Vitamin B12 is a water soluble vitamin. Vitamin B12 is typically consumed in sufficient amounts in omnivorous diets. However, poor absorption due to a variety of factors combined with the increase in plant based diets has led to vitamin B12 insufficiency in large segments of the global population.
Types of vitamin B12
There are 4 main types of vitamin B1
Methylcobalamin and 5-deoxyadenosylcobalamin are the metabolically active forms of vitamin B12.
However, the two others forms, hydroxycobalamin and cyanocobalamin, become biologically active after they are converted to methylcobalamin or 5-deoxyadenosylcobalamin
Cyanocobalamin is the most used form due to its high stability, cost effectiveness and safety of use
Cyanocobalamin is a more stable and inexpensive form that appears to be best suited for oral supplementation
Obeid, R.; Fedosov, S.N.; Nexo, E. Cobalamin coenzyme forms are not likely to be superior to cyano- and hydroxyl-cobalamin in prevention or treatment of cobalamin deficiency. Mol. Nutr. Food Res. 2015, 59, 1364–1372.
'Methylcobalamin is less stable than cyanocobalamin, and it is particularly susceptible to photodecomposition' (photodecomposition means the vitamin B!2 acrtivity being decreased when exposed to light such as sunlight)
- Mariotti F, ed. Vegetarian and Plant-Based Diets in Health and Disease Prevention. Academic Press; Cambridge, MA, USA: 2017.
'There is no advantage to using the light-sensitive forms of cobalamin, such as methylcobalamin or 5-deoxyadenosylcobalamin, instead of the stable cyanocobalamin or hydroxycobalamin forms, which are readily converted in the body into the coenzyme forms, methylB12 and adenosylB12'