Why is vitamin B12 so dangerous?

[ltr]Image source: Pathophysiology and laboratory diagnosis of pernicious anemia[/ltr]

[list=q-box][*]Vitamin B12 is the most well tolerated vitamin of them all. There is literally no toxicity at any concentration. How Much Vitamin B12 Is Too Much?

[*]The problem is when there is a lack of it leading to pernicious anemia. Pernicious Anemia. The parietal cells produce the intrinsic factor, which is needed for vitamin B12 to be absorbed into the blood.

[*]Many older people have a chronic atrophic gastritis, which leads to a loss of intrinsic factor production. These people become vitamin B12 deficient and develop pernicious anemia. However, every physician knows that these people can be treated successfully with Vitamin B12 injections on an ongoing basis: How Often Can I Take B12 Injections? - Soza Clinic.

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