where does b12 occur naturally
Humans and all vertebrates require cobalt, although it is assimilated only in the form of vitamin B12. B12 synthesis is known to occur naturally in the human small intestine (in the ileum), which is the primary site of B12 absorption.As long as gut bacteria have cobalt and certain other nutrients, they produce vitamin B12. Dr Michael Klaper argues that vitamin B12 is present in the mouth as well and intestines.umans and all vertebrates require cobalt, although it is assimilated only in the form of vitamin B12. B12 synthesis is known to occur naturally in the human small intestine (in the ileum), which is the primary site of B12 absorption.