What is vitamin B12?
Vitamin B12 is a member of the vitamin B complex. It contains cobalt, and so is also known as cobalamin. It is exclusively synthesised by bacteria and is found primarily in meat, eggs and dairy products. There has been considerable research into proposed plant sources of vitamin B12. Fermented soya products, seaweeds, and algae such as spirulina have all been suggested as containing significant B12. Vitamin B12 is necessary for the synthesis of red blood cells, the maintenance of the nervous system, and growth and development in young birds. Deficiency can cause anaemia. Vitamin B12 neuropathy, involving the degeneration of nerve fibres and irreversible neurological damage, can also occur.
Functions:
Vitamin B12's primary functions are in the formation of red blood cells and the maintenance of a healthy nervous system. Vitamin B12 plays a vital role in the metabolism of fatty acids.
B12 is necessary for the rapid synthesis of DNA during cell division. This is especially important in tissues where cells are dividing rapidly, particularly the bone marrow tissues responsible for red blood cell formation. If B12 deficiency occurs, DNA production is disrupted and this results in anaemia. Symptoms include excessive tiredness and poor resistance to infection. Anaemia may also be due to folic acid deficiency, folic acid also being necessary for DNA synthesis.
Vitamin B12 can be stored in small amounts by the body. Around 80% of this is stored in the liver.