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Pernicious Anaemia Society
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Mental Problems/Paranoia/ memory problems and more due to low B-12?

I had really low B12 issues at one time (from fasting) ..it is a really long story, but honestly I have been diagnosed with mental health problems and wonder irreversible B12 damage is the problem (I am not sure, but some literature says this but PAS site says curable......the QUESTION IS....are my problems related to nerve damage and still low B-12?.....I have been diagnosed with having psychosis- hallucination and delusions....I have a hard time focusing and concentrating when learning a task....symptoms seem to be a little better if I get an injection but then goes away. I also get irritated really easy/angry easy and too much stress I literally feel mentally sick!!....I am nor sure what to do.....I have had again atleast 100 injection sub-cutaneously and taken Methyl B-12 supplements for a long time--atleast 5 years.....I had other vitamin deficiencies but up until 27 (that is considered too late for onset of schizophrenia)....sorry, this post might be not normal and probably weird, but honestly all my symptoms point to low B-12....my memory is so bad sometimes I think I have early dementia....it is known that B-12 can cause psychosis....si maybe that is not unusual to hear on here...I have no idea.....PleaseHelp!! if you can!

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Hi. Have you been medically diagnosed with b12 deficiency? Still learning myself but lots of help on here. You sound a little panic stricken I hope you are ok. Please don't worry you will get lots of help tomorrow it's late.

OK...I actually this found this site in the US (Pacifac side of US in fact, so even farther).

I actually started doing supplements before I was tested!!....(bad) but I did do homocysteine testing very early on and my Homocysteine was high but came down after starting methyl folate and methyl B-12. I do get my B-12 checked but it always comes back high. The only reason I know that I had B-12 issues is because I became very depressed and anti-depressants were not working....They tested me for Methylation issues and a gene polymorphism called mthfr (methyl-tetra-hydra-folate-reductase) that actually is an enzyme that cannot break down Folate but B-12 is harder to absorb too...and well as vitamin B-6.....I have to take Methyl B-12, Methyl-Folate and B-6 along with probiotics to feel sort of normal. I am doing acupuncture and well......I really do not know what was the begginning factor honestly.

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Thank you very much, I appreciate the response.

Please note that a number of responses on this thread have been removed as they were off topic.

This forum is a place to share personal experiences and support others in obtaining appropriate treatment for B12 absorption problems, particularly Pernicious Anaemia, though given the problems with specifically diagnosing PA as the cause of an absorption problem a formal diagnosis of PA as the absorption problem is not a requirement.

For the record MTHFR is a gene everyone has. Some variants of these gene affect the enzyme produced in such a way that the methylation of folate becomes less efficient with a knock on effect on processes that need methylfolate.

The MTHFR gene provides instructions for making an enzyme called methylenetetrahydrofolate reductase. This enzyme plays a role in processing amino acids, the building blocks of proteins. Methylenetetrahydrofolate reductase is important for a chemical reaction involving forms of the vitamin folate (also called vitamin B9). Specifically, this enzyme converts a molecule called 5,10-methylenetetrahydrofolate to a molecule called 5-methyltetrahydrofolate. This reaction is required for the multistep process that converts the amino acid homocysteine to another amino acid, methionine. The body uses methionine to make proteins and other important compounds.


I think this has happened to my brother, so sorry I can't say for sure but it does sound like that and he mysteriously seems to blame me for something and we were once so close. He won't see doctor. Obviously I don't know for sure but I did ask a Dr online and he said it could happen. He manages on his own (he has M.S) but he won't see me now. I used to give him the Methylcobalamin jabs.

They say that you should also take a good quality b complex and not take only some of the B's vitamin , I wonder if getting enough vit D will also help, are you in a sunny place. Good quality fish oil like Krill is great for omega threes which are essential for brain health.

As you are so prepared to try everything it sounds like you can get better from what I have read. At least there is no harm in large doses of b12. Keep your spirits up and you will get there.

If you read up on the Internet there is lots of YouTube films with advice which I guess you already know. Seasidesuzie on the thyroid side of this forum has great nutritional advice.

Good luck 😎X

Note: edited by admin to remove name of doctor

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wow....I have similar symptoms to your brother.

My recurring b12 deficiency symptom was suddenly becoming semi conscious then tinnitus followed by auditory hallucinations with a sense of euphoria then a state of severe confusion. Episodes lasted around ten seconds and confusion took about 5/10 minutes to abate. I would get the symptoms around week six after my injection and they would last for around seven days. They stopped after about two years.

I told a specialist about these symptoms and immediately she began going down the mental illness route.

The problem lies, in my opinion, with doctors reacting to symptoms then jumping to conclusions about causes. Every doctor and nurse that I have discussed my b12 deficiency with has immediately switched off and tried to take it down another route.

