Autoimmune Metaplastic Atrophic Gastritis (AMAG) results in the loss of parietal cells which causes a loss of production of stomach acid and intrinsic factor (IF). The loss of IF results in low B12.
My general query is; are there consequences and symptoms connected to a lack of stomach acid/intrinsic factor other than the inability to absorb vitamin b12?
Such as loose stools, bloating and ibs.
Also, is the ability to absorb iron, vitamin D and folic acid affected? I have a good diet, but my levels are always low unless I supplement. Is this the reason?
TIA
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Laundretta
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Yes , the loss of parietal cells leads to Hypochlorhydria(low stomach acid ) or Achlorhydria( no stomach acid) Food does not get broken down effectively, so leads to malabsorption of vitamins , minerals and trace elements Also having low stomach acid can mean that harmful bacteria in the stomach cause bloating and pain .
Good to take an acidic drink with meals containing protein . Some people with severely low stomach acid , take Betaine Hydrochloric. acid with pepsin .to help .
Wise to eat smaller meals , but more often , and to chew food thoroughly . This is a good start towards breaking food down .
I found that I had started on B12 injections , the bloating and stomach pain ceased .!I don’t even need the acidic drinks anymore,
It's actually Autoimmune Metaplastic Atrophic Gastritis (AMAG) that results in loss of parietal cells and intrinsic factor IF The loss of IF results in low B12. So it's the reverse of how you stated.
Parietal cells also produce gastric acid. So yes the loss of those will cause low/no gastric acid. With that there is a whole host of digestive issues from, SIBO, IBS, leaky gut, bouts of diarrhea, constipation, malabsorption if nutrients one being iron. Also, acid plays a role in regulating both the esophageal sphincter and pyloric sphincter. In advance stages with achlorhydria there may be times when shortly after eating there is a feeling of intense fullness, nausea, and eventually vomiting as the food just will not process. Acid reflux may also be experienced.
There is also an increased, 3 to 7 fold increase in the risk of gastric cancer for those with AMAG. This is due to the Metaplastic nature of this condition where your body replaced destroyed parietal cells with cells call intestinal metaplasia. So called because they resemble cells that belong in the small intestine. These cells are considered precancerous however most will never progress to cancer. So just be aware and if you've been diagnosed with PA you should have a gastric mapping upper GI endoscopy if in US, or called Gastroscopy in Europe
Thanks for the clarification. I did understand it that way around, but I did write it very badly- I’ve edited my post to avoid confusion.
Sadly, although I’m pretty sure I have PA as my body displays all of the above symptoms and will not retain vitamin b12, I don’t have a gp diagnosis. In 2018 my total b12 bloods were low normal and gp refused to treat until it went below range. (Active b12 was already below range, but gpnot interested in that) I felt awful so started to si.
Gp has stated I need to stop si and let my b12 drop to nhs levels of low for them to diagnose/treat me, despite me being able to show that my b12 dropped from over range to low normal over 2 years while si bi-monthly. (I now si monthly)
Well there is some logic your GP is using that makes sense. Please don't tell anyone I said that! 😊
The tests for PA are Homocysteine, MMA, IFaB, PCaB, Gastrin. All are blood tests and supplementing with B12 or biotin can interfere with the test results. Also each by themselves are not entirely conclusive if PA. The only 100% diagnostic today is gastric biopsies. That's expensive so they will need some positive tests prior to that.
You're are correct in the IFaB negative. 50% of those with PA will "show" negative. Not because they don't have the IFaB but rather the IFaB test sensitivity is purposefully tuned or dialed to be less sensitive to IFaB to eliminate false positives. So really 100% if those with PA have this antibody but only 50% show it.
My hypotheses is that as the disease progresses you get more and more antibodies until one day you have enough they will show their pretty faces to th test.
In 2020 I had positive PCaB but negative IFaB. Then my diagnosis of PA was confirmed by endoscopic biopsies. So to test my hypothesis, only a sample one (me) I asked for the PCaB and IFaB test for each blood test which was about every three to four months. Before each test I stopped supplementing everything for one month. My PCaB was consistently positive my IFaB was consistently negative until May 2023 when it showed too showed positive.
Unfortunately there are no good standard test PA. The dilemma is that it's both so important to treat with B12 but that interfere with the tests yet its also critically important to get a correct firm diagnosis because as I say with PA "It ain't just B12!" 😳. Hence your questions as you're now having digestive issues unrelated to B12 but rather low/no gastric acid also caused by this disease.
I agree that it isn't just B12, but if Dr Chandy is right, it is the undiagnosed B12D affecting folate cycle functioning that commonly leads to the autoimmunity - PA included. So identifying and treating early may prevent progression to PA. And the low/no acid can be from other autoimmunity (thyroid, vitiligo, coeliac...) or simply the effect of ageing on GPC function. I like your hypothesis and self test. After some time, antibodies may reduce again (as I understand it) as the immune system exhausts itself, so those with years of symptoms but low antibodies can be far more unwell than those with recent symptoms and high levels - that can be the case with thyroid AIs anyway. Cheers
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Help with a mystery needed
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