Abstract:
The association between metformin use and low vitamin B12 levels in type 2 diabetes mellitus
patients is well-established. However, many aspects of the topic remain to be elucidated. There is still
controversy on the current diagnostic approaches to vitamin B12 deficiency. It is now believed that measuring
the serum levels of the vitamin may not reflect its metabolic status. Moreover, there were conflicting results
from studies attempting to quantify and explore metformin-associated vitamin B12 deficiency and its clinical
impacts. This article reviews the cellular functions of vitamin B12, the biomarkers utilized to define the vitamin
deficiency and metformin-induced vitamin B12 deficiency with an emphasis on its prevalence and clinical
impacts.
