-

"Firstly with a TSH of 4.2 YOU ARE HYPOTHYROID but the process of becoming hypothyroid trashes Feritin and folate which is evidenced by your results

Ferritin MUST BE OVER 70 way are your results normal

you need to take iron plus at least 500mg Vit C to pull up the ferritin

obviously the ferroglobin is proving this to you

you also need to take a really good multivitamin last thing at night because again many vitamins get severly depleted by hypothyroid

Then when your GP finally decides to treat your hypothyroid with levothyroxine it stands a chance of working

Without ferritin being over 70 you will be unable to utilise the thyroxine because your body wont be able to convert the T4 which is thyroxine into the T3 your cells are screaming for "

Many doctors pay no attention to anything other than the TSH and your GP is probably waiting till yours reaches 10 and may never do so. You may have to have a private consultation and if you can afford one email for a list of doctors. This will be interesting for you:

Some have to self-medicate although it isn't ideal but you have been complaining for a long time now.

1 like

Rich72, TPOab 8.1 is negative for autoimmune thyroid disease (Hashimoto's).

Your results are within range but TSH >2 low in range FT4 and FT3 indicate your thyroid is struggling. Unfortunately, you are unlikely to get a diagnosis from your GP until either your TSH is over the lab range (usually 5 or 6) the practice uses or your FT4 &/or FT3 are below range.

Ask your GP to retest thyroid bloods in 6 months. Have the blood draw as early in the morning as possible and make it a fasting test other than water as TSH is highest early and before food and drink.

This link may help you get a diagnosis

Ferritin is very low, halfway through range is optimal. Supplement iron and take each tablet with 500mg-1,000mg vitamin C to aid absorption and minimise constipation.

B12 351 is low, <500 can cause neuropathy. Optimal is 1,000. Supplement 1,000mcg methylcobalamin sublingual lozenges, spray or patches and take a B Complex vitamin to keep the other B vits balanced.


Thanks so much I feel so grateful that complete strangers have helped me where the doctors won't. I will get myself supplemented and hope this helps until a doctor will diagnose. Thanks again I now know I'm not going mad which helps enormously to get through each day.... crawling off to bed now.....what a great forum

1 like

I hate to suggest further expensive blood tests but it's possible to be B12 deficient, with very similar effects to hypothyroidism, and for this not to show up in a B12 test. You may need the more useful Active-B12 or MMA test. It may be worth checking folate too. Look up the symptoms of B12 deficiency or pernicious anaemia and see if they apply to you. The PA Society has a checklist of symptoms online.

If you don't want to go that route, you can always try B12 skin patches (extra strong ones are available from Amazon) to see if they make any difference to you. They're not hugely expensive and you can't overdose or do yourself any harm. They are much more effective than tablets.

Your ferritin is still on the low side, so it might be worth building that up.

I suggest these because they're easy, cheap and DIY as a first option, and won't cause you any problems. Good luck!


Thanks I have been investigating the b12 options and agree the patches look good. Will leave you know how I get on thanks again


I've looked back on your posts and noticed that your B12 levels have dropped in a year since you were last tested and you also have severe fatigue, headaches, etc - all symptoms of B12 deficiency. I am wondering as you also have digestive issues, if you have an absorption problem with B12, which might account for the drop in levels. The levels, in any case, should be higher, as deficiencies begin to appear in the cerebral spinal fluid below 550 pg/ml. Autoimmune thyroid disease is in your family and this and PA/B12 deficiency are often interlinked, with symptoms overlapping.

The link below gives info and advice on writing to your GP and the excellent film explains why it is essential to treat quickly and adequately - it might be as well not to supplement at the moment as this will skew further tests.

Points from the Cmim/BMJ document Summary, if GP won't read full document:

* Vitamin B12 deficiency is a common but serious condition

* Clinical presentation may not be obvious thus leading to complex issues around diagnosis and treatment.

* There is no ideal test to define deficiency and therefore the clinical condition of the patient is of utmost importance."

* There is evidence that new techniques, such as measurement of holotranscobalamin and methylmalonic acid levels seem useful in more accurately defining deficiency.

* If clinical features suggest deficiency, then it is important to treat patients to avoid neurological impairment even if there may be discordance between test results and clinical features.

Severe deficiency shows evidence of bone marrow suppression, clear evidence of neurological features and risk of cardiomyopathy.

It is important to recognise that clinical features of deficiency can manifest without anaemia and also without low serum vitamin B12 levels. In these cases, treatment should still be given without delay."

Hope you have a good outcome Rich72.


Wow I have just looked through the symptoms of b12 deficiency and they do fit although with low iron and vitamin d it makes me think something is going on! I am unsure whether to supplement as will this mask other symptoms? However I am so desperate to feel better I feel it's worth a try. Is it better to hold off the loss of thyroid?

Sorry if this is a stupid question. One of the problems is when you feel so rubbish it's hard to see the wood for the trees


Not a stupid question. My sister and I have Hashi's and B12 def. and I feel better when thyroid is suppressed so I would say it's as well to get your thyroid treatment optimal as the others above have suggested.


You may also like...