Hi All
I became b12 deficient due to a vegetarian almost vegan diet coupled with my gp prescribing Omaprezole to restrict my stomach acid - I had recurring 6 monthly amounts of 10mg a day for over 6 years!
My mother and sister, both of whom were on very restricted diets due to oesophageal problems were both on the same PPI’s but at 20mg - my mother developed dementia and my sister who had diabetes 1died of a heart attack - both on the symptoms list of b12d.
I do not regret being vegetarian/vegan but it does concern me that so many people are advocating vegetarian vegan and flexitarian diets without any warning of b12 deficiency. The latest one I’ve read about is the concept of ‘clean eating’ and trying to get to ones ‘leanest weight’ (what ever that means!). Coupled with the almost daily advocation of flexitarian diets with meat being consumed only several days a week. I support and agree with the latter two and certainly eat as ‘cleanly’ as possible but these changes to diet are being advocated as very healthy and, without b12 supplementation they are most definitely not healthy- even the vegetarian and vegan societies warn that b12 needs to be added to such diets..
As a former teacher, I was aware of many teenagers, mostly female, who for animal welfare reasons in some cases but others for weight loss reasons went on very restricted diets. Many of these women became ill!
The problem with b12 deficiency is the multitude of symptoms it creates which, when shared with doctors who, in my experience, are totally ignorant of b12d and it’s consequences, ends up with patients being taken down medical routes which are completely wrong. As a consequence, they do not receive treatment for b12d!
One doctor wanted to go down the mental illness route with me because I suffered auditory hallucinations- a verifiable symptom of b12 deficiency!
I was lucky at my gp practice as they immediately assumed that I had PA hence the injection regime started and I have never enlightened them about that fact that I can (I think) absorb b12 naturally. This is not true for many people.
I read all the articles about the rise in dementia but never once have I read that b12d may be a major cause. I have elderly friends who are forgetful, have nominal aphasia, balance issues, the shakes etc and I tell them about b12d and they just shrug their shoulders and ignore me as their doctors in almost all cases are treating their symptoms with drugs - with a lot of them prescribed ppi’s.
I think b12d is dangerously under reported and that many illnesses that young women and elderly people suffer from should be looked at from the position of b12 deficiency as given the dietary life style changes which are being advocated and the decline in the ability to absorb b12 that comes naturally with ageing we, as a society, are heading for an awful lot of very ill people.
I hope my comments add to the debates on this site and that they are helpful.
Good health
Various B12D/PA resources 
Difference between PA and B12 deficiency
B12d and Cortisol?
