Vitamin B12

Vitamin B12

Vitamin B12 is cobalamin, and cyanocobalamin is a man-made form thereof. It's biological half-life is ~6 days (400 days in the liver)

The active form of Vitamin B12 is methylcobalamin, or "methyl B12". [Source needed]

Methylcobalamin has the following advantages:

• It is the natural form of cobalamin
• Does not require conversion, within the body, to the methyl form
• Does not produce cyanide within the body

See also

http://www.paulgolding.id.au/B12_AND_FOLATE/Pages/B12AndFolateInformation/B12Notes/Treatment/OralB12Supplements.html

To review following studies;

• Effects of methylcobalamin and cobamide on EMG patterns and loss of muscle weight in rats with crushed sciatic nerve. Folia Pharmacol Japon 1976;72(2):259-68. [Japanese]
• Ultra-high dose methylcobalamin promotes nerve regeneration in experimental acrylamide neuropathy. J Neurol Sci 1994;122(2):140-3.
• Effect of ultrahigh-dose methylcobalamin on compound muscle action potentials in amyotrophic lateral sclerosis: a double-blind controlled study. Muscle Nerve 1998;21(12):1775-8.

Storage

• Methylcobalamin is light sensitive
• Methylcobalamin may be temperature sensitive