At my last injection, two weeks ago, I raised the issue of the fleeting pins and needles I was experiencing - all over my face, arms legs etc. The nurse immediately asked how many units of alcohol I drank even though pins and needles are a very common symptom of b12 deficiency.

b12d.org is website which relates simply to b12 deficiency - a condition in its own right with symptoms which relate to the damage done to the myelin sheath and the symptoms arising from this. There is a whole section in mental issues.

Good luck

Note: edited to remove name of medical practitioner


thank you....I appreciate this.

Confusedonmyproblem B12 deficiency is not caused by fasting. Levels are regulated by stores in your liver meaning that B12 levels are actually not very responsive to changes in dietary intake - and a dietary deficiency usually takes year, if not decades to manifest.

The symptoms of B12 deficiency are similar to those of folate deficiency which comes on much more quickly.

The fact that you have problems processing folate may affect your ability to process B12 but its actually quite a small effect.

There are a large number of processes in cells that need the presence of B12 to operate properly which means there are a large number of genetic variants that can cause these processes to run less efficiently and mean that a given individual may need higher levels for those process to run properly - which is likely to be one explanation of the huge variation in normal range for serum B12. Strictly speaking genetics of processing B12 is off topic for this forum which is about B12 absorption problems - the most common one, PA, specifically.


High serum B12 levels can cause problems in some individuals - leading to a functional B12 deficiency - lots in your blood but something affecting the efficiency with which it gets into your cells. Easiest solution is to raise levels higher if this happens, eg as a reaction to injections.

Gambit62 That is very interesting because it describes exactly what I experience. Many spources say you can't take too much B12 but that's not my experience.

When I take a lot of B12 (such Img hydroxoB12 by injection daily for a month or two) I will see many B12 deficiency symptoms flare up. When this happened in the past, I would take even more B12 and my symptoms would get even worse It became a vicous circle, until I realised what was happening.

I'm currently restarting my injections and would truly welcome any signposting to where I can learn more about this functional B12 deficiency.

Is it perhaps connected to to the idea of functional folate deficiency as found in what some people call "methyl trap"?

I don't think that is true if you fasted over a 100 days in year and fasted a lot the prior 2 years.... and B-12 is important a psychiatrist said B-12 is extremely important in mental health issues....I am not going to argue anymore...I don't know I don't feel right and somewhere along the line I read that psychosis/hallucinations and delusions can be based by low b-12.....if it is not low b-12 than I am not sure what it is....I was basically in Cult and was indirectly forced to fast...I'm the idiot anyway... should have never listened to the guy....I had other nutrient deficiencies as well....but I think those are fixed.....I might have a lot of toxins in my body still...not sure....thanks for the help.

Note minor admin edit

fasting will not cause a B12 deficiency - even 100 days is unlikely to be sufficient even if it was done as a continuous period to produce a dietary deficiency - it takes years for vegans to develop deficiencies.

Fasting could make an absorption problem manifest quicker.

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methylation and MTHFR isn't the only process that involves B12 that would lead to susceptibility to mental health problems. B12 is involved as a methyl donor in the COMT process - regulated by a totally different gene. This process recycles neurotransmitters and it is a process that needs to run in a balanced way - too fast and it causes problems - too slow and it causes problem. No doubt there are also other processes/genes that can be involved. There also appear to be variants on the COMT gene that don't respond well to use of methylB12 and there may well be other genes where the same is true

thank you...you seem to be knowledgable in genetics....there is so much to genetics and nutrients to heal genetic weaknesses....an ever awaking field.

why would genetics be off topic, if it was part of the problem that caused Pernicious Anemia...I don't understand that at all....obviously absorption issues because of intrinsic factor and low pepsin/ hydrochloric acid would be top priority, but if genetics is part of the issue for that individual it needs to be explored.....couldn't that be a reason someone might have pernicious anemia?

the genetics of the metabolism of B12 once absorbed through the gut - which is where this is going - are off topic because they aren't actually involved in PA.

You are correct that PA itself does have a genetic component but so far to my knowledge nobody has actually identified any specific genes that lead to PA - just that it runs in families. Yes, it would be useful to know what genes are involved and what triggers them as they are obviously latent and that would be on topic.

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Confusedonmyproblem I think most metabolic problems of the brain could, if severe enough, cause brain malfunctioning and create all sort of symptoms including dementia or psychosis. It's important to checked over by your GP for all other possible causes. I have seen people follow up their own theories and years later find it was due to something else obvious all along if only they had noticed it.

That said, I need B12 and I have experienced dementia-like states which can last weeks and distinct dissociation or psychosis which lasts hours and responds quickly to folate. It is surpisingly strong, the thoughts are very strange and it improves quickly if you take the right supplements. Even if you have the same symptoms, it does not mean you and I share the same cause.

A few researchers call this "folate psychosis", others call it "homocysteine psychosis".

Take care with personal conclusions -- the fact you have such a condition and the fact that you may be B12 deficient, does not show once caused the other.


