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Thyroid UK
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Desirable levels of vit B12, folate, ferritin etc

Can anyone tell me what the desirable ranges are, not just what is considered "normal", please?

I appear to have symptoms that could indicate vitamin B12 deficiency, and as I also have Crohn's disease, I mentioned it to my gastro consultant. He seemed much keener to attribute it to anxiety than a physical cause, but agreed to run blood tests anyway.

I'm waiting for the results, but want to be know what I should be looking for.

He reluctantly agreed to test TSH AND FT4, but nothing else, since my previous thyroid tests have been "normal".

I have no diagnosis of thyroid problems.

32 Replies

To begin with there is no such thing as normal. In range - maybe - but then we are all so individual and no one size fits all. I have Crohns and had several surgical interventions in the past. I do not have a Terminal Ileum where most of the B12 is absorbed.

You will have mal-absorption problems due to the Crohns - your GP obviously does not have a clue. As it is also auto-immune then it is VERY important you are tested for Auto-immune Thyroid disease - Hashimotos.

Crohns like so many conditions is also linked to LOW VitD .


Click onto health Conditions on the above link and you will be able to see Crohns and the relevant articles I believe. If not type it into their Search Box.

So as well as the above tests you have mentioned you also need Anti-TPO - Anti-Tg. VitD - Ferritin - Folate - B12 - Iron - Folate. The last 5 all need to be OPTIMAL for you to feel well.... Ferritin around 80/90.


If you have any questions then please ask....


Thank you, Marx.

I have spoken to both my GP and gastroenterologist, and both have stated point blank that I do not have a thyroid problem, because my thyroid tests are within the accepted range.

It was my gastroenterologist that said my symptoms are absolutely indicative of an anxiety disorder.

My symptoms being: palpitations with low blood pressure, insomnia, pins and needles and numbness in my hands (mostly at night), lack of appetite, dry skin, hair thinning and going white suddenly at the temples, weight gain but now weight loss, extreme fatigue, anxiety, a feeling of weak muscles.

I have asked about being tested for antibodies and FT3, but told it's pointless because I do not have a thyroid problem.

Is there a standard B12 blood test that is used, or different ones? - I have seen serum mentioned, as well as active.


No wonder we get exasperated. Get a print-out of your blood tests for the thyroid gland. with the ranges (these are important) as labs differ throughout the country.

This is a link and you will see EXACTLY what the medical profession should know but don't. So, we continue to suffer in silence. You do have clinical symptoms which could well be hypo.


On the left hand side of the above link, there is also 'getting a diagnosis' plus the blood tests and what they mean and a list of symptoms which you can tick plus other info.

You can also have a private blood tests. I think the T3 would be the most important.


I have my results and the lab ranges:

TSH 2.6. (0.3-4.4)

FT4 14.2. (9.4-21)

These are my last results done 10 days ago.


So, you will see on the above link that it says 'consider hypothyroidism' for above 2. It also gives the other tests which should confirm.

There is also something called the Basal Temperature Test because if we are hypo we are usually cold and have low 'everything'.


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I've looked at the links, thanks.

I tried to discuss this with my gastro but couldn't get beyond, "So your TSH is well within range."

He went on to say that antibody tests would only show the likelihood or not of developing a thyroid disorder at some point in the future, so we're absolutely pointless.

I will check out the basal temperature stuff.


Tell your gastroenterologist that we dont want 'a TSH which is well within range'. We want a very low TSH which may well be very helpful in reducing our clinical symtpoms.

Who is this person (I've reread your second para). Antibodies tell us (the patient) that our body is under attack and if it is thyroid antibodies, we should be started on levo despite the TSH. As Dr Toft, ex President of the BTA, said that we should 'nip things in the bud' rather than let an attack continue till they are actually hypo.

By the way, why are you seeing a gastroenterologist?


I've been under the gastroenterologist for 5 years, because I have Crohn's.

I thought he was talking rubbish, but didn't feel I knew enough to argue - I tried my best! I said that I had read a TSH closer to 1 was preferable, but he just restated that the upper range was 4.4 and therefore my level was absolutely within range.

I actually broke down in tears of frustration in the appointment.


