Active B12 5000 contains vitamin B12 as only adenosylcobalamin and methylcobalamin. The product Hydroxo B12 contains vitamin B12 as hydroxocobalamin. None of our products contain the fourth supplemental form, cyanocobalamin.
Hydroxo-B12 is unique in that its structure lends itself to supporting the body's normal detoxification pathways. The other forms (methyl- and adenosyl-) are the primary active forms of B12 within the human body - they are both considered "coenzyme" forms, in that they are active within B12 dependent enzymes. Hydroxo-B12 is not. It easily converts into methyl-B12 within the body. It is preferred over the common supplemental form of B12, cyanocobalamin, because hydroxocobalamin (unlike cyanocobalamin) does not need to lose a cyanide molecule before conversion to one of the active forms.
Methyl-B12 and adeno-B12 (dibencozide) have slightly different functions within the body, with adeno-B12 primarily in cellular tissues and methyl-B12 primarily in blood plasma. Taken as supplements, the efficacy of methyl-B12 is surpassed by that of adeno-B12 in some situations and vice versa. Adeno-B12 may also be easier for individuals who are sensitive to methylated B vitamins to use than the methyl-B12 form.
Your healthcare professional should be able to administer some tests to help you determine which form is best for your individual needs. In healthy individuals, the body is able to convert between forms. For some individuals, however, it may be harder for the body to convert from certain forms to others. The efficiency of these processes varies from person to person.*