I have long suspected I have a B12 problem even though my active B12 blood tests are showing ok. I understand that there are conditions that mask the deficiency and stop the B12 actually being absorbed (if I understand rightly). I have the autoimmune condition of Hashimoto's and ME along with a current folate deficiency which I am taking supplements for, in case that is relevant.
To check if there is a problem with absorption I have seen things about intrinsic factor antibody tests but also something called MMA. What is the difference? Is one of these tests better/more likely to give more accurate results than the other? Or do I need both? Or something else?
Really want to rule this out asap.
Thank you.
Written by
PurpleNel
To view profiles and participate in discussions please or .
I too suffer with ME alongside of thyroid and other autoimmune conditions.
You are correct with your assumption that some conditions can mask a B12 deficiency - folate being one of them. Like yourself I were also prescribed folic acid which I believe maked my low b12 results !
I have also been prescribed Lansoprazole for many years which also adds to the dificiency. It seems that none of the tests carried out are of reliable source and often come back negative - but this does not mean you do not have a B12 issue.
I am a year and a half into being medicated with injections and still waiting further tests to find out the cause ! I went down the route of having private blood tests done which wasn't very expensive and done by a self finger prick test but if you could get a blood draw it would be better as the fingerprick test does not give a reliable reading of folate.
If you have recent blood results pop them on here for others with more knowledge than I too take a look at - together with your symptoms.
Thank you so much for taking the time to reply Jillymo.So how did you arrive at where you are now with medication by injection? Is this through the NHS or are you taking the route of sorting it out yourself as so many of us have to with our conditions?
My B12 was low hence the Dr starting me on B12 injections - to her that sorted my problem. I were gaving the most wretched symptoms so instead of 3monthly injections with a battle the Dr agreed to giving them every 2months.
I was really quite poorly and with all my other autoimmune conditions was going down hill fast. My Dr was simply treating the blood results the damned numbers she had in front of her - she didn't ask my symptoms or if I were in pain.
Like many others on here I now self inject but it has been a long journey to say the least. I am slowly making some progress but that is not down to my Dr who now insists I am to be seen by a neurologist - I would have thought my hematologist would have been her first port of call as it's a blood condition but hey ho who am I to question her reasoning.
I am a year and a half since being told I were B12 deficient and still waiting to be seen !
I hope you find some answer's and progress to better health. Remember ME is a label which there is no test for - I had other autoimmune conditions so always keep an open mind as to what else could be causing your symptoms.
Unfortunately I missed my neuro appointment thinking it was this month. š±
Due to having the sticky blood issue and anticoagulation treatment I have had various brain scans over the years which shows lesions in the white matter and small blood vessel changes.
My Dr is now trying to put my B12 symptoms down to the changes on my brain scan - which is annoying. I have two neuro's and a hematologist on the go one in London for my APs (sticky blood).
I find it very strange seeing that B12 deficiency is a blood condition my Gp has not contacted my hematologist ! š¤
IFAB is a test for PA as the specific cause of absorption problemsIts a problematic test as it isn't very sensitive and gives false negatives 40-60% of the time depending on the exact test method.
MMA is a metabolite that builds up if your cells don't have enough B12 to recycle it. Levels in the blood can also be affected by other things, such as kidney problems so the test needs to be done in a context that rules out those other causes.
Here's the difference. Intrinsic Factor Antibodies are yet another autoimmune antibody. The stomach produces IF via the Parietal Cells; the IF binds dietary B12 and facilitiates its absorbance in the ileum. The normal dietary B12 amount is so small, this helps the body to scavenge it from your diet. If you have antibodies to IF then they can block the binding site for B12, or the binding site for the ileal receptor, or both. Only 50% or so of patients with PA have these detectable antibodies.
Methyl Malonic Acid [MMA] is a functional assay. In B12 deficiency, higher MMA levels are likely to be seen.
So, IF antibodies may be a reason you aren't absorbing B12, and the MMA level is the result of having insufficient B12 whatever the cause of the low B12 level.
It's something to seek medical advice over; if you have a demonstrated low B12 level then your MMA is likely to be raised.
(In folate deficiency, raised levels of Homocysteine can be seen; successful treatment with folate should reduce the homocysteine level.)
If your low B12 doesn't respond to oral B12 doses then it's likely you have problems absorbing it.
If your blood shows IFAb then that's likely to be the issue for failing to absorb B12. Some people with IFAb are able to absorb oral B12 providing they swallow enough of it, but the exact process involved is unclear. The oral dosage has to be huge; typically a milligram per day.
Listen to your doctor. That should be the route to the answers!
Hi. It's me again. I was a bit quick responding there! You state that you have adequate Active B12 levels. I'm guessing that you've had that measured privately, and that's your choice but it won't tell you anything that a Total (Serum) B12 wouldn't, and that's available via the NHS at no extra cost. Speaking personally, if it was me, I'd be following my Full Blood Count for evidence, and comparing results over time. If the folate level has been low for a while then that would/should be reflected in your FBC, and that should respond quite quickly to folate replacement.
