Adenosylcobalamin | Cobamamide | Dibencozide | Coenzyme Vitamin B12 | Vitamin B12 | Cobalamin
Vitamin B12, or cobalamin, is unique among vitamins because it contains a metal ion, cobalt, from which the term cobalamin derived. Adenosylcobalamin is one of the two coenzyme forms of vitamin B12 (the other is methylcobalamin). These are the forms used in enzymes in the human body. Adenosylcobalamin is used in only one enzyme, L-methyl-malonyl-CoA mutase. This enzyme sits at a crossroads of sorts between the Krebs cycle and many amino acids. In this role it’s important for cellular energy production and building many important molecules.
Vitamin B12 can be found in different forms, including cyanocobalamin, hydroxycobalamin, adenosylcobalamin, and methylcobalamin. Adenosylcobalamin and methylcobalamin are considered to be the coenzyme forms, because they are what’s used in enzymes in the body.
The adenosylcobalamin form is selected when a biologically active form of vitamin B12 is desired and the formulation’s goal is to support the Krebs cycle and cellular energy production.
Adenosylcobalamin sourcing is focused on ensuring it is non-GMO, gluten-free and vegan.
Adenosylcobalamin is dose-dependent (see Neurohacker Dosing Principles) in the range it’s commonly dosed (up to about 1 mg), with higher doses doing a better job in normalizing functional markers of vitamin B12 status than lower doses. The RDA for vitamin B12 is very low. Vitamin B12 function is not always maintained at these low levels, with functional status sometimes requiring substantially higher doses to normalize.  Relative insufficiencies are more common with older age and in persons eating a vegetarian or vegan diet (vitamin B12 is found in animal products but not plants).
L-methyl-malonyl-CoA Mutase Activity
Cardiovascular and cerebrovascular function
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