Researchers in Pakistan have found that vitamin B12 deficiency is common amongst type 2 diabetics.  

Vitamin B12 levels were measured in 44 subjects with diabetes (40-70 years) who were not currently using Metformin. 48% of patients had low vitamin B12 levels (<200 microgram/dL). 10 of the subjects were subsequently administered 1500 µg/day of oral mecobalamin for 3 months. The supplement rapidly normalised vitamin B12 levels, which is a clear indication that vitamin B12 deficiency among these patients is not due to mal absorption.  

Diabetes can result in the development of a family of nerve disorders associated with the elevated blood glucose that characterises the condition (diabetic neuropathies). Vitamin B₁₂ deficiency is known to damage the protective myelin sheath covering nerves; symptoms of deficiency include numbness and tingling of the arms and legs.  The findings of this study suggest that vitamin B12 deficiency may be a contributory factor in the development of diabetic neuropathies. The authors concluded that, in addition to glycemic control, vitamin B12 supplementation should be considered as part of the treatment of diabetic neuropathy.

Click here to view the study abstract.