Low intrinsic factor in gut that hampers absorption of B12, pernicious anemia, parasites
in the gut, diet poor
in Vit B12, Crohn;s disease, IBS, or poor metabolism by liver are the causes behind it. Please consult a doctor to rule these out. Take a diet rich in Vit B12 which should include meat and animal products, cheese, such as beef, liver, salmon, cod, and eggs. Take B12 supplements and breakfast cereals fortified with vitamin B12. Finding the cause is important.