Biochemistry, physiology of vitamin B 12 and pathology or clinical aspects of its deficiency was taught in MBBS in such a way that by the time I passed MBBS my mind was full of notions/ideas of this topic destined to be turned up side down and proved to be myths by the accumulation of added knowledge, experience and wisdom. No one is to be blamed for this because that was a time when facilities to test for vitamin B 12 and folate were hardly available in government colleges and hence no one ( including doctor teachers of medical colleges ) had an in-depth understanding of normal values of vitamin B 12 deficiency and the variety of clinical manifestations resulting from its deficiency.
The only time when vitamin B 12 came up for discussion was the rare chronic malnourished alcoholic with full blown megaloblastic anaemia in whom low vitamin B 12 was documented. One of the first myths that…