Thank you so much for all this information and that has really helped me understand things.Private testing and trying to figure it out alone is my only route sadly. As many in this forum and other autoimmune forums have reported trying to get any help from the NHS is like trying to get blood out of a stone. I can't even get my folate needs on the NHS as they only prescribe folic acid and not methylfolate and those with my autoimmune condition can't process the folic acid.
I only have my B12 tested as part of a full thyroid panel test that I have to do every few weeks so thankfully I am not paying anything to test it specifically.
My active B12 is showing as 89 (37.5-188)
When you say follow the full blood count for evidence what do I need to be looking at on this to help me unravel things?
Megaloblastic change in the FBC is reflected in a raised MCV and MCH, and some degree of anaemia is likely. The RDW indicates whether the situation is static or changing. If the RDW rises then something's going on. So, treat a deficiency of B12 or folate, the MCV will gradually fall, the RDW will rise more rapidly, and the MCH will reflect the MCV change. The Hb will rise slowly. In Iron deficiency, the MCV is reduced; on replacement, the MCV rises, and so does the RDW. The reticulocyte count, when performed, can also show the response within a few days.
Hi. Thanks for the response. My time is limitless once I get started on this sort of thing, so don't fret about that.
Not all systems report RDW; labs generate so many numbers that it's how much we put on the report; back in the days of printed paper, it was a struggle to fit it all on the sheet, so although I like the RDW personally, it's a personal thing.
Your results tell me that your MCHC is 34.5 [it's witchcraft.] That MCV range goes rather higher than I'd like; I'd prefer to see the upper limit more like 96, but there will be reasons.
The MCH is very sensitive. If it's been rising then that's a reflection of an underlying change, and your folate could be at the heart of this. However, we can see a rise in MCV & MCH in hypothyroid, but no-one seems to know quite why that is.
Like most things, fresher is better. A blood sample delayed before analysis is prone to give some odd results. The MCV is likely to be higher; the Potassium is likely to be higher. The folate can be skewed too. Samples sent through the mail are notorious. Samples collected by fingerprick are better than nothing, but sometimes not much better than nothing. A venous sample collected by a competent phlebotomist, using a large enough needle, [21 gauge or bigger], analysed without delay, [within a couple of hours, say] gives the best results.
I'm happy to be of some help, as are the many knowledgeable folks on here.
I am learning so very much through yourself (and your witchcraft ) TAHNK YOU.It takes my brain-fogged head so long to make sense of anything or I think I have understood something and then 5 minutes later I am all foggy again.
With that in mind, apologies if I repeat myself or ask the same thing several times!
Perhaps all the abnormal or elevated results from FBC will come right once my thyroid stabilises (or perhaps thyroid won't be able to stabilise until these have been addressed? All a bit chicken and egg).
I have held off taking any B12 supplements as I was worried that might mask some underlying problem but I am now wondering if I should just start and then see what happens with the B12 results on my next scheduled thyroid panel blood test. With the results I have would you think that might be a way to proceed as a first step?
Hiding behind my 'scientist, not medic' front, I would make an educated guess that any supplements should not affect your thyroid panel results. If your B12, folate and iron status gets settled down, then any thyroid-related variation in the FBC would be minor anyway.
Listen to your GP, but also give your GP feedback. That way we can learn from each other.
Good luck!
(The witchcraft is actually very simple. MCH=Hb/RBC. Hct =RBCxMCV. MCHC = Hb/Hct, so you can play with them. MCH/MCV =MCHC. Don't get bogged down with decimal places, mind!)
I think I worded that last query badly. The question was really about masking B12 problems if I started taking B12 without further investigations to discover what is really going on with my B12. The mention of the thyroid was only because I get B12 results as part of my full thyroid panel test anyway. Good B12 is essential for thyroid meds to work so it is included on the more comprehensive tests.
Taking oral B12 supplements should not interfere with further investigations. Here's a history lesson.
Once upon a time when we had the Schilling Tests, we had a functional test of B12 absorption. Before we could do the test, it was essential that the subject had been treated with B12 injections for some time, because as you know, B12 is needed everywhere, and the cells of the ileum also need B12. Deficiency of B12 becomes self-fulfilling, so the B12 deficient gut doesn't absorb as well as when it's B12 replete. On occasion, it was quite challenging to get a doctor to treat the patient before we could do the test. We also administered a B12 injection as part of the procedure. This was to saturate the transport proteins and avoid the radioactive B12 being utilised. Regrettably, we don't have that test any more, which is a shame.
If you need to get your B12 by injection then that's what you need. If megadose oral B12 can help you, then that's good. At least if your thyroid workup includes serum B12, that's one way of keeping an eye on it, but otherwise it's not needed.
Thank you SO much. You write so clearly that even my mulchy brain can make sense of it. Feel I have a little more in my knowledge bank now to do what is needed.
Content on HealthUnlocked does not replace the relationship between you and doctors or other healthcare professionals nor the advice you receive from them.
Never delay seeking advice or dialling emergency services because of something that you have read on HealthUnlocked.
) TAHNK YOU.It takes my brain-fogged head so long to make sense of anything or I think I have understood something and then 5 minutes later I am all foggy again. 
MMA and iFAB tests
Intrinsic factor antibody test
Difference between PA and B12 deficiency
MMA test - what does it tell you?
Intrinsic factor antibody test ranges?? 
