Microbial fermentation yields adenosylcobalamin, which is then converted to cyanocobalamin by addition of potassium cyanide or thiocyanate in the presence of sodium nitrite and heat.
Lack of intrinsic factor is most common in older people and usually associated with an autoimmune disease called.
Besides, milk , riboflavin, calcium, phosphorus, magnesium, and potassium.
Moreover, it usually contains other B vitamins, as well as protein, fiber, and antioxidants.
The diets of vegetarians and vegans may not provide sufficient B 12 unless a dietary supplement is consumed.
Vitamin B 12 is the most chemically complex of all vitamins, and for humans, the only vitamin that must be sourced from animal-derived foods or supplements.