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More questions! I'm on loading dose for B12 and have results back from thyroid, wondering if this is to be expected please?

Hi, I'm having b12 loading dose at the moment ( after active b12came back bottom of range and MMA at 708 range being 0-280). The day after my 2nd injection I had a blood test to check Thyroid, ferritin, folate, IF and rbc.

Some results are back today and wondered if anyone can tell me if it's normal for TSH and T4 to change after starting B12 please?

Have given my previous results too...

December 2014

TSH 1.88mu/l (0.35-3.50)       T4 15 pmol(8-21)

Ferritin 12ug/l  (23-300).         B12 456

August 2015

TSH 0.42.           T4.  17

Ferritin 142.         B12 261 

I was having repeated sinus/ ear infections all last year so not really sure this ferritin was accurate?

March 2016

TSH 3.18        T4 13

Ferritin 24

Should have had folate and IF but awaiting these on printout once okayed by Doc.

Also diagnosed with low vitamin d 28nmol 50-120 last Feb and mild oesteopaenia. Took supplements, but stopped last Autumn as I couldn't be sure if they were part of the reason for feeling so ill and the persistent infections?

I thought the ferritin had prob gone down as I'm feeling more breathless, heavier periods back again and much shorter cycles so that's why I requested retest. I know I'll be told that it's fine as it's only ever been just over range for years.

Just wondering whether I should be requesting an iron panel and if so is it best not to start supplementation beforehand please?

Also, if I should expect my thyroid results to have changed after 2 injections and should I just retest later on, or look into checking antibodies do you think, that would be privately as have requested them before- no go. My nan (dad's mum) had treatment for overactive thyroid and Mum had a nodule?

Once again, many thanks for looking at these, not really sure if it's a B12 question for the PA site or a Thyroid question!

P.s am not feeling any better from b12 yet...4 the injection today, but realise that's expecting a bit much!:) thanks Jo

17 Replies

Hi Jo, Sorry you have not been well.

I am by no means an expert but I have been on daily B12 and Thyroid meds since 2003 and no there has been no difference in my levels over this time. I asked my specialist many years ago and she said " the only harm you can do with B12 is put it in a bath and drown in it!" I will take that as a no.

As to how many you need before you feel better- depends on how often you are having them and your levels. I felt a difference after 10 consecutive days. If yours are weekly then it will take time.

I know that when my thyroid levels are low I get really bad sinus infections. Am not sure what levels of T4 you are taking and if they have altered over the periods above but the TSH should be aprox 1 or under. Also the T4 levels seem low at the moment and Ferritin min level I recall is 11 so again not ideal. Just because they have been low for a while is not a good enough reason to give you no assistance.

I use MMM mineral mix by Dr Sarah Myhill and this helps me together with her Ascorbic acid powder. She once told me that very little in life has a perfect cure but by altering lots of things like diet, sleep ,supplements and meds each one can accumulate and have a large overall benefit. (see her web pages on ferritin etc for a more qualified opinion)

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Hi, many thanks For your reply Howard. I had to have a week between first 2 injections, then 2 last week because of Easter, then 3 this week, am going to ask for another week because of neurological symptoms! 

It's really interesting to know that your sinus infections are linked to thyroid levels. I had infections for years, diagnosed with polyps, given steroids, but diagnosed with chronic sinusitis and left to it. I had a York test and it said milk was a problem, and after giving that up I def saw an improvement, but then just kept getting other bugs and infections instead! 

Last year the sinusitis and inner ear infections returned, thought it was because I'd tried some goats milk, bit worried after the low vit d diagnosis, but not sure it could be responsible for nearly a years worth of persistent infections! Don't think I could hold a poor goat responsible for that!

I'm not on any treatment for thyroid, just trying to get to the bottom of a 17 year diagnosis of ME and looking for anything to help and these groups are brilliant. 

