Pernicious Anaemia Society
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Alzeimers and B12

Hello, this may be a long shot....

My mum has been diagnosed with Alzeimers. She is 72. I knew my mother had an underactive thyroid and wondered if maybe, just maybe, she had been misdiagnosed, so asked my dad if she'd ever had her B12 tested.

A quick flick through her recent bloodtests, I did note that her b12 was 266 (211-911), her thyroid was 3 (0.35-5.5) and her FT4 was 17 (10-19.8). I can't remember any other results as my mind was in a spin at the time.

Is it remotely possible that her low B12 could be the problem rather than the Alzeimers diagnosis or even possibly too low a dosage of Levo? Apparently she has been seen by the 'mind people' who, having asked her a series of questions, confirmed Alzeimers. She can't remember when she was born, my dads birthday, forgets news items that she sees on the lunchtime news and sees the 5 o'clock news as breaking news (hope that makes sense).

I'm probably clutching at straws but if maybe her B12 / Thyroid was really the cause, I'd rather suggest it to them than let her deteriorate further. I know it wouldn't cure her or fix the bits that are already broken but if it could possibly stop / slow further damage I would feel I did what I could to help.

I'm going to copy this post onto the PA and Thyroid groups.

Thank you for any advice you may have x

17 Replies

Has your mother been specifically diagnosed with alzheimers or has she been diagnosed with a dementia. Alzheimers is a specific type of dementia and the nature of the damage is different from that that would be seen in a B12 deficiency.

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My dad said Alzeimers 🙁 I guess that doesn't sound promising.


suggest that you find out specifically if you can as the two do get used interchangeably though they are obviously very different.

The real downside will be how long the problem has been going on if it is a misdiagnosed B12 Deficiency is that if it has been going on too long then the damage may be permanent anyway.

Dementia in someone you are close to is never an easy thing to cope with.

Proper diagnosis would, as I understand it, involve brain scans so doesn't sound as if that has really been done.

you may find this sight useful

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Thank you Gambit62 .... now you mention it, I remember my dad did say she'd had an MRI. It all came as a bit of a shock so I can't remember everything he said, but it does all sound quite definite now. Thank you for the link, which I'd visited beforehand.

Thank you again, I was just hoping that maybe they'd got it all wrong.

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I do note that several other medical/research sites mention Alzheimer's and B12 possible misdiagnoses. My father (who sadly died today) was diagnosed a four years ago with Alzheimer's and he had had it for years. He didn't seem to follow the normal pattern for this disease and it always puzzled me. His diet, symptoms and lifestyle, seemed to suggest more that it may have been a B12 deficiency and this may be more common than people know. It is a great tragedy to think he may have been able to have some reversal of symptoms and I am angry with myself for not considering this possibility.


I am sorry to hear about your loss - losing a parent is very difficult, and anger is part of the process. My grandfather died as a result of vascular dementia and my mother has significant cognitive decline and both were on metformin for years so I can't help suspecting that B12 deficiency was a factor - my mother is now on B12 treatment. My grandmother died a few years ago after a stroke and cognitive decline that included significant depression and symptoms that for me now point to B12 deficiency - which is more likely than not at 96. At the relevant times I wasn't aware of B12 deficiency at all. Being angry with yourself is a natural response but isn't a rational response. Even if you had considered it there is always the possibility that it wouldn't have been B12 ... and even if it was getting anyone to look at it could have been really difficult to get anyone to listen. There are two many what ifs in all of this to be cross with yourself.

Hope that you have someone you can talk to about the good times with your father before the dementia - you need to remember him as he was when he was well.

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I am so sad to hear your dad passed away today. I too am angry that our system does not shout louder about the possible links between B12 & alzeimers. I gave my dad all of the information here plus a tonne more from elsewhere that I found elsewhere from places like the BMJ re homocysteine, B12, etc... I hoped that he would at least ask for injections or buy the B12 / B Complex for my mum in the desperate hope that maybe, just maybe it would make a difference to her. However their GP said it would mess up my mums thyroid meds (which is so untrue), so they have decided not to bother. I can't do anymore, as they will not listen to me. BuT...I am doing my best to spread the word and stop others being fobbed off.

Sending you a virtual HUG xx

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There's a book I found helpful "Could it Be B12" by Sally pacholok and JJ. Stuart.

Chapter 2 mentions dementia type symptoms can be caused by b12 deficiency. Has various case histories.


Thank you Sleepybunny . I will try and get hold of it x

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Hi Janey

I am not medically qualified but I will give you my experience of alzheimers and low B12.

