Vitamin B12 deficiency among vegetarian and non-vegetarian diabetic population receiving prolonged Metformin based oral hypoglycemic agents therapy

Vivek Kumar Verma, Ranjit Kumar Nim, P. S. Singh, Manoj Kumar, Geeta Singh, Anand Kumar Singh


Background: Diabetes is a group of metabolic disorder that share the phenotype of hyperglycemia. Over the period of time the metabolic dysregulation associated with diabetes mellitus causes secondary pathophysiological changes in multiple organs like heart, blood vessels, eyes, kidney and nerves resulting in various complications. However, a common potential interaction of metformin with vitamin B-12 is well documented but is poorly studied by the physicians who prescribe metformin to their diabetic patients. Since vitamin B-12 deficiency is common among vegan population as compared to population consuming food of animal origin (meat, fish and dairy products). But in this article, it has been studied that metformin cause vitamin B-12 deficiency even in non-vegetarian population. The aim of this study was to asses’ vitamin B12 deficiency among vegetarian and non-vegetarian diabetic population receiving prolonged Metformin based oral hypoglycaemic agents therapy. It was a cross sectional study done in Department of Medicine, UPUMS, Saifai, Etawah, Uttar Pradesh, India.

Methods: Study done among patients of type 2 diabetes mellitus of age group 30-60 years on prolonged metformin based OHA therapy and having peripheral neuropathy were included in study. Data was analysed on SPSS Version 22.0 and p value obtained.

Results: Statistical analysis of 93 patients included in study showed that vitamin B12 deficiency is common among the vegetarian (56.52%) and non-vegetarian (35.71%) population but the difference is not statistically significant (p value=0.29) which is more in favour of metformin associated vitamin B12 deficiency in non-vegetarian population.

Conclusions: Vitamin B12 deficiency is common in diabetes patients on metformin based OHA therapy hence we recommend routine screening for Vitamin B12 deficiency in such diabetes patients.



Diabetes Mellitus, Metformin, Vitamin B12, Peripheral Neuropathy, Non-vegetarian, Vegetarian

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Charles H Best. Available at The website. Retrieved. 2015;11:26.

Melmed S, Polonsky KS, Larsen PR, Kronenberg HM. Williams Textbook of Endocrinology, 12th edition. Philadelphia:Elsevier/Saunders; 2012:1371- 435.

Wild S, Roglic G, Green A, Sicree R, King H. Global prevalence of diabetes: estimates for the year 2000 and projections for 2030. Diabetes Care. 2004;27(5):1047-53.

International Diabetes Federation. IDF Diabetes Atlas, 6th edition. Brussels:IDF; 2014.

WHO study group. WHO Technical Report Series,727. Geneva:WHO;1994.

Classification and diagnosis of diabetes: Diabetes Care. 2015;38(Supplement 1): S8-S16.

American Diabetes Association. Diagnosis and classification of diabetes mellitus. Diabetes Care. 2004;27(Supplement 1);5-10.

World Health Organization. WHO global status report on noncommunicable disease, 2010. Geneva:WHO;2011.

Duby JJ, Campbell RK, Setter SM, White JR, Kristin A. Rasmussen. Am J Health Syst Pharm. 2004;61(2).

Vinik AI, Park TS, Stansberry KB, Pittenger GL. Diabetic neuropathies. Diabetologia. 2000;43:957-73.

Nathan DM, Buse JB, Davidson MB, Heine RJ, Holman RR, Sherwin R, et al. Management of hyperglycemia in type 2 diabetes: a consensus algorithm for the initiation and adjustment of therapy. Diabetes care. 2006;29(8):1963-72.

Nathen DM,Base JB,Davidson MB,et al Management of hyperglycemia in type-2 diabetes: a consensus alogorithm for the initiation and adjustment of therapy: update regarding thiazolidinediones: a consensus statement from ADA and EA for study of Diabetes. Diabetes Care. 2009;32:193-203.

UKPDS 34, UK Prospective Diabetes Study Group. Lancet. 1998;352:854-65.

Bailey CJ, Wilcoc CK, Scarpello JH. Metformin and intensive therapy. Diabetolgia. 2008;1552-3.

Pflipsen M, Oh R, Saguil A, Seehusen D, Topolski R: The Prevalence of vitamin B12 deficiency in patients with Type 2 Diabetes: a cross-sectional study. J Am Board Fam Med. 2009;22:528.

Hermann L, Nilsson B, Wettre S: Vitamin B12 status of patients treated with metformin: a cross-sectional cohort study. Br J Diab Vascular Dis. 2004;4:401.

Nervo M, Lubini A, Raimundo F. Vitamin B12 in metformin-treated diabetic patients: a cross-sectional study in Brazil. Rev Assoc Med Bras. 2011;57:46-9.

Liu K, Dai L, Jean W. Metformin-related vitamin B12 deficiency. Age Ageing. 2006;35:200-1.

Bell D. Metformin-induced vitamin B12 deficiency presenting as a peripheral neuropathy. South Med J. 2010;103:265-7.

Kumthekar A, Gidwani H, Kumthekar A. Metformin associated B12 deficiency. J Asso Phy Ind. 2012;60:58-9.

Kos E, Liszek M, Emanuele M, Durazo-Arvizu R, Camacho P: effect of metformin therapy on vitamin D and vitamin B12 levels in patients with type 2 diabetes mellitus. Endocr Pract. 2012;18:179-84.

De-Jager J, Kooy A, Lehert P: long term treatment with metformin in patients with type 2 diabetes and risk of vitamin B-12 deficiency: randomised placebo controlled trial. BMJ. 2010;340:c2181.

Ting RZ, Szeto CC, Chan MH, Ma KK, Chow KM. Risk factors of vitamin B12 deficiency in patients receiving metformin. Archives Int Med. 2006;166(18):1975-9.

Reinstatler L, Qi YP, Williamson RS, Garn JV, Oakley GP. Association of biochemical B12 deficiency with metformin therapy and vitamin B12 supplements. Diabetes care. 2012;35(2):327-33.

Qureshi S, Ainsworth A, Winocour P. Metformin therapy and assessment for vitamin B12 deficiency: is it necessary?. Practical Diabetes. 2011;28:302-4.

Marar O, Senturk S, Agha A, Thompson C, Smith D. The prevalence of vitamin B12 deficiency in patients with type 2 diabetes mellitus on metformin. Royal College of Surgeons in Ireland Student Medical Journal. 2011;4(1):16-20.

Ting RZ, Szeto CC, Chan MH, Ma KK, Chow KM. Risk factors of vitamin B12 deficiency in patients receiving metformin. Arch Internal Med. 2006;166:1975-9.