Quest Vitamins LTD,
Issue #61 : A-Z of Nutrition: Vitamin B12 (cobalamin)Vitamin B12 contains cobalt and it is hence known as cobalamin. It is another member of the water-soluble B complex, and is sometimes known as "anti-pernicious" factor after its ability to prevent the condition pernicious anaemia. The absorption of vitamin B12 is dependent on the presence of a certain substance known as "intrinsic factor" in the gastric juices. Vitamin B12 is freely soluble and therefore lost into cooking water. It is sensitive to strong acid, alkali and light.
What does it do?
B12 is needed for synthesis of DNA, metabolism of fatty acids, and maintenance of the myelin sheath around the nerves. It has been investigated for use by MS sufferers.
What are the deficiency signs?
Unfortunately there is an unpleasant twist to vitamin B12 deficiency, in that symptoms of pernicious anaemia can be effectively masked if folic acid intake is inadequate. This can allow vitamin B12 deficiency to progress silently, showing itself eventually in irreversible neurological damage.
Who should supplement?
This is a suitable precaution because of the absence of this vitamin from plant foods (1).
High levels of vitamin B12 have also been used therapeutically for reasons other than treating pernicious anaemia. Certain mental conditions (especially in the aged) have been seen to be improved with vitamin B12, but there is no hard evidence for this.
Is it toxic?
Intake levels: micrograms (µg)