One of the most common arguments used against the vegan diet is the argument that you will develop a nutritional deficiency and, in particular, a deficiency in vitamin B12.
However, although it is possible for a vegan to have a vitamin B12 deficiency, being a vegan doesn’t necessarily mean you will become vitamin B12 deficient.
Vitamin B12 deficiency can easily be found in fortified food or drinks such as Vitasoy Original Soy Milk, which contains 50% of your recommended dietary intake of vitamin B12 per cup. Vitamin B12 can even be found in Braggs Nutritional Yeast as well a vegan meat from the Fry Family Food Co. In Australia, the Vitasoy soy milk and Fry Family vegan meats can be found in Woolworths (also known as Safeway) supermarkets. Nutritional yeast is more difficult to find, in my opinion.
If your diet is low in vitamin B12 fortified food, an alternative is to take vitamin B12 supplements, which can be purchased from either your local chemist or online via major retailers such as Amazon or iHerb.
However, some people have raised concerns that most vitamin B12 supplements on the market contain cyanide in them and therefore they are poisonous.
There are B12 supplements without cyanide called methylcobalamin. Many vegans who are afraid of cyanide poisoning take this form of vitamin B12 due to fears of cyanide poisoning. However I take cyanocobalamin. I am aware it contains cyanide in it (or when it breaks down in the body it forms cyanide), but I do not consider it harmful. The levels of cyanide are too small to be of any harm.
Cyanide is a natural chemical that is found in water, soil, and even the air that you breathe as well as fruits and vegetables that you eat. The amounts found in cyanocobalamin are so small that they pale in comparison to the amount you absorb naturally via vegetables, air, etc. Jack Norris RD’s page provides a great explanation:
“The safety of cyanocobalamin has raised concerns due to the fact that cyanide is a component of cyanocobalamin, and the cyanide molecule is removed from cyanocobalamin when used by the body’s cells. Cyanide is also found in many fruits and vegetables and so humans are always ingesting small amounts of cyanide, and like in most fruits and vegetables, the amount of cyanide in cyanocobalamin is considered to be physiologically insignificant.
“According to the European Food Safety Authority, ‘Data of from a Norwegian dietary survey show that the average and high (97.5th percentile) daily intake of [cyanide] among consumers amounts to respectively 95 and 372 micrograms/person or 1.4 and 5.4 micrograms/kg bw/day (7).’ The amount of cyanide in a 1,000 microgram cyanocobalamin is 20 micrograms.”