Low stomach acid DUE TO b12 deficiency - Pernicious Anaemi...

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Low stomach acid DUE TO b12 deficiency


While we commonly hear that low stomach acid can cause b12 deficiency, what I hear less about is that having a b12 deficiency being able low stomach acid. What is everybody's thought on this? It's somewhat of a chicken vs egg thing here.

As for me being a long time strict vegan (and doubt PA sufferer), I believe it's possible that after years of no reliable source of b12, I became deficient. After years of being b12 deficient, my body became unable to create adequate amounts of stomach acid which has hampered my digestion causing bloating and digestion issues.

I'm hoping that after long term b12 supplementation, my stomach acid levels will rise and improve my digestion.

Has anybody seen any evidence of low b12 causing low stomach acid and having treatment reverse the low acid?

Thank you for any input

11 Replies

Neurological damage to the vagus nerve from B12D, causes the parietal cells in the stomach to produce both less acid and less intrinsic factor.

You can eat more acidic foods such as salsa, orange juice, vinegar, tomatoes to increase your stomach acid.

But nothing at the moment will increase the intrinsic factor that is specific to your ileum. Hence the B12D. Porcine IF is being tried by some people. I have no experience with this.

The B12D and nerve damage is a downward spiral which is the pernicious “deadly” portion to the condition .

Get on B12 injections and folic acid supplements and a daily multivitamin to stop the neurological damage to your vagus nerve and all your nerves. Healing of nerve damage is very slow if at all possible.

I don’t suppose not being a vegan is an option.

Take methyl sublinguals as well. Get your blood tested and you want results to be high >1500 pg/ml to support repair of nerve damage.


Thank you for your answer - you have great insight into this. It explains a lot.

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The vagus nerve is really no different from the long peripheral nerves except it really can’t be tested like other nerves can. The B12D will damage it just like any other nerve. But it is a shorter nerve and may not have as large an impact to attenuation of signals. It controls the hunger sensation to the brain and causes the parietal cells to produce acid in response to food smells and stress.

The intrinsic factor is produced in response to acid in the stomach and other factors we haven’t figured out yet.

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Nothing I can find in the literature suggests that such a thing happens. Damage to the vagus nerve is very unlikely. B12 nerve damage normally affects the central and peripheral nerves. Apart from the optic nerve it hardly ever effects the cranial nerves. If the vagus nerve were damaged sufficiently to stop acid production then you would be suffering from multiple other symptoms.

Of course, there's nothing to stop you also having PA as well as being vegan.

How do you know you have low stomach acid? The symptoms you describe can have many different causes, all more likely. Low stomach acid is notoriously difficult to diagnose.


Have you tried taking a little organic apple cider vinegar or lemon juice in water prior to eating. This gives stomach acid a wee boost, so our food is broken down & absorned better. The ACV I use is the type with a probiotic culture, so good for gut bacteria too, A small glass of wine or cider with meals might have the same effect. ACV makes a tasty condiment if you like it, or balsamic vinegar.

Sorry I can't help with the chicken & egg concept, this is also an issue for hypothyroid folks.


I never had my acid tested but I know for sure that when I was B12 deficient I had real difficulty digesting anything, especially in the morning. Only after I got loaded up by around 16 B12 injections over 2 months I was able to digest better.

I did try the soda bicarbonate home stomach acid test in the morning and it did take me a long time to burp which could indicate I still have low stomach acid but I don't know how conclusive that test is.



I have to agree with fbirder.

Damage to the nerve in the way described is virtually impossible.

The only way to tell for sure if you have a low stomach acid, low probiotics, high bacterial infection/ candida or parasites is to do a comprehensive stool analysis. I’d estimate it costs £200 ish.

I have seen many and they are v helpful. If you go through thyroid uk or can get a doctor/ specialist to sign off on one the Geneva report is the most comprehensive I’ve seen.

You are given a score from 0-4 on the items I mentioned above. The parasites can be added on to the test.

It’s fairly easy to rectify low stomach acid ( say 0 comes back.) with betain hcl. You don’t need to be on the capsules for ever, your body will let you know when it’s increased.

Low probiotics are easy- take some but vary them as say Swanson do different varieties.

