ArticlePloS one2022
Influence of metformin intake on serum vitamin B12 levels in patients with type 2 diabetes mellitus.
Article in PloS one, 2022. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 5 papers.
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Who cites it
5 citing papers in PubMed.
- What ultimately underlies vitamin B12 and folate deficiency in subjects treated with biguanides?Hormones (Athens, Greece) · 2026Review
- Rapid Restoration of Circulating Vitamin B12 Levels by Using Oral SucrosomialPharmaceutics · 2026Article
- Impact of Metformin Therapy on Vitamin B12 Levels in Patients With Type 2 Diabetes Mellitus.Endocrinology, diabetes & metabolism · 2025Article
- Morel-Lavallée Lesion in a Patient With Metformin-Induced B12 Deficiency: A Rare Complication Following a Fall.Cureus · 2025Article
- Review
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2 authors.
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No grant is acknowledged in the PubMed record.
Abstract
objectiveTo describe the prevalence of vitamin B12 deficiency among Jordanian patients with type 2 diabetes mellitus treated with metformin and to compare the findings with those who did not receive metformin. DESIGN AND
methodTotal 155 patients with type 2 diabetes mellitus, aged between 48 and 82 years were enrolled in the current study. They were divided into two groups; the first (n = 120) was treated with metformin while the second (n = 35) was not. Patients' demographics (age, gender, duration of type 2 diabetes mellitus, smoking status), medication parameters (daily dosage and duration of metformin therapy), and biochemical parameters (hemoglobin level, mean corpuscular volume (MCV), serum vitamin B12, and folate level) were recorded. Definite deficiency was defined as serum vitamin B12 levels of < 150 pg/ml, whereas < 200 pg/ml indicated possible deficiency.
resultsThe mean serum ± standard deviation (SD) vitamin B12 level was significantly lower in patients who were treated with metformin (268.5 ± 35.8 vs. 389.5 ± 29.8 pg/ml, p = 0.029). The metformin group had significantly higher prevalence of definite deficiency (32% vs. 9%, p < 0.02) and possible deficiency (48% vs. 30%, p < 0.02). Within the metformin group, the mean serum ± SD vitamin B12 level was significantly lower in those on high dosage (175.2 ± 30.5 vs. 315.6 ± 37.8 pg/ml, p < 0.001). MCV (μm3) levels ± SD were higher in the metformin group (87.5 ± 2.9 vs. 83.7 ± 2.4) with no statistical significance.
conclusionThere is a significant association between metformin intake and vitamin B12 deficiency. Serum vitamin B12 levels should be checked by physicians and serial monitoring is necessary in patients who are treated with metformin.
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