Hi all I'm new to this group so I hope my questions are ok for this forum.
I have been feeling very unwell for just over 4 months. the main symptom being extreme fatigue, plus memory / thought process problems / brain fog, tinnitus, aches & pains, pale skin, shortness of breath, weakness / feeling faint . I've been having tests at the doctors but as yet she has drawn a blank.
My recent B12 result was >150 pmol/L range - 25.10 - 165.00
Could some wise person / people please advise me on how functional B12 deficiency works and what would be the treatment.
ps: I have been a keen wine drinker for more years than I care to document. I wouldn't say alcoholic levels but more than is healthy. I have read this can play a part ?
Also, not sure if this is relevant but I am hypothyroid and ceoliac
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Kitti1
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functional deficiency is a B12 deficiency in your cells whilst your serum B12 levels are high.
some people react to high B12 levels in their blood by making the mechanism that allows B12 to pass into their cells less efficient - meaning that not enough B12 gets through to cells so processes don't run properly - this can lead to waste products building up - such as MMA and homocysteine so looking for elevated levels of these two products is one way of looking for a functional B12 deficiency but as they can be raised by other things they are tests that need to be done in a wider context.
Coeliacs and hypothyroidism are both conditions that can lead to problems absorbing vitamins and minerals (mechanisms not so clear in the case of hypothyroidism) but that would mean low levels of B12 which isn't the case with you.
Liver and kidney problems can result in raised B12 levels - liver problems can cause the liver to dump it's stored of B12 which will then result in a deficiency - kidney problems mean that the body stops removing unneeded/unusable B12 as efficiently, so levels build up in your blood. Heavy drinking could cause liver damage that would result in dumping of B12.
Did you have a full blood count and did it show any signs of anaemia? what did folate levels look like? what were your iron levels like?
This is a link to an article on using raised serum cobalamin (B12) as a diagnostic tool
Re my liver test results, so far they have come back in range. I think she said my gamma was borderline over range, but apart from that ok. Although she did say that this doesn't necessarily mean there isn't a problem.
As far as I am aware my kidneys are fine. No pain or adverse results.
Re my full blood count, my white cell count was over range (possibly due to my newly acquired hay fever ?) and my MCH was also over range - one of the factors that have lead me to the possible conclusion of Functional B12 Deficiency.
My folate was borderline low / towards the bottom of range
Regards my iron levels & CRP they were both well above range in my first tests in early March. Which lead my doctor to go down the route of possible hemochromotosis. But they have both now dropped to within range. I had a bad bout of flu in February which could explain it ? Although they are both something I am concerned about because my iron has been at the top of range for 12 months, with CRP just over range for the same period. With being hypothyroid I have recently started self medicating with NDT (Naturally Desicated Thyroid) because levothyroxine has left me with debillitating symptoms for many many years. So I have private blood tests done which always include ferritin, folate, B12, D3 and CRP. My D3 was insufficient earlier this year which I have addressed with daily doses of 4000-5000 IU.
I started NDT last September and feel happy on the dose I am on. All my thyroid checks are coming back well in range, T4 mid range and T3 roughly 2/3's up the range. My TSH is suppressed but TSH is always suppressed on NDT. Although of course my doctor is now thinking thyroid due to the suppressed TSH and the possibility of being over medicated. I feel certain I am not over medicated. My body temperature is 36.5 / 36.6, which indicates, if anything, I am slightly under medicated (but not so much to produce such debilitating symptoms). I also don't have other symptoms of over medicated, for example a constant aching hunger, which I have experienced in the past whilst working towards the correct dose of NDT.
I do feel that these symptoms are too extreme to be thyroid related given my blood test results. I was also unable to speak to my doctor yesterday after coming across functional B12 deficiency as a possible cause for my symptoms.
Have you had serum B12 done as well as active B12 - and if so what were the results? active B12 is generally around 20%-30% of serum B12 - if the ratio is out of line it indicates that something else may be going on.
The precise results I gave you were from my Medichecks results in late January (symtptoms begun at the start of January). My doctors blood test was in early of March, but I didn't get a print out for that result. Although I remember her saying it was high in range. I will ask for that to be done when I have blood tests on Friday, thank you.
I have continued to do some reading this morning and something occurred to me, may it be possible that I could have an absorption problem with B12, meaning my B12 wouldn't necessarily be over range with some form of functional B12 deficiency ? I was reading that drinking alcohol, even moderately, can interfere with absorption. Particularly coupled with my coeliac disease. I am very careful with my diet but am very sensitive and it is easily set off. I was also 12-15 years with bad IBS before being diagnosed coeliac
an absorption problem would lead to low B12 levels in your blood.
