Thyroid UK

Hypothyroid, B12 Deficiency or Low Ferritin ?

Off to see Daughter's Doctor again next week, her symptoms are:-

* Gaining weight fast, despite being careful in what she eats.

* Tiredness even after a night's sleep.

* Brain Fog and concentration problems.

Blood Results:-

TSH 1.64 (0.2 - 4.5)

FT4 14.8 (9.0 - 24.0)

FT3 4.9 (2.5 - 5.7)

Vit D 90 (Adequate Level)

Vit B12 373 (180 - 910)

Serum Iron 14.9 (10.0 - 28.0)

Ferritin 23 (15.0 - 2.00.0)

Folate 12.8 (above 5.4 do not suggest deficiency)

Cholesterol Level 5.5 (3.1 - 6.5)

Daughter's Maternal Grandmother, Maternal Auntie and her Mum (myself) all have Hypothyroidism. When Daughter presented herself with her symptoms her Doctor said it might be her Thyroids, but not sure about what her results are telling us as they fall 'within range.'

Any ideas please. ?

(Her vitamin D bloods are OK due to her taking Vitamin D3.)

29 Replies

Vitamin b12 is far too low. I am currently sitting n the thyroid uk conference and we had a talk about this earlier today. Over 500 would be a better number to aim for and ferritin levels are usually considered best over 70.



Thank you galathea, I have heard that in Japan they like to keep their B12 bloods over 500.

Yes I thought Daughter's Ferritin was low too. I remember reading that ferritin had to be up to 90 if you have hair breakage or hair falling out problems.

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This is a link which was posted quite a while ago for your info.


Thank you for your link shaws, lots more is being learnt about low, (but 'within range') B12 bloods.


Coast, your daughter's ferritin is very low, optimal is 70-90. Low ferritin can suggest some form of anaemia although serum iron, B12 and folate are all in range. Maybe an idea to request a full iron panel. I decided to supplement 1,000mcg meethylocobalamin B12 when my B12 result was similar to your daughter's.

Her thyroid results look ok and her FT3, the active hormone, is good. Ask her GP to test for thyroid peroxidase and thyroglogulin antibodies to rule out autoimmune thyroid disease (Hashimoto's). Hypothyroid symptoms sometimes precede blood results by years :(

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Update, Daughter's Doctor has said tests all come back normal, I mentioned her low FT4, being low in range and not in the top third/quarter, but said he was not happy to prescribe medication, but said she could see an endocrine if she wanted, (would this be a waste of time do you think Clutter ?,) but Doctor has agreed to do the Thyroidperoxidase and Thyrogulin tests to rule out autoimmune thyroid disease, (Hashimotos,) as I mentioned that Hypothyroid Symptoms can show up years before your bloods shows anything is wrong.

Did not overload the Doctor with too much as I felt Daughter was lucky to get the other blood tests, she has to go back again so we'll get another chance to mention the 'within range,' but low ferritin and B12 bloods. (though easy enough to self treat as I do myself and now feel far better.)

Doctor said the tests would probably come back normal, so we'll be then left wondering why Daughter still has all the Hypo symptoms.

Thanks for your help Clutter, most appreciated.


Coast, If thyroid is being ruled out by your GP I think it may be worth emailing Sandy12 to find out more about THR. She's researched it extensively for her son.

I don't know whether or not an endo consult will be helpful. Too many focus on the TSH rather than the symptoms.

Bottom line, if your daughter isn't getting a diagnosis she may need to self medicate to see if hormone relieves her symptoms.


Thanks Clutter, have been in contact with Sandy12 :) and have learned 'lots.'

Your bottom line is also my bottom line Clutter, looks like it might have to be the way forward :)


Coast, having to self-medicate sucks but if it does relieve her symptoms then it is better than becoming more and more hypo until a diagnosis is made.


Yes definitely worth trying and for Hubby too who has aching weak muscles, again his FT4 is low in range, same as daughter's, he complains of less energy, tiredness, cold, aching muscles, also was low in B12, but B12 medication has not cured his weakened, aching muscles as we had hoped.

Rheumy said Hubby did not have a muscle problem. ???????????

Did not realize T3 was available without a prescription, I thought T4 and NDT you had to have a prescription with even if buying abroad so I just assumed T3 was also not allowed, (one should never presume ;) )


Coast, T4,T3 and NDT are prescription only in the UK. Some online sites don't require a prescription.


Thank Q Clutter, should have known this already :)


Apologies Clutter, have just read down further and seen more advice from you. Really worried about seeing an endo though.


An update Clutter,

We asked Daughter's Doctor for the TPO Antibodies and the Thyroglogulin A. which he agreed with, but unfortunately the Labs did not do them, decided only to test yet again for some reason, the thyroid tests and urea ones. This time daughters thyroid and TSH were both even lower, same ranges.

TSH 1.39 (0.2-4.5)

FT4 13.6 (9-14)

Doctor says she can see a more experienced than himself, 'Endocrine', but I am worried about seeing these people as if nothing happens and we go round in a circle due to 'within ranges' Daughter will not be able to go back to her own doctor for advice on these same matters. Now we are not sure which way to proceed or how to help her weight gain, over tiredness and brain fog, though she is now taking B12 5000iu and her brain fog isn't so bad, but she over sweats which does not tie in with Hypo.

Any advice Clutter please ? what would you do if in our shoes?


Coast, Your doctor should insist the lab does the antibodies and insist on FT3. If antibodies are positive it is worth your daughter trying gluten-free for 2/3 months. It may be worth trying anyway to see whether symptoms improve. Unfortunately, even if they are positive she's still unlikely to get treatment until TSH is over range though :( If your GP won't give a trial of Levothyroxine then the only remedy seems to be to self medicate for 3 months and see whether symptoms improve.