My father was diagnosed with Alzheimer's Six years ago he also has an under active thyroid

We did notice his memory being poor after his first knee replacement and then noticed a sharp decline after his second knee replacement two years later. I am firmly convinced that the nitrous oxide severely depleted his B12 and that he was mis diagnosed

There is evidence now that surgeons know about these effects and try to operate using an epidural

My father is now on B 12 and although he is still slightly confused but he has not become any worse

By the way he is 88 and lives with me. I still think he needs more frequent injections but you know what it's like

By the way I have PA and thanks to the info on this site have been self injecting for the past eighteen months and feel loads better

Sorry to hear about your Mum it is a horrible disease but there is hope


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Hello Barb

I an sorry to hear about your dad. May I ask, is he getting injections because his b12 was below range or because it was low (in range) but because of symptoms?


My relative has been diagnosed with (early) Alzheimers after a brain scan. But symptoms are very extreme and worsening daily.

Also had lifelong thyroid issues, but untreated since an op years ago. Other auto immune illnesses. Also a likely candidate for B12 Def / PA - not only all the symptoms, but ticks every single box for causes.

Could I get anywhere with her GP on this? No. Of course I couldn't.

Already a long way down the path of anti depressants, sleeping tablets, painkillers long term: ie mental health.

I think it must be possible to have both PA and Alzheimers. But then the PA symptoms would be said to be due to the Alzheimers, and therefore remain untreated, which is what I believe has happened in my relative's case and might account for their rapid deterioration.

This area of medicine needs looking at URGENTLY.

The current trend to go for Virgin operated drop in centres with no continuity of care will not work.

These illnesses are utterly tragic for the person themselves and also for everyone around them - from family, to community, to use of medical resources. I speak from experience.


Thank you. It really is tragic. Having joined this group a few months back with my own B12 issues I am more than aware of GP ignorance (and ours) on the subject.

My mum apparently started medication for her condition last week and my dad wants to wait 4 weeks for those meds to kick in before considering other options.

I thought that maybe he should discuss the possibilty of her low B12 with the docs and see whether or not injections might give her some relief, stop the progress or at least slow it down. I know it wouldn't fix, cure or reverse what's already damaged. I hate the thought that not everything is being considered and ruled out. :-(

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"I thought that maybe he should discuss the possibilty of her low B12 with the docs"

I have in the past written letters to GPs when I wanted to query something. I certainly wrote politely to ask if b12 deficiency might be an issue.

What I didn't do when I wrote these letters was to include quotes from relevant UK B12 documents. If I have to write one now I mention

1) BCSH Cobalamin and Folate Guidelines Click on Diagnosis of B12 and Folate Deficiency

2) I also use the summary fbirder compiled. See last link in list in third pinned post. Link also on his profile page.

Someone I know has dementia and I suspect that B12 deficiency is a possibility in their case. I have read that people with dementia may experience increased symptoms if they have a UTI (Urinary Tract Infection)

bjhealing51 mentioned the effects of nitrous oxide.

I am not a medic just a person who has struggled to get a diagnosis

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Thank you. I am going to put all of your experiences, links and book advice together for my dad to see if we can push for further investigations, asap.

Thank you again x



I can't remember whether you joined the PAS. Perhaps it might be worth talking to them about your mum.


PAS tel no +44 (0)1656 769 717

Apologies If I have already mentioned the following.....

Have you got copies of "full blood count", ferritin and folate results for your mum as well as the B12? There can be useful clues on the full blood count(FBC) as to whether B12 defic or folate defic or iron defic is a possibility.

Low iron can lead to microcytosis (small red blood cells). Low b12 or low folate can lead to macrocytosis (enlarged red blood cells). A person who has both low iron and low B12 and/or low folate may appear to have a normal MCV on the FBC because the effects of iron deficiency can mask the effects of low B12 and/or low folate.

Has your mum ever had an IFA (intrinsic Factor Antibody test)? This can help to diagnose PA but is not always reliable. A person can still have PA even if IFA test is negative.

BCSH Cobalamin and Folate guidelines mention Antibody Negative PA. Three quarters of the way through BCSH Cobalamin and Folate guidelines is a flowchart that shows the process UK doctors should follow with someone who has low B12 or is symptomatic for B12 deficiency. link to BCSh guidelines in my post above.

Causes of B12 deficiency

Is it possible that any of these apply to your mum? Some medications can interfere with levels of B12 and folate in the body.

Symptoms of b12 deficiency

pernicious-anaemia-society.... Click on Symptoms Checklist

People at risk of PA


The article above mentions that some people develop PA as they get older due to age related gastric atrophy. It also mentions that PA can run in families. Do you have any blood relatives with PA or other autoimmune conditions. Has your mum ever had a test for Coeliac disease?

Another B12 book

"What You Need to Know About Pernicious Anaemia and Vitamin B12 Deficiency" by Martyn hooper

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Sleepybunny you have gone above and beyond any advice, etc that I could have asked for. I am goingto see if I can find other blood test results that might provide clues. Thank you so much for all of the questions and links above. Only today I have been for my own IF test so that result will be interesting. This community is amazing....I feel terribly sad for those out there suffering unneccessarily with no knowledge of this site and its wealth of info.

Thank you again xx


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