Supplementing with very high amounts of B12 can lead to high levels of B12 even if you have an absorption problem but an absorption problem without supplementation would not result in high levels of B12 in your blood.
There is a lot more to B12 than absorbing it from your food. There is B12 getting from your blood into your cells and there is also how efficiently your cells use B12 once they have it. These problems are genetic in nature and, in the case of efficiency using B12 in your cells, rare.
Problems with getting B12 from your blood into your cells in the absence of high serum B12 is possible but is extremely rare in children and, as it would manifest early in life, not something that develops in adults.
In adults this reaction can be triggered by raised serum B12 levels - ie a latent genetic variant that is activated by high serum B12 ... but something would have happened to raise your B12 levels.
Whilst some people do have levels above the normal range and the majority will be okay at that level, you would expect B12 levels to be relatively constant (in the absence of an absorption problem) because the body is very good at regulating levels using stores in the liver and either getting rid of excess through your urine or adding it to the stores in the liver if they are getting depleted.
Thank you Gambit62 for that information, although I think I am quite confused now. Is all functional B12 deficiency of a genetic nature ? Apologies if I am misunderstanding things.
I realised that just over a year ago I had test results which showed quite low B12 and I subsequently supplemented for a few months. Might this be relevant ?
I am going to try and speak to my doctor on Tuesday and have blood tests arranged for next Friday, so i will certainly ask for these to be done at the same time. Many thanks for your input fbirder
the causes of functional deficiency as a result of processes not running correctly in your cells are genetic. The mechanism that results in high serum B12 making the process for getting B12 from your blood to your cell aren't fully understood - there are some known genetic factors but I don't think it is entirely clear that all of this is genetic. If it is then this one would seem to be a more common/more common set of genetic variants.
There are actually a few researches and medics who have expressed doubts that even MMA and homocysteine give the full picture in relation to functional deficiency but I would agree that it is very unlikely that they would still come back low if there was a functional deficiency.
Cells are likely to prioritise how they use B12. Homocysteine and MMA are products of the main processes but there are other elements of the cycles involving these that could be affected in some people and a few other processes that involve B12 that might not run properly if these have been prioritised.
I'd been quaffing wine for 3 decades...then major fatigue etc all my serum normal, USA health care don't care to understand malabsorption or mitochondria malfunctioning with b1, b9, b12 and methyl folate. My b12 diagnosis was late...but finally found a doctor who got me on vitamins. Fatigue was the first to go...
Hi Herbert123 Many thanks for your input and sorry to hear of your difficulties getting a diagnosis.
As has been suggested, I may be barking up the wrong tree, but after 4 months I'm beginning to feel desperate for an answer. My fear is the possibility of CFS / ME, so when I stumbled upon functional B12 deficiency at least I felt it offered hope for a relief from the symptoms. The fatigue particularly I find so frustratingly debilitating, as I am currently not even able to walk my dogs properly or some days not at all. So it is a good to hear that you were relieved of this awful fatigue following diagnosis and treatment.
Some say the only way to know of b12 deficiency is to try it esp since serum levels are confusing. How much and how long did you try b12 with zero change in your energy level?
When I was supplementing last year it wasn't due to symptoms, but to try and get my key nutrients optimal for my hypothyroidism. Although I do find it interesting and possibly significant that just over 12 months ago without supplementation I was low in range. When I supplemented (sorry can't remember the dose) the bottle was finished within 4/5 months but it wasn't vast quantities, just a standard top up dose. I haven't supplemented for 7- 8 months but my B12 is now right at the top of range.
Hopefully the tests people have recommended will give me an answer one way or the other. Thank you Herbert123 for your input.
Hi, Kitti1 - I was found to be B12 deficient 3 years ago. Then I was diagnosed with functional B12 deficiency because my MMA level was still raised and I was still symptomatic on 1 injection every 3 months although serum B12 over top level (>2000 ng/L).
Haematologists tested my homocysteine and Active B12 levels and found them to be "normal" although MMA still raised*. Because of this, they decided that there must be another reason for this- and sent me for a Lactulose Breath Test, to see if it was SIBO (small intestine bacterial overgrowth) was causing raised MMA. Test result "suggestive of either SIBO or fast transit" (meaning probably IBS).
Gastroscopy revealed "flattened mucosal pattern in D1 and D2 : coeliac?" - biopsy disproved coeliac suggestion.
