Thyroid UK
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Very high B12-very worried :-(

I got my Blue Horizon results yesterday and it shows my B12 as:

Vit B12 H >1476 (Deficient <140

Insufficient 140-250 Consider reducing dose >725)

I'm very worried as I've been suffering from breathing problems and was admitted to hospital/ Cardiac ward last week. My hubby is urging me to go to the docs but I would prefer to have some input from you good folks first :-) (Sounds mad but I'm sure you know where I'm coming from!)

My other results were iffy too:

CRP 2.00 <5.0

Ferritin 119.1 2-0-150

TSH 2.82 0.27-4.20

T4 TOTAL 108.4 64.5 - 142.0

Free T4 20.89 12-22

Free T3 3.97 3.1 - 6.8

Serum Folate 32.29 8.83 -60.8

Anti-TPO H 423.1 <34

Anti TGA H 416.2 <115

I have Hashis, have been GF for over 3 years and am on the AIP diet for the 2nd time so I was really expecting to have better results but everything is worse since my last bloods in March. Any advice gratefully received! (I am on 125 Levo only).

10 Replies


Are you supplementing methylcobalamin?

TSH is high for someone taking 125mcg. FT4 is high in range so you might be more comfortable with some T3 added to Levothyroxine dose to raise FT3.

Folate and ferritin are good.

1 like

Thanks Clutter.

I take Methylcobalamin 2.5mg.

I am really disappointed by my Thyroid results as everything is worse that it was in March. I have resisted taking T3 but I think the time has now come! What would cause my TPOs to stubbornly remain as high do you think?



Methylcobalamin 2.5mg is a high dose and that's why B12 is high. You can't overdose on methylcobalamin so it isn't a problem having high B12 when you are supplementing but there's no point in peeing out expensive supplements so you might as well reduce to 1mg dose.

Not everyone finds antibodies respond to dietary changes. High TSH stimulating your thyroid gland may be why antibodies remain high. Suppressing TSH <0.1 will reduce stimulation and antibodies may drop.


Many thanks Clutter. So having high levels isn't dangerous then?

My antibodies were originally 1600 when I was first diagnosed so they have dropped considerably-but not enough!

How do I get my TSH down. T3?



A little T3 added to Levothyroxine will raise FT3 and bring down TSH without raising FT4.

1 like

Thanks :-)

I don't know if my thinking on this is a bit skewed but I really want to do this slowly, hopefully to minimise any reaction (hair loss in particular). I am on 125mcg Levo at present which I take in the early hours so how much would I have to reduce levo by and how little T3 can I take that would make a difference?

I have some Tiromel 25mcg (sell by date 8/2016!) - would this be OK or should I get some new?



I would add a quarter tablet (6.25mcg) to 125mcg Levothyroxine. You can take them together.

I was using some Tiromel recently which had an expiry date 2015 and it was fine.


Fabulous-thank you so much Clutter xx


More likley to be a problem with your relatively low FT3 than high B12 as most B12 just hangs around in the blood and doesn't get to where it is needed. I get low B12 symptoms (eye tics, loss of balance etc) if mine drops to 1000. Not converting FT4 to FT3 very well, by the look of it, even with good B12, folate and ferritin.


Thanks a lot Angel. I'm laying off the B12 for a little while. Does it just reduce by itself once you stop supplementing?

I'm starting T3 tonight (eek!)'s long overdue. Are conversion issues always because of gut problems? I'm taking L-glutamine, marshmallow and am on my 2nd bout of the leaky gut?AIP diet so am running out of things to try :-(


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