Our study shows that it is reasonable to assume harm will eventually occur in some patients with metformin-induced low vitamin B12 levels,” the researchers wrote.

The researchers found that Metformin Dosage seems to inhibit the intestine’s absorption of vitamin B12. Fortunately, calcium supplements appear to reverse this effect.

Vitamin B12 is critical for maintaining nerve and red blood cell health. It can be found in animal products, nutritional yeast and fortified breakfast cereals. Symptoms of deficiency include anemia, fatigue, nerve damage and cognitive changes. Because similar symptoms often occur in diabetics and the elderly, deficiency may be hard to detect in such populations. Yet while B12 deficiency can carry severe consequences, it is relatively easy to correct with supplementation.