Still no concrete diagnosis. Self-injection with B12 every other day for 8 months along with supplements daily: folic acid, multi-vitamins, vitamin D (prescribed for osteoporosis of spine) and weekly Risedronate (prescribed for same) is slowly making me better. Hair, nails, skin all improved, corners of mouth no longer splitting or bleeding.... this particular symptom has been around for about 12 years! ... but cognitive impairment, dizziness/vertigo, memory problems persist (although improved ) and I'm obviously more keen to see the back of these as it makes work difficult. Currently doing only 1 day per week- then sleeping for about 15 hrs to recover. Seems to be the effort to concentrate and understand rather than the physical side that causes exhaustion. Otherwise the napping and falling asleep is no longer a problem and physical energy much improved, although some muscle wastage has occurred.
Recently had a 2-wk course of antibiotics for possible SIBO, although Gastroenterologist believes I have IBS. She cannot explain other symptoms, as neurologist found nothing wrong with my brain on MRI.
I don't think either of these are my main problem.
* Homocysteine and Active B12 levels were tested while on 1 a month B12 injections on NHS (reduced from 2 per week)- which will have affected outcome, although MMA remained raised when checked just before and after injection.
I hope this helps you decide what to ask for next and how to ensure results aren't flawed.
Best of luck with tests and let us know the results.
Hi Cherylclaire Thank you so much for the detailed account of the awful time you have been through. My heart goes out to you. I too find the cognitive symptoms very difficult to cope with. Initially bloods taken in mid March showed high iron & CRP (inflamation marker) which can indicate cancer. I went through a period of wondering if it was a brain tumor, scary ! But it is certainly one of the most frustrating things about it all - the not knowing and feeling in limbo. The raised iron and CRP were due to flu in February it turned out and they have now returned to "normal", so brain tumor & caner scar over.
I phoned the doctors today, the first day this week I have felt well enough to cope with the phone call, but was fended off the doctor by the receptionist. I explained everything to her and asked for the tests recommended for functional B12 deficiency to be added to my blood tests schedualed for tomorrow. The receptionist phoned back later and said she had spoken to the doctor. She said that they wouldn't be testing for functional B12 deficiency this time, but perhaps next time, Grrrr !
The drawn-outness of it all is so frustrating. How you coped having this not being properly diagnosed / dealt with for 3 years is beyond me. And I know what you mean when you say "normal" ranges ! I suspect so many of their ranges are wrong. I know for a fact the thyroid ones are and why I am getting tested again for my thyroid levels. I self medicate with NDT which suppresses the TSH test (I regularly have my levels checked privately and the important parts, the T4 & T3 levels are fine, just over mid range). But doctors have a bit of a melt down with a very low TSH. Fingers crossed it won't be as low tomorrow / I know it won't be as low tomorrow ! But believe me I know for a fact this is not thyroid.
Fingers crossed for answers soon and yes I will post my results & progress as it occurs.
I agree with Sleepybunny - Martyn Hooper's book is very helpful.
I've bought another copy recently (mine is highlighted, dog-eared and full of post-its because of poor memory ! ) and was thinking of giving it to my tireless GP. It would be an utter waste to give it to the two Haematologists who said "B12 is highly addictive" and "B12 is toxic and carcinogenic"- I'll let someone else waste valuable energy on that !
At first, I was told I was B12 deficient and would have to have injections - but nothing else. It was quite a shock when the nurse said they would probably be for life. That's when I found out about this forum, and the book. I did not wait to get home from the bookshop- went to the nearest cafe and read the chapter about his own experience. I thought "this is me"..the recognition made me cry. I stopped feeling quite so alone after that. For the first time, I realised what had been going on with me for such a long time, things I had ignored or excused...
One of the points he made was about auto-immune diseases often come in groups- he has Pernicious Anaemia and psoriasis, and considers himself lucky that he only has two ! This may strike a chord with you re. thyroid.
Because my sisters all have thyroid conditions (including Graves'), have just sent off for testing kit which includes anti-TPO and anti-TG - because not possible to get these done on NHS. I now think I may have exhausted all avenues, -and many consultants along the way !
Keep going, keep trying. Have found a lot of support here on bad days.
I wondered if your doctor has excluded possibility of lyme disease which has symptoms that can overlap with those of ME/CFS/b12 deficiency and a host of other health conditions.
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PLEASE HELP WITH SUSPECTED B12 FUNCTIONAL DEFICIENCY
Functional b12 deficiency 
Functional B12 deficiency?