Yes, I def want to get my ferritin back up as I'm sure this is part of the reason I'm so exhausted, I know my brain fog eased a bit along with the breathlessness last year when the level improved, but unfortunately due to the infections and feeling so rough it's hard to tell what is responsible for what isn't it!

Yes, I've had spells of improvement over the years, but it has been under the help of nutritionists, but it is just so costly and they've tended to suggest supplementing so many things at a time. I shall look into the mineral mix you mentioned thanks. You're right it is a combination of things to get well, it's just getting the right ones! Plus if there's overlooked or underlying problems that need correcting I'm beginning to realise you can try as hard as you can with sleep and diet but still be barking up the wrong tree!

Can I ask what kind of B12 do you take daily now?

Thanks again for your advice and wishing you well...Jo :)


What do you mean by " brain fog " ? ... Does it feel like you can't get yr words out ... I forget things too ... It's awful !! 


Yes, it does feel like I can't find the right words or use different ones sometimes that have the same starting sound. It basically feels like there is a foggy lump of nothing where my brain should be, almost like a wall and I can't get to the quick thinking part anymore. I seem to struggle to take in any new information and certainly can't remember it very well. End up reading things over and over and they don't seem to sink in. It's like I'm waiting for something to wake up and get going in my mind all day, I keep trying, then it's back to bedtime again and it didn't seem to happen!!

I'm sure I've done things like switched them on, off to find I haven't, if I'm trying to write a simple note I can't seem to organise it, find the words and end up redoing it no end of times, all seems like hard work! 

Thanks for the Brazil nut tip, I used to be able to eat them okay, but after being diagnosed with a type1 latex allergy which cross reacts with foods was advised to be wary if them, so would need to pluck up courage to retry them and when you feel so ill you get worried about making it any worse don't you.

Happy Tuesday to you...Jo :)



I don't think having B12 injections or supplementing B12 affects thyroid levels.  It looks like your thyroid is beginning to fail as FT4 has dropped and TSH has risen.  NHS won't usually make a diagnosis until TSH is over range or FT4 <8.  You could try supplementing selenium which is good thyroid support.

Were you supplementing iron to have ferritin 142 in Aug 2015?  Ferritin is optimal half way through range.  Iron is available over the counter and online without prescription.  Take each tablet or sachet with 500-1,000mg vitamin C to aid absorption and minimise constipation.

Vitamin D is replete 75-200 and most people are comfortable with it around 100.  D3 is available in tablet, softgel oil capsules, nasal spray and drops.  If the vitD you were taking didn't suit perhaps you could try one of the other forms.


I am not a medical professional and this information is not intended to be a substitute for medical guidance from your own doctor. Please check with your personal physician before applying any of these suggestions.


Thanks very much Clutter once again. Will look into selenium, don't know much about it, but is it better to take separately or as part of a complex please?

Yes, I was supplementing iron from December, but had stopped taking it about a month prior to the 142 result, as I'd read it's not a good idea to take whilst having infections and thought it was not helping with the continued sinusitus, etc.

Yes, you're right I should prob retry vitamin d in a diff form, I was taking drops as I thought they might have a better chance of working. I've felt more I'll previously when taking cod liver oil, so just wondered if I'm one of those who doesn't get on well with it. My white blood cells went a bit out of range at the time too and I read on here vit d could do that, but maybe it was all a coincidence. 

Do you think it's worth testing those thyroid antibodies or should I aim to improve b12 and iron, plus selenium and retest at a later date?

Thanks again...Jo

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You'll need 100-200mcg selenium which is unlikely to be in a complex or multi-vit.

Try another form of D3.  Softgel capsules or spray is probably better than tablets. Some people don't get on with D3 and have to rely on sun exposure.

Some GPs don't test thyroid antibodies until TSH is over range.


I am not a medical professional and this information is not intended to be a substitute for medical guidance from your own doctor. Please check with your personal physician before applying any of these suggestions.


Thanks very much Clutter, will look into it. Why on earth do they have a range upper limit of 3.5 then not test until it's got to 8? Or does that tend to be the trend that you have to have really high TSH to have antibodies?

