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Can too much B12 be a bad thing? - Pernicious Anaemi...
I’ve been self injecting B12 for about a year and a half now because I have terrible numbness, burning, pain and hypersensitivity in my feet and weak and off gait legs. I wanted to see if it were B12. I injected every other day until recently. Nothing has improved sadly. NHS hasn’t helped although I finally got a full MRI to check the spine for issues. None found.
I had a cardiac review this week for atrial fibrillation. Cardiologist saw my high B12 blood results and asked why. I told him. He did not like that I was self treating. He told me too much of any vitamin could be bad. I told him B12 was water soluble so I’d pee out excess but he was adamant that taking high doses, when not proven to need them, is a bad idea.
What do you think about this sort of reaction?
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FancyPants54
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Amusing. I would have told him that as a cardiologist, he should stick to cardiology and not be adamant about things he does not understand like nutrition science.
It's true that many vitamins can be toxic in excess (like we see with the Vitamin A poisonings in Texas thanks to the genius of RFJ Jr) : yahoo.com/news/texas-childr... but this toxicity is a rule of thumb and there are many exceptions, B12 being one.
In relation to your persistent issues, there are many possibilities. It depends a lot on how long you were B12 deficient. Untreated neurological issues may persist despite treatment if they were there for some years. I'm assuming that things like folate, ferritin/iron are at good levels?
The other possibility is that the persistent neurological issues are not B12 related. Too many possible causes of neurological issues for me to attempt an amateur diagnosis.
Funnily enough he mentioned vitamin A, to which I said I know vitamin A is toxic. I'm not taking vitamin A. I also told him I was taking Levothyroxine WITH natural desiccated thyroid extract Armour Thyroid. That was so far outside his universe he ignored that completely. This letter to the GP just said I was on Levothyroxine. I expected a fight over that. Not B12.
I suspect my issues are not B12 related now. And it looks like spinal compression is ruled out. So need to see a nerve specialist next I think. The cardiologist said I probably had sleep apnea because I don't wake up refreshed. I wake in the night because of the awful pain in my feet! And I'm not refreshed because I can't work out how to take a large enough dose of thyroid hormone to stop me being hypo. But as he'd just quoted my September 24 thyroid TSH test as being "fine" because it was 2, when in fact it was over 4 (bad) meant I just kept quiet. My iron components are OK, but I struggle to keep them OK and can never seem to get them optimal. I have to supplement them nearly all the time. Blood test for the iron panel is due in the next week.
Since I reside in the USA additional background since this there is more to the story as to why this was done. The decision to offer a vaccine option was based on the fact the World Health Organization has administered vitamin A in Africa to reduce mortality during measles outbreaks. This is a strategy in a part of the world with widespread malnourishment, and vitamin A deficiency, compromises the immune system.
Is there malnourishment in Texas? Yes. Predominantly in impoverished areas where migrant families come over from South of the Border. Culturally these families are pro-herbal remedies and reluctant / skeptical of modern medicine, hence, these children aren't vaccinated for anything.
RFK, Jr. made the recommendation based on the WHO work in Africa in an effort to offer an option for communities who will not get a vaccine which pre-dates RFK, Jr. in his role. RFK, Jr. went on to advise these communities to do so (Vitamin A) under the supervision of their doctor or community care giver.
Not all is as bad as the media portrays. After all, RFK, Jr. is a Democrat who happened to be appointed by a Republican. It is refreshing to have more balance in our political system.
I was also old by an internal specialist to stop injecting and he even doubted I had pernicious anemia. Even though 2 different labs had confirmed it. Sorry….. I really lost faith in the doctors who are supposed to be specialists…. B12 helped me regain my life again, physically and mentally. I’m now working again and lead an active full life.
I don’t know if u have other medical conditions but all I know is that so many health professionals have no clue about b12 deficiency and can cause more harm than good by saying things like that. If I had not injected as much as I did and stuck to the programme - I would not be where I am now.
Glad to hear you are back to work and doing so well.
Some years ago, I managed to get a phased return to my full-time job after being off sick for over a year - but only got as far as two days a week. It was a struggle, and I was quite relieved to get accepted for voluntary redundancy after the Covid pandemic.
If two labs confirm PA, that should be sufficient information for any follow-on specialists. Getting a PA diagnosis is difficult enough once, given that the IFab test will give only 40-60% of those with PA a positive result ! Since an IFab positive is 95% accurate for PA, that should surely be accepted the first time.
An alternative opinion should not be required if you have twice been diagnosed with PA and have returned to your life now, due to successful B12 treatment. What further evidence is there ?
Difficult to get back there, difficult to stay there ..... nigh on impossible if also having to fight your corner continually. Well done.
