May 25, 2010
By Kate Kelland
Dutch scientists who carried out the study said the findings suggest that regular checking of vitamin B-12 levels during long-term metformin treatment should be “strongly considered” to try to prevent deficiency and its effects.
Vitamin B12 is essential to maintain healthy nerve cells and red blood cells. It is found in meat, dairy products, eggs, fish, shellfish and fortified breakfast cereals, and it also can be taken as a supplement.
Coen Stehouwer of Maastricht University Medical Center in the Netherlands, whose study was published in the British Medical Journal, said symptoms of B12 deficiency include fatigue, mental changes, anemia and nerve damage known as neuropathy.
All these symptoms can easily be misdiagnosed as being due to diabetes and its complications, or to aging, he said, but checking B12 levels could help doctors to assess the real cause and treat it if it was found to be B12 deficiency.
“Our data provide a strong case for routine assessment of vitamin B12 levels during long term treatment with metformin,” Stehouwer wrote.