Vitamin Bl2 combines with intrinsic factor to
form Vitamin B12 - IF complex.
Vitamin B12 intrinsic factor complex is
absorbed in the ileum.
In the illeal cells the intrinsic factor is
released and the B12 is transferred to a
plasma transport protein transcobalamin II.
Unlike other water
soluble vitamins, vitamin
B12 is stored in the liver
and other tissues
Whole liver contains
about 2mg of B12, which
is sufficient for 2-3 years.
Vitamin B12 act as coenzyme.
Methyl cobalamin is the coenzyme of methionine synthase .
Deoxy adenosylcobalamin is the coenzyme of methyl malonyl-CoA
Vitamin B12 is effective in lowering concentration of plasma
homocysteine of coronary artery disease patients.
• Decrease in absorption
• IF deficiency
• Gastric atrophy
• Fish tapeworm
• Pernicious anemia
•Numbness and tingling of
the hands and feet
Serum B12 Schilling test