Yes, he'd just told me I have heart failure so I was in shock. Years ago, at the start of my atrial fibrillation journey, another cardiologist told me the small amount of T3 I was taking with my Levothyroxine at the time would kill me.
Fortunately I have learned enough about thyroid to know what utter nonsense that was. You are right, I have no way back to him to ask questions. Signed off now with a diagnosis and a recommendation to the medication he wants me on and if the GP wants me to see him again we have to go back to the start and ask for a referral.
I didn't know that about B6. Thank you. I have been taking a B Complex with the B12 injections to keep other B's in sync. Should I leave that off rather than taking one a day all the time do you think?
It depends on the dose in the B complex. National Upper limits vary - the EU recommends 25mg, I believe, which is on the low side.
You could ask a pharmacist what they recommend (and let them know if you are on any other medications as they should know if there are any interactions) - and that would apply to all supplementation.
Everyone should print the following off and take it with them when on an appointment and ask for it to be circulated among all the medical staff so as to put to bed the lie that it is toxic. One could also ask what would they do if someone was brought into the surgery suffering smoke inhalation.
1. The Usual B12 Dose for Deficiency
For B12 deficiency (especially in the UK), the typical treatment is hydroxocobalamin 1,000 micrograms (1 mg), given intramuscularly (injection), often every 2–3 months for maintenance after a loading phase (usually six injections over two weeks).
2. B12 Dose for Cyanide Poisoning
Now, here’s where it gets wild — for cyanide poisoning, doctors give hydroxocobalamin 5 grams (that’s 5,000,000 micrograms), given intravenously (into a vein), not just intramuscularly, and often repeated once if needed (another 5 g).
3. How Much Higher is That?
Let’s do the maths. The normal B12 deficiency dose is 1,000 micrograms. The cyanide poisoning dose is 5,000,000 micrograms. That’s:
5,000,000 ÷ 1,000 = 5,000 times higher
So it’s 500,000% higher than the dose used for treating B12 deficiency.
4. Why So Much?
Cyanide is rapidly lethal because it stops your cells from using oxygen, like suffocating from the inside. Hydroxocobalamin acts as a cyanide binder. It grabs hold of the cyanide and forms cyanocobalamin (which your body can safely excrete in urine). This reaction is fast and potentially life-saving.
You need masses of hydroxocobalamin to mop up the cyanide in the bloodstream before it damages organs — hence the mega-dose.
5. How is It Given?
It is given via IV infusion, not injection into the muscle. This is usually done in a hospital or emergency setting. The infusion takes place over 15 minutes to 2 hours, depending on the severity.
I guess the determined physician could say "yes but that's just one mega dose, not daily doses building up". But it still makes a mockery of their hypothesis.
That’s a common argument — that one mega-dose for cyanide poisoning is acceptable because it’s a single event, whereas regular dosing could lead to accumulation. However, this concern doesn’t align with what we know about B12 pharmacology.
Hydroxocobalamin is used in cyanide poisoning at doses of 5,000,000 micrograms — that’s 5,000 times higher than the standard 1,000 microgram dose used in B12 deficiency. Despite the scale, it’s considered extremely safe, and can be repeated if needed, even in emergency settings.
Vitamin B12 is water-soluble, with excess excreted via the kidneys. The body has limited capacity to store B12 beyond what’s needed, particularly when absorption pathways are impaired. There is no robust clinical evidence that frequent dosing in deficient patients leads to toxicity.
In fact, symptom resolution — particularly with neurological involvement — often requires sustained, frequent dosing, not limited or spaced-out injections. So the idea that B12 “builds up” dangerously through regular treatment isn’t supported by evidence or clinical outcomes.
I'm so glad it worked for you. When did you first notice improvements starting to happen? I've been using B12, EOD for over a year and slightly less than EOD for about 5 months now. No sign of improvement that I know of.
Persisting with my self treatment well into my second year, I remember asking myself if I may have permanent peripheral neuropathy as I was not experiencing significant improvement.
It was not until I was approaching my third year that I noticed some slight improvement. It’s very difficult to focus on anything other than the pain and daily struggles of life in general.
This was a very long time to notice significant changes but I had to consider how many years I was suffering prior to me connecting the dots that I accepted that I needed many years to return to normal again.
During this time I had seen rheumatologists, haematologists and neurologists and not one doctor connected all my symptoms to pernicious anaemia, I had made the connections by my own research (that’s when I discovered the Pernicious Anaemia Society, purchased the relevant books and learnt all I could about PA)
Knowledge was the guidance I needed, which significantly eased my anxiety that my symptoms were genuine and helped explain what was causing all of my problems.
