Vitamin B12 is a B complex vitamin containing cobalt, nutritionally known as cobalamin. The single source of vitamin B12 is bacteria that synthesize it in meat, dairy products and eggs. Extensive research investigates whether there are plant sources of vitamin B12, but the possibility of procuring vitamin B12 from plant sources remains dubious. Vitamin B12 is essential for red blood cell production as well as growth and development in children.
Potential Vegetable Sources
There are some proposed vegetable sources of vitamin B12, although they remain controversial. Among these sources are undersea vegetation such as edible seaweed and algae. In addition, fermented soybeans are proposed sources of vitamin B12. However, whereas some studies agree that these foods may contain vitamin B12, they contain amounts of this vitamin is so minute that they are not viable. Other studies conclude that edible undersea vegetation in particular does not contain vitamin B12 at all, but rather B12 analogues, which are elements that have a high chemical similarity to vitamin B12, but do not produce the same healthful benefits. In fact, vitamin B12 analogues may even contribute to vitamin B12 deficiency.
Indirectly Fortified Vegetables
There is evidence of some populations garnering vitamin B12 from vegetables. This is likely due to the ingestion of unwashed vegetables fertilized with human feces. Human feces contains high levels of vitamin B12, as the colon contains bacteria that produce the vitamin. However, this bacteria appears in the rectum, which is too far down the large intestine for absorption. Ergo, the vitamin expels in large quantities with feces, which will fortify vegetables that it fertilizes with vitamin B12, especially when these vegetables are left unwashed.
Directly Fortified Vegetables
Some diets specifically exclude meats, eggs and dairy products, most notably, the vegan diet. To ensure that those with such diets do not result in vitamin B12 deficiencies, specially fortified foods are available as of 2010. These foods include raw, dried and prepared vegetables.