Is my B12 sufficient? : TSH 1.1 FT4 15pmol/l (1... - Thyroid UK

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Is my B12 sufficient?

canyouhearmeaya profile image
16 Replies

TSH 1.1

FT4 15pmol/l (10-22 range)

B12 723ng/L (190-660) - it says 'Above high reference limit'

However I see people on here talking about having a B12 of over 1000?! Am I low? Or is my doctor using a different measurement?

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16 Replies
SeasideSusie profile image
SeasideSusieRemembering

No you're not low, it's a good result. You may have seen me quote an extract from the book, "Could it be B12?" by Sally M. Pacholok:

"We believe that the 'normal' serum B12 threshold needs to be raised from 200 pg/ml to at least 450 pg/ml because deficiencies begin to appear in the cerebrospinal fluid below 550".

"For brain and nervous system health and prevention of disease in older adults, serum B12 levels should be maintained near or above 1000 pg/ml."

So if you're an older adult, like me, you might want it around the 1000 for the reasons stated, but it is a good result.

canyouhearmeaya profile image
canyouhearmeaya in reply toSeasideSusie

Ah okay, i'm a 26 year old male. So I guess it's nothing to worry about then!

SeasideSusie profile image
SeasideSusieRemembering in reply tocanyouhearmeaya

Yes, you're fine :)

canyouhearmeaya profile image
canyouhearmeaya in reply toSeasideSusie

Could my T4 of 15 being just below mid range (no medication) be causal of fatigue, brain fog, flat mood etc?

SeasideSusie profile image
SeasideSusieRemembering in reply tocanyouhearmeaya

I can't add much to what was said in your previous thread. You need all the tests mentioned to give a full thyroid and nutrient picture. And you might want to do the adrenal stress test - the 4 cortisol plus DHEA. I saw that you mentioned you took Ashwaghanda last year, which actually can lower cortisol.

If you want to do the adrenal test then I would suggest

Regenerus - thyroiduk.org/tuk/testing/r... who email the results direct to you or

Genova Diagnostics - thyroiduk.org/tuk/testing/g...

Adrenal Stress Profile (ASI): Cortisol/DHEA

Specimen requirements: Saliva

Cost: £82.00 (Discounted Price for TUK only)

Order Code: END01

Turnaround time: 7 - 10 days

and they send results to ThyroidUK, as your "practioner", who then send them on to you.

canyouhearmeaya profile image
canyouhearmeaya in reply toSeasideSusie

The blood test tomorrow I am having (alongside full thyroid panel including anti-bodies and rt3) is:

medichecks.com/hormone-test...

this does cortisol (only in morning via blood though) and DHEAs, + everything else mentioned. Would this be a good starting indicator if its adrenal related?

SeasideSusie profile image
SeasideSusieRemembering in reply tocanyouhearmeaya

All I have read tells me that the saliva test is the better test as it measures levels throughout the day, that test only gives waking cortisol and no other levels. Hard to interpret with just one result.

canyouhearmeaya profile image
canyouhearmeaya in reply toSeasideSusie

Okay I will see what results come back, and then if requires further investigation i will get a 4 or even better 6 point cortisol saliva check!

SeasideSusie profile image
SeasideSusieRemembering in reply tocanyouhearmeaya

If the 6 point check is Medichecks it wont include DHEA. Regenerus and Genova are better tests. To properly interpret an adrenal saliva test you need both cortisol and DHEA, you can see how to interpret them here

drmyhill.co.uk/wiki/Adrenal...

Dr Myhill's website is a mine of information, worth a moochy round.

canyouhearmeaya profile image
canyouhearmeaya in reply toSeasideSusie

Ah okay, thanks for pointing that out!

SlowDragon profile image
SlowDragonAdministrator

Did you get folate tested too? It works alongside B12

Low vitamin D can cause low mood. It's been a long grey winter. Government recommends all adults in UK supplement vitamin D from October to April. Do you?

Ferritin needs testing as well for Anaemia

Brain fog can be linked to gluten intolerance

canyouhearmeaya profile image
canyouhearmeaya

Not yet, tomorrow is full testing. Vitamin D is okay though, that was checked came in high.

The symptoms have gone on for 10+ years. Have tried removing gluten + dairy for 3+ months, nothing improved, and then when I re-introduced saw no worsening. (Removed again however as generally think it's probably better not to have in peoples diets.)

Brocolli and Kale seemed to be inducing extreme brainfog and fatigue in me recently, within 5 minutes of eating. Could goitrogens really have an effect that quickly?

Gambit62 profile image
Gambit62

I assume that you are supplementing - if so you might want to cut the supplements a little (unless you are symptomatic of B12 deficiency). B12 isn't toxic but in some people raised serum B12 can cause a reaction that makes the process that allows B12 to get from your blood and into your cells where it is needed less efficient, causing a deficiency at the cell level - all the symptoms of B12 deficiency but with high serum B12 levels.

The references is Sally Pachalok's book to higher levels refer to patients who are already symptomatic of B12 deficiency and probably being treated for a B12 absorption problem.

canyouhearmeaya profile image
canyouhearmeaya in reply toGambit62

No I don't supplement; why do you think that? Because they are over range?

I consume a fair amount of meat, so I expect that's why!

Gambit62 profile image
Gambit62 in reply tocanyouhearmeaya

meat is unlikely to result in your being over-range - some people just do have higher B12 levels and maybe you are one of them. However, there are a couple of medical problems that can also lead to B12 problems - liver and kidney problems - and it can be an early warning of problems. Suggest that you talk to your GP

This is an article on reasons for elevated B12 levels arguing that high levels should be investigated

watermark.silverchair.com/h...

canyouhearmeaya profile image
canyouhearmeaya in reply toGambit62

Having my liver and kidney checked on the blood test I had today. Thanks for pointing out, will look out for that on results!!

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