Saima Zahid, Kiran Qadeer, Iqbal Ahmad.
Physicochemical Characteristics, Biological Functions and Deficiency of Cobalamins.
Baqai J Health Sci Jan ;14(2):59-64.

Cobalamins are complex organometallic compounds of biological interest present in animal food products including meant, eggs and milk. The clinically important cobalamins, i.e. cyanocobalamin (vitamin B12), hydroxocobalamin and methycobalamin exist as coenzymes in biological system and are involved in several biochemical functions. The deficiency of vitamin B12 occur mainly due to its malabsorption and results in pernicious anemia. This disease is age related and is associated with the destruction of parietal cells in the stomach. Clinical studies with high dose supplementation of cobalamins suggest a strong correlation between the duration of congnitive symptoms of the disease and the therapy. Neural tube defects and other birth defects have also been reported with cobalamin deficiency.

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