No wonder - some come across as so arrogant. As most Endocrinologists appear not to have much knowledge either, I doubt if many in the medical profession do.

They think we imagine all these symptoms because.......The TSH tells them so........

Considering it's nothing to do with the thyroid gland in the first place and doesn't always co-incide with sufficient thyroid hormones to make us well we remain chronically unwell and may develop other diseases.



Think it's time to go it alone. How can your Gastroenterologist say you do not have a thyroid problem if the anti-bodies and FT3 have NOT been tested. I have Hashimotos which was diagnosed here in Crete in 2005 - I was 59. If you care to click onto my name and read my Profile I think you will agree I have had a long history of being poorly and possibly know more about Crohns/Hashimotos/Thyroid than he does. The TSH - FT4 - FT3 were all IN RANGE but a scan revealed nodes and the Anti-TPO and AntiTg were HIGH and so I was diagnosed with Hashimotos. Had I had your Endo as my consultant I am presuming I would still be untreated....and crawling around with no energy and sleeping for 4 hours every afternoon. As it is I teach yoga 2/3 times a week - play tennis - walk my dog - run a business and spend time trying to help people find wellness :-)....and scrub up well for 68 :-)

Docs know little about auto-immunity and as you probably know that healing the gut is the very best thing you can do for your Crohns. Going gluten free is possibly your first step.

If you have read the B12 link I posted you will see some of your symptoms listed as you will in the Thyroid list. I would certainly go for Private Testing. If you really believe your Gastro Man and GP then sorting out Your FERRITIN/FOLATE/B12 could be a step in the right direction. Also do not forget those thyroid Anti-bodies ..... :-)


I have recently gone gluten- free, coincidentally - just a hunch I had.

I have a friend who has recently been diagnosed with Hashi's, with very similar symptoms to me and "normal" bloods too. She is in France, where things seem to be different from over here.

I am 45 and feel 90. I seem to be picking up bugs and not shaking them, I'm exhausted mentally and physically, I have gone off food, I wake up constantly in the night, my heart races for long periods.

I think private testing is the way forward for me - any suggestions what to look at first? Thyroid or B12? Or just do both together?


I really feel you must do both together as they are so linked. When you have time read through my posts to you in this thread. I have mentioned all the tests needed and posted good links for you to be well informed when discussing things with the medics ! I see information as power - the power to ask the right questions.

Your heart racing could be adrenals - which do become stressed when the body is chronically ill. I take large doses of VitC to support the Adrenals. I also take Selenium - B12 injections - B Complex - Mag - Zinc - K2 - VitD 10,000IU's. VitD is a steroidal pre-hormone as well as being anti-inflammatory. I posted a link for you for D and Crohns. After being ill for over 40 years I have completely foxed the Gastro Man here in Crete with my healthy gut !! I also am T3 only having started on T4 then a T4/T3 combo...


There is a good section on Adrenals - see top of the Homepage - and everything else come to that :-)

Happy to help where possible :-)

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Thanks for your invaluable information and advice.

I have recently started taking supplements - vit B complex, vit C, vit D, magnesium, fish oils, probiotics, L -glutamine, licorice root tablets, digestive enzymes, L-theanine and Menopace.

I will look into having a comrehensive set of blood tests done privately through Blue Horizon - they seem to offer them in my area.


Wow that is an impressive list. it will take a good 3 months to feel the benefits - as you probably know. I think having the tests done privately will give you piece of mind and prevent stressful conversations with the medics. YOU are in the driving seat. Living in Crete we choose our tests - go to a walk in lab - have printed results within two days which we keep along with scans etc. Some private but affordable and some NHS. OK Greece is bust but there are some good bits too :-)

Wishing you all the best and will look out for your posts. Do you take anything for your Crohns ?

Just as an added bit - when the T4 changes into the ACTIVE hormone T3 - the most receptors for this are in the brain - followed by the gut - now there's a surprise. So when T3 is low things go wrong as there is not enough to go around. Same with VitD - there are receptors for both on almost every cell in the body....

there has been research done here in Crete about VitD and people with Hashimotos....it's on PubMed.