Many thanks Clutter, we have been invited back to see him and he was concerned the two tests were not done, didn't realize Doctors can insist bloods be done, so we will ask him again, thanks for the prompt :)

Her FT3 was done first time around when we asked, but not normally done Doctor said. We can sort the Ferritin and she is taking the B12, hopefully absorbing it. Will tell her about a gluten free period try out. I am also thinking more about Sandy12's Thyroid Hormone Resistance too, due to both TSH and FT4 both low in range and now even lower.

Thanks again Clutter.

FT3 4.9 (2.5-5.7)


Coast, Doctors can overrule the labs any time. They may have to in order to get the diagnostics to make a diagnosis.

TSH 1.39 is 'normal' for someone not on replacement. When it is higher it is responding to low circulating hormone (T3) and rises to stimulate production of more T4 for conversion.

It's surprising your daughter has hypothyroid symptoms with such a good FT3 so thyroid hormone resistance may be worth investigating. I think this would entail referral to an endo but you should research carefully who you see because most endos are diabetes experts and may not have the expertise or inclination to investigate THR.


So do you think it still worth having the TPO and Thyroglogulin tests done Clutter ?

She is tired, putting on weight, hardly eating to stop the weight going on and is often over heated, opposite of the 'cold' symptom her cholesterol level is ok.


Coast, most hypothyroidism is caused by autoimmune thyroid disease but NHS treatment is the same whether or not antibodies are there and treatment doesn't usually commence until TSH is over range.

Having one autoimmune disease does predispose you to others so it can be helpful to know and decide if, and what, lifestyle/dietary changes may help manage it.

Starving won't help with weight loss if the problem is hypothyroid, it will slow her metabolism further as her body will fight to retain any fat.


Many, thanks Clutter, it eventually sinks in. ;) :)


Thank you Clutter, agree Daughter's ferritin is very low, but showing 'within range.'

Both Hubby and I both take B12 as both our B12 bloods were quite low, but again 'within range.' We now feel far better and more energetic.

Yes her Thyroid does look OK ish and the FT3 is good, though her FT4 could be slightly higher as it is not sitting in the top third or top quarter, more towards the bottom quarter or bottom third, most people say they feel better in the top range.

Daughter has a very good Doctor who has already done many bloods, he guessed by her symptoms she might have a Thyroid problem, I will re check to see if the full iron panel has already been done (if not that might be the next step) and also get Daughter to ask about having a Thyroid Peroxidase and Thyroglogulin Antibodies to rule out Hashimoto's.

Many Thanks Clutter, most helpful.


Her thyroid tests don't look good to me. Both her FT4 and her FT3 are only just above mid-range. They should be higher - especially as she's showing symptoms. And I'm not surprised she has symptoms with such low Frees.

Yet her TSH isn't too bad. Have you considered a pituitary problem?

Hugs, Grey


Thanks for your input greygoose, yes they are lowish, we will get to the bottom of her symptoms eventually, Daughter has lost her spark and her energy levels have gone down weight gone on quick and this week she mentioned hair problems to me, which might be low ferritin connected, but luckily she still has her sense of humor and she certainly is not depressed.

No I hadn't considered a pituitary problem ?



Well, I just thought that her TSH didn't really correspond to the level of her Frees. It should be higher with Frees that low. So maybe it was the pituitary rather than the thyroid itself. Has she had a bang on the head at any time?


Yes, she has had many bangs on her head greygoose, apologies for my late reply.


OK, no problem. Took me a while to review this, had forgotten all about it. lol

So, despite what some others have said, I would say that her FT3 is too low, and I'm not surprised she's having symptoms. It's only just above mid-range. Remember, we're all different and this level may be way to low FOR HER.

FT4 on the other hand, is quite a bit below mid-range, which isn't right. On the bright side, she doesn't seem to be having problems with converting.

However, that TSH is more-or-less normal - perhaps a tad high... A truly 'normal' TSH, in someone who has absolutely no thyroid problems, would be about 0.8 to 1.25, last I heard. But it should be higher, IMHO given her frees. So, maybe an idea to look into her pituitary and check that that is functioning correctly?

Her iron and B12 are too low and should be supplimented because those levels are going to make her feel pretty bad.

Hope things have moved on a bit since you first posted - haven't had time to read all the posts to find out. Did you get those antibody tests?

Hugs, Grey


Apologies for you having to review my posting greygoose, no we didn't get the antibody tests, Doctor also like us were surprised the Lab/hospital had not done it, but in place had done yet another TSH and FT4 which showed both were now lower again at :-

TSH 1.39 (0.2-4.5)

FT4 13.6 (9-14)

We will ask him again to do the Anitbody tests to rule out hashimotos as I read somewhere it links with low, but within range FT4.

She is not on any medication apart from D3, and B12 vitamins,

but does have lots of sore throat problems, now I should know this one gg, how do you find out if the pituitary is functioning properly ? are there any blood tests for Pituitary or is it just MRI/ CT scans ? as I am thinking would her Doctor do further tests if everything is showing within range. ? he has already said he would not be treating her on medicating, though that was before her FT4 fell even lower.

I have heard that head/neck trauma can start off hypothyroidism.

;( No nothing has moved forward, we only heard about the tests not done on the Friday.

Thank you greygoose. :)


Thank you Sandy12, did wonder if she was having absorption problems with vitamins and minerals, members have said before that gut issues can cause weight gain.

Will check out THR.

Many thanks.


See where you are coming from greygoose, I do remember thinking that her TSH was very low and being a bit puzzled when I read out the results. I think she will have a humorous answer to the ''have you had a bang on the head,'' question when I ask her ;) but I will do.



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