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B12 deficiency

Your body needs vitamin B12 in order to create red blood cells and keep the nervous system healthy. It is also needed to absorb folic acid and it helps to release energy. It is absorbed through your intestines from a variety of foods, but mainly meat, fish and dairy products. It can be stored in the body in small amounts, and around 80% of this is stored in the liver. It may take three or four years for the symptoms of deficiency to develop.

Vitamin B12 cannot be absorbed on its own. It has to combine with another substance called 'intrinsic factor' which is produced by your stomach lining.

Vitamin B12 deficiency usually develops for one of the following reasons:

  • Your stomach cannot produce enough intrinsic factor
  • Your intestine cannot absorb enough vitamin B12
  • You do not eat enough food containing vitamin B12 (this may happen to people following a Vegan diet)