Ha, yes - I am trying everything to help myself. Just about to add in zinc and selenium to the mix, as well as cQ 10.

A question - how on earth do you take that much vitamin D? I've just looked into "super strength" tablets, and they only come in at 1000 iu. Do you just take ten times the dose??

I am on Asacol only for Crohn's - the irony being that it is supposedly in remission. To be fair, it doesn't often cause me a problem, which is perhaps why my gastro puts everything else down to "anxiety". It doesn't pay to be a woman of a certain age, seemingly - clearly, we're all neurotic!

I have even ventured that my symptoms may be perimenopause...but that has repeatedly been met with "you're too young" - I'm 45!


I take Healthy Origins D3 5,000IU - so that's 2 a day with the K2 x 1. I have read that Big Pharma are trying to influence various bodies to restrict vitamins in large doses - I wonder why ? We also have a 2000IU pot ! Think the last lot were from Amazon.

Watch the Zinc - don't take it for too long - have a break like with Selenium. When Zinc gets too high it depletes Copper !! Have just read the transcript of a podcast with Dr Terry Wahls. She has a new book out on vits and minerals - may be worth buying ... :-)



So, looking at private testing, we're talking £126 for comprehensive thyroid testing...but more than £500 for it to include B12, ferritin, folate, vit D, selenium etc.

Will a GP vit B 12 test be enough? I don't know that we can find the money for the full caboodle privately. :-(

Actually, ignore that - just seen that the comprehensive tests have been discounted quite heavily on the website.


Try the GP first for Vit B12, Vit D, iron, ferritin and folate. The ones he wont do you can then get them privately.



I had B12, ferritin and folate tested last week (and possibly iron) - just waiting for the results. Don't think vit D was tested.


Hopefully it was as it a pro hormone and not just a vitamin.


Ah, ok - possibly then. I will check when the results come through, thanks.


I live in France, too. And whilst things are done 'differently', that doesn't automatically mean 'better'!

The first endo I saw tested TSH, FT4, FT3 and antibodies straight off. She said I was very hypo (which I was) but didn't mention the antibodies (I have hashi's) and had no idea how to treat me! She started me on 25 mcg levo, and when I got worse, instead of better - as so many people do - she told me it was because of my negative attitude!!!

Long story short, I've seen soooooo many doctors here, and none of them had a clue, most of them made me worse, rather than better, most doctors don't know what T3 is, NDT is illegal (as is HGH, which I also need but can't get!), labs are quite happy to test your FT3 but doctors ignore it and worship the TSH, and not one single doctor I have ever seen has any idea about nutrition or nutritional deficiencies - they all think vits and mins are unimportant!

So, don't envy your friend, she is going to have her share of difficulties, too!

Hugs, Grey


Thanks, Grey.

My friend has told me tonight that her best friend over there is a nurse - so she gets whatever tests she asks for. (She's an emergency room nurse, so no knowledge of thyroid - my friend researches and then asks for what tests she thinks she needs!) She has a consultation with someone in California - a Hashi specialist who has the condition himself.


Wow! A telephone consultation? How would that work? He won't be able to prescribe for her.


I'm not sure - maybe she's flying over there??!


Wow! This illness works out expensive!!! Hope it goes well for her.


I have Hashis and you seem to have the same symptoms as me. Please try and get those antibodies checked your Crohins is an autommuine disease I have colitis and that is also. I really feel for you but you're on the best site ever. They're a great bunch and only for them all I would not have got through the past year. Best of luck push your GP for the antibody test.


Thank you.

I am looking into having the antibody tests done privately.


Apologies - my keyboard doesn't recognise Marz!


potassium I think! Look up Dr. Berg on youtube regarding potassium! Levels in relation to sodium should be potassium 4 and sodium 1. He says blood tests for potassium are not accurate. Good luck!!


What I am aiming for :

Ferritin : Mid-range in whatever range is used for my tests (and that varies a lot)

Vitamin D : 100 - 120 nmol/L

Vitamin B12 : 1000 ng/L

Folate : 15 - 18 mcg/L

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I have put my results in a new post. Sadly, only ferritin was tested of the ones you posted...and it's not midrange.


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