Active Low-Carber Forums - View Single Post - Metformin and B12 deficiency

Just read this this morning:
Annual Vitamin B12 Supplementation may become Mandatory with Long-Term Metformin Use

Apparently Metformin causes your B12 stores to go low. I don't know if doctors test it routinely or not -- probably not knowing how horrible doctors are about such things. But I'd take a B12 supplement if you're on Metformin (sublingual methylcobalamin is best) because B12 deficiency is vicious and irreversible.

Quote:

Chronic metformin use results in vitamin B12 deficiency in 30% of patients. Exhaustion of vitamin B12 stores usually occurs after twelve to fifteen years of absolute vitamin B12 deficiency. Metformin has been available in the United States for approximately fifteen years. Vitamin B12 deficiency, which may present without anemia and as a peripheral neuropathy, is often misdiagnosed as diabetic neuropathy, although the clinical findings are usually different. Failure to diagnose the cause of the neuropathy will result in progression of central and/or peripheral neuronal damage which can be arrested but not reversed with vitamin B12 replacement. To my knowledge, this is the first report of metformin-induced vitamin B12 deficiency causing neuropathy.