Overgrowth of bacteria will come back as a 3/4. Uva ursi helps this.( the report is v specific on which Baxter it is)

Candida is more difficult to eradicate. Cutting own sugar and fruit and adding in pau d’arco is an option. If it’s v severe then you’d need meds like flucozanole. ( usually that’s hand in hand with toe nail infections).

Also the report tells you which antibiotics are best suited to you. Tons of helpful information.

PA and low stomach acid don’t necessarily go hand in hand.

So sorry but I have to agree being vegan is an up hill climb when you want to get better. ( but that’s your choice and I fully respect it.)

If I can help further please do ask.

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Hi, I agree Pvanderaa seems v well informed. I use organic unfiltered cider vinegar (contains the fermenting mother) available at most supermarkets, Grape Tree etc. I use with every meal, I buy organic dried mint (waitrose) and grow my own. Fresh mint or dried I mix with the vinegar - my healthy mint sauce and have with every meal, or cider vinegar with butter on jacket potaoes then just tastes like chips :) or lemon juice on salads. If I cook with lemon eg on baked salmon I eat the lemon as well. I havent taken as I don't have signs of poor digestion, but most people say if you do then take digestive enzymes to help support. Fresh pineapple also contains lots of enzymes helpful if eat with your meal. And Papaya too (not good tho if not organic as heavily sprayed, and we don't seem to be able to get organic papaya in the UK. So the best alternative is order 'Rochway's' organic papaya tea

Just put a spoonful and pour on boiling water, Let it cool enough to drink as everyday tea, or pour in half a mug of boiling water and let it stand to get more of the components into the water and after as long as you want, pour on more boiling and drink as hot tea. It tastes no worse than green tea.

Fbirder states that it is difficult to diagnose low stomach acid and it no doubt it will be with testing but all Functional medical doctors/clinicians agree that poor digestion is caused by low stomach acid and heartburn is not the result of too much stomach acid but too little. This has been clearly proven but our chemists touting indegestion meds and doctors still tout the high stomach acid theory.

Certainly Gluten issues - if coeliac condition (autoimmune - villi in the digestive tract being attacked by the immune system and damaged to the extent where nutrients cannot be absorbed into the blood stream) This damage would happen over many years and people who always had eaten wheat there whole lives/ other grains can find suddenly they have an issue of illness of some form. My mum at the age of 50 was admitted to hospital dying of malnutrition - eventually they diagnosed coeliac disease. She had, had several tests for coeliac previously and always negative. Testing is not reliable and gives 70% false negatives. In addition there are 60 gluten proteins that can trigger the immune system and the NHS test for 2. Professor David Sanders Gastroenterologist Sheffield Hallamshire Hospital has had many papers published and has also written a book (possibly 2017 or thereabouts) Google Dr Tom O'Bryan's you tube videos/ books. Some on his website (thedr.com)

Also, you need to take the health of your microbiome seriously (your intestinal gut micro organisms, populations being devasted by antibiotics and any meds) You are eating food to feed your microorganisms and so what you feed them depends on what colonies you are encouraging and supporting, for good health or poor. These organisms release vitamins and nutrients from your food or make them, message all function including your brain and mitochondria in cells. There's a series actually broadcasting interviews of the top cutting edge scientists in this field at this moment - for this week, called the 'Interconnected Serious'

Hope this helps

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"all Functional medical doctors/clinicians agree that poor digestion is caused by low stomach acid and heartburn is not the result of too much stomach acid but too little. This has been clearly proven"

Ah, proven eh! That means there is evidence. Please point us towards it.

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Hi fbirder, not sure why your apparent aggression "Ah, proven eh!" surely we are all on here to try and help one another. What's the current research state? Is there any evidence that such Functional medical clinicians quote? Do you know of any studies :) ? would have been far more polite and conducive to informed discussion.


Hi lownskater, Here is quite a comprehensive article (referenced) re low stomach acid complications. Jonathan V Wright MD mentioned in the article as long ago as 2001 wrote a book specifically about the confusion

'Why Stomach Acid Is Good For You'

Chris Kresser (Kresser Institute) has also researched this health issue as well as coroberating results in his clinical practice and created a free online e book re GERD (studies referenced using highlighted numbers to take you to the research studies)

British Dr Natasha Campbell McBride MD, MMed (Sci Neurology) MMed (Sci Nutrition) Author - Research author SIBO and clinical effects 'Gut and Psychology Syndrome'

Functional MD's (whose approach is to get to the root of the problem concurr


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