Metformin and Vitamin B12 Deficiency: Where Do We Stand?

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.

Haematological Parameters and Vitamin B12 Levels in Type Ii Diabetic Patients on Metformin- A Prospective Case Control Study

“…DOI: 10.18410/jebmh/2018/478 BACKGROUND Type 2 diabetes mellitus (T2DM) is a chronic metabolic disorder that is increasingly becoming a pandemic in developed and developing worlds. 1 According to the World Health Organization, the number of type-2 DM patients is expected to double within the next 25 years 2 and according to International Diabetes Federation there were over 72 million cases of diabetes in India in 2017.…”

Low hydration status may be associated with insulin resistance and fat distribution: analysis of the Korea National Health and Nutrition Examination Survey (KNHANES) 2008–2010

“…However, our results should be interpreted in the context of risk-benefit considerations. Several of the previous approaches to improve insulin sensitivity involved the use of various medications (10,19,31) , which are not free from inadvertent side effects (9,32,33) . Although lifestyle modification with exercise is a must for people with diabetes, it is very difficult to achieve and maintain (34) .…”

Vitamin B12 deficiency: metabolic effects, clinical evaluation, and treatment

“…In the methylmalonyl-CoA mutase pathway, the enzyme methylmalonyl-CoA hydrolase (MCH) catalyzes the hydrolysis reaction of methylmalonyl-CoA accumulated in MMA. 14 MMA is a more specific marker for cobalamin deficiency, since it increases in the blood due to lack of this vitamin, but not in that of other B-complex vitamins. 3,17 signs of acute leukemia.…”

“…[41][42][43] And high plasma (HC) concentrations may result in falsely elevated serum levels of vitamin B12. 14…”

“…5 The laboratory cutoff points used for holo-TC vary between 11 and 41 pmol/L 47 and their levels can be altered by the use of contraceptives, renal or hepatic disease, 48,49 folate disorders, myelo-dysplasia, certain hematological disorders and alcoholism, 47,50,51 Some more limitations to the use of holo-TC as an isolated marker to assess vitamin B12 status are the lack of clarification about its synthesis sites and its pharmacokinetics and limited use in research and clinical practice. 14…”