In October 2013 the Pan African Medical Raika Diabetes Reverser Review Journal reported the results of a study on metformin and vitamin B12 deficiency. Metformin is a first-line drug for treatment of Type 2 diabetes. The study, carried out in the Combined Military Hospital in Kharian, Pakistan, included...
Thirty-five Type 2 diabetics, or 31 percent, were found to have low vitamin B12 levels, compared to only 9, or 8.6 percent, among nondiabetics. Those taking the highest doses of metformin had the lowest levels of B12.
From this information it was suggested Type 2 diabetics taking metformin should be screened for vitamin B12 deficiency.
Blood vitamin B12 levels can be measured with a blood test. Normal values range from 200 to 900 pg/mL (picograms per milliliter). Another blood test called a complete blood count, or CBC, can tell if megaloblastic anemia is present.