I found that high folatecreally lowered my homocysteine levels and yes high homocysteine is very toxic to the brain.....that would be great if it was folate but that is the other vitamin I have taken a lot over the past 10 years.....folate is easier to get the levels up.....B12 is actually inside the myelin and helps nerve conduction as you all probably know.....I think my folate levels should be fine.....I do have dementia like symptoms...does anyone else get angry easy now?...I am actually higher strung to want to argue.....thank you this was great information.

Did you supplement folate or folic acid?

yes in America, they can prescribe "Deplin"....it can help.....I take much lower levels now as 15 mg is now too strong....thank you.

It’s interesting to see that fasting is not considered a way to have low B12. If there is already autoimmune B12 deficiency present but not diagnosed then the liver would already be losing stores of B12. Severe fasting can cause those levels to fall even further. Consequently symptoms will worsen. I know it through personal experience. I also know the horror of psychosis (that is increasingly looking like it was caused by B12 deficiency) and the awful failure of health service personnel.

If anyone suspects they have B12 deficiencies and are also experiencing neurological or psychological difficulties then understanding that your body is under a lot of strain as well as your mind is important. You can always try a sublingual mythlcobalamin B12 supplements to see if it helps. (At one point after diagnosis with PA I had to take high doses of mythlcobalamin B12 to support my healing.)

Getting good B complex as well as iron might be important to your health or may not. But everyone is different and its a try and see situation for sure. I have to have iron everyday and B6 and B complex regularly. Have you checked to see if you need these?

To offer some hope I have recovered from psychosis but I have recently become aware that confusion and memory problems can be caused by many physical diseases not just psychological ones. Doctors that do not do a differential diagnosis to rule out causes of psychosis that are treatable by medication for physical or medical illnesses are, to say the least unhelpful (I would actually use stronger words here). Request a differential diagnosis because treatment via mental health services which are under strain would cause risk if the underlying cause is a physical illness. Patient disability through failure to diagnose correctly is not unknown so be as polite as you can but firm if you suspect PA. Difficult to do, I know, but have confidence that it doesn’t hurt to ask for a differential (and if it is refused then ask why).


Thank you... I really appreciate this.....yes I think my body is still under a lot of strain.....I have tried tons of things....HBOT, detoxing, intervaneous vitamin therapy, over 100 methyl B-12 injections, I still take a ton of vitamins just to feel sort of smart but my memory is broke...my mind is broke...I recently started high amounts of probiotics and fermented foods...many more things but I can't remember off the top my head....thank you

Your most welcome! And I truly hope things improve for you soon. I know it’s tough going but its possible to pull through. Good information is extremely helpful to help yourself understand what might be going on. But keep in mind B12 deficiency may not be the only cause or as said earlier the wrong type of B12 is not helping.

I think any of the autoimmune diseases take a while to understand first that they are present, second how to help yourself heal, and then third how to manage day to day. Frequently it’s forgotten that a simple infection can suddenly make the body need more support and so the old idea you take a certain amount of xyz (insert here whatever works for you) is probably not the way forward. It’s more like diabetes or high blood pressure and needing to be aware of daily changes.

Again best of luck. Do what you can to ensure a psychiatric diagnosis isn’t given in place of a medical one so you avoid unnecessary problems. For instance I am now facing discrimination at a medical hospital for heart and lung issues which have been noted on medical images but the first route doctors take is I’m imagining it all because PA presented with psychosis first (had symptoms for years before but failed to complain as I thought I was just stressed out and more feeble than others :-( ).

thank you for care.....and wow, I am sorry....sometimes doctors just do stupid things....I its irritating.

Yes, the information would be more complete if it included fasting....that is common sense, not getting the vitamin at all is definitely a reason for low levels.

Have you taken only methyl b12 all along?

Methyl b12 makes me feel very bad. Almost like I'm having deficiency symptoms. Kind of wired, on edge, paranoid, among other things. The last time I had a methyl shot it was given by mistake and I figured it out because for several days I felt poisoned inside after the injection.

It took me a while to get things so I was feeling at least decent most of the time. For me, it takes a cyanocobalamin injection a few times a week and a good B complex most days. The B complex I take has a small amount of methylcobalamin and adenosylcobalamin. The small amount of methyl doesn't bother me and it's good to get different forms of B12 I've heard.

I'm not a Dr but id suggest switching to cyanocobalamin injections for a while to see if you feel better. The MTHFR stuff is useful information. But I started out with methyl because of the MTHFR stuff and I really felt quite unwell with much of it so having a polymorphism does not mean your body requires the methylated forms necessarily.


I've had only "1" Hydroxoconalmin....and yes it was the most beneficial...sadly the doctor switched up back to cyanocobalmin which were not as effective....I ended up moving. I need to find doctor in my area that does hydroxycobalmin.....I do use hydroxy lozenges the most and I guess the hydroxy type has some type of anti-oxidant ability.

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