Jo :)



There's no treatment for autoimmune thyroid disease which is probably why it isn't tested until TSH is >3.5. Over range TSH in the presence of positive antibodies should ensure a diagnosis of hypothyroidism and treatment with Levothyroxine.




I eat Brazil nuts they are full of selenium ... Give you energy too 


Hi jo, just wondered if you had to fight to get yohr b12 injections. I'm fighting to get them and my level was 270! Just wondered if I could see your GP! :-) 

I hope the treatments work and you feel better soon.:-)

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Hi there...my fight has been a long one, was diagnosed with what was considered to be ME 17 years ago...am beginning to wonder now!

Yes, I originally looked into b12 a few years ago and a private test revealed it to be low 20os but was told that was fine. 

I've been back on the b12 trail after so much help from this group and getting considerably more ill. My Dr has firmly believed that I have plenty of B12 but said he was happy for me to buy and supplement vitamins. 

After discovering the Active B12 test and asking for it quite a few times I ended up writing a letter requesting a referral. After 2 months it was decided I could. This was last September...I then had probs getting 2 weeks clear of antibiotics to have the test. After having the first test rejected, then incurring various probs along the way it was retested end of Feb. The results were read by the wrong Doc at my surgery and i was told No Action, when clearly I needed treatment because the Active b12 was bottom of range and MMA read 708, should've been 0-280, so it's not been the easiest of journeys. :)

I then had so much help from this group, Dr Chandy and an email from St Thomas outlining treatment due to it being a deficiency at blood and tissue level, and gave this all to my Dr, so am now in the midst of injections!

So in my experience I would try the Active B12 test for £30 and give it a go as it could prove invaluable in your fight for injections. My symptoms alone weren't as most peoples seem not to be, enough to convince them, nor a lowish blood serum level, low ferritin and MCV just over range.

If you need any help with the Active B12 test, please ask...

Good luck...best wishes Jo


I'm glad you were able to get this sorted. But why do we always have to fight! Putting a letter together to my gp at the moment with all sorts of documents to support injections. If it's still no then I'll buy them from dr chandy who I've already contacted. 

I've been taking sublingual b12 lozenges. 

It shouldn't be this difficult! :-)


Hi jo5454,

Can I ask where you got the Active B12 tested for £30.

Thank you



Hi Josie, I had my Active B12 tested via post at St Thomas's hospital, London. It's £18 if you can get there,  £12 added on for P&P if you can't. It does need a referral letter from your GP and results go back to them, but obviously you can get a printout. There was a bit of deliberation about whether the blood sample needs to be separated from the clot and transit times, between them and my surgery but they reassured it was fine to have the blood taken late in the day ( mine was 4.30 to catch 5.15 post). It stated on the form that MMA is a further £96, but it seems if your Active B12 is found to be between 25-70 they test it for MMA automatically.

I chose them because they were NHS ( thought the results may be recognised then? ) and reasonably priced, with the option of MMA, but it depends on whether you can get a GP referral.

If you go ahead a little tip, make sure your name, gender, DOB, date and time of blood test and nhs number are all on the blood tube, as my first one was rejected and had to pay and do it all again.

They've been extremely helpful there and have answered questions about my results to me, really quickly.

I tried to roughly work out a possible result when deciding whether to have this, first converted my last blood serum b12 test 261 to pmol, came at 192 and then went on the fact that Active b12 is usually 10-30% so thought it may be somewhere between 19-57 so went along with that. As it was my result was 27 so probably around the 15% Mark.

What was your last b12 test result? If you need any more helplease ask, as I may have forgot something! 

Jo :)

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That's good to know, thanks Jo .  My last level was 2000. I'm not concerned at all as it means very little when supplementing. 

Keep well 



Forgot to say still searching, I chose StThomas as it is NHS and thought it might be more recognisable to my Dr...regards...Jo


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