With time and patience and feeling reassured that I was doing enough for my body to heal, I finally and gradually was experiencing some relief from the constant pain.
Others may not have needed so much time to heal like myself as everyone is different but in hindsight, I now understand that there is so much going on in relation to B12, it’s justifiable that the body will respond the way it needs to. I’m just so grateful with my positive outcome today.
Be patient with yourself and allow your body as much time as possible to navigate through this difficult time, you too will experience positive results with time and perserverance.
The trouble is I don't have a diagnosis. My Active B12 results were in the middle. Serum hovering around 4-500. It was a case of lets try this and see if it helps. So far it hasn't. But if it's not harming me either, then I will carry on for now anyway.
Even if you don’t have a confirmed diagnosis, there a few things you need to consider.
First and foremost, what are your symptoms?
Secondly, and something I’ve learned from my own personal experience, is your serum B12, which is considered by medical experts to be in range. I too had a serum B12 of 450-550. I was receiving three monthly B12 injections but, I was highly symptomatic, I was so unwell.
My levels were like yours, considered ‘normal and in range’ but I knew I was not feeling normal.
Along my journey, I had a gastroscopy and a biopsy which confirmed pernicious anaemia. Before this I only tested positive for parietal cell antibodies and negative for intrinsic antibodies.
Some professionals consider a positive parietal antibody test sufficient confirmation of pernicious anaemia and some consider the intrinsic antibody test a positive confirmation of pernicious anaemia, for which less than 30-50% of people test positive for this.
So technically, your symptoms and a gastric biopsy are the best gauge for confirmation of pernicious anaemia.
My current serum B12 levels are over 2000 (which is not a true indicator of your B12 levels)
You must follow the active B12 (or the holotranscobalamin test) and MMA and homocysteine levels test. These are highly indicative of whether your B12 is working at a cellular level.
These tests are highly specialised and not all pathology companies provide this test, it’s most likely a private clinical test.
I highly suggest you go by your symptoms and go by the extended tests above for a confirmed diagnosis.
Once you receive a diagnosis don’t assume mainstream medicine will be completely supportive, as I had the above diagnosis and tests and the protocol was one injection every three months.
One injection every three months WAS NOT sufficient for me and I was still highly symptomatic.
It was only when I took control of my own treatment with daily methylcobalamin B12 and three years later I began to experience relief.
This was such a very long time but, in reflection I am so grateful that I persisted with my self treatment. Now I only need to self inject once a week and my symptoms are kept at bay.
Allow your body to heal at its own pace and in time you will also succeed.
Don’t allow any doctor to gaslight you with misinformation that too much B12 is toxic and will cause more harm than good. This is not the case.
Stay strong and positive and you too will overcome all your symptoms and will eventually experience peace and good health.
Keep us posted with your journey as it helps to communicate with people who understand what you’re going through and this forum is a lifesaver when all seems lost.
There are water - soluble vitamins that can be overdosed . But not water soluble B12 . If a consultant is unaware of this fact, it is worrying .
I am left with painful irreversible neurological issues with my feet , because of long delayed treatment of Pernicious Anaemia ( positive Intrinsic Factor Antibodies test) . It is maddening to think that it could have been avoided with timely injections of the cheap vitamin B12 .
specifically with B12. I took three times the recommended dose of Solgar 1000 mcg in the space of a week. Since then, my B12 has become very elevated and cannot bring the levels down.
I can't remember off the top of my head and finding it would be quite difficult because I file all my results with thyroid test results as the priority so the rest might be out of sync. But I tended to be around 400-500 serum. I know that below 500 the PA world considers it deficient but GPs think its just fine.
Try 50 mg of P5P form of b6. Make sure it's that form as other forms in that dose are toxic.
Try that for 3-4 months to see if there is any change.
If not start trying to high dose b1; however, this is VERY tricky as it will deplete other minerals if not done properly; thus you should follow the guide here for this:
Elliot derives his information on b1 protocols from Dr. Derrick Lonsdale and Dr. Chandler Marrs
For others reading this, my recommendation is to try 1 thing at a time. Don't mix multiple remedies or it confounds causation of solutions or issues that arise.
I recently got a very similar response from my cardiologist when I mentioned B12: "People see things about supplements on TV, etc, etc." I described to him the relationship between B12 deficiency and homocysteine, and the relationship between homocysteine and inflammation, including vascular inflammation, and the correlation between vascular inflammation and high blood pressure. I described how my blood pressure rose to 150 and 155, coinciding with symptoms of B12 deficiency, and how, after two years of daily B12 injections, symptoms of inflammation, including high blood pressure, were mostly resolved. Cardiologists especially should be aware of issues corresponding with hyperhomocysteine, eg,
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Can someone translate what tests will be done please?
