A review of studies published recently in the Journal of Agricultural and Food Chemistry, a US publication, shows that vegetarians and vegans are at a high risk of developing vitamin B12 deficiency.
Researchers from the Japanese institutions of Tottori University and the Junior College of Tokyo reviewed almost 100 different studies that researched into vitamin B12.
Despite the usual B12 dietary sources including eggs, milk, meat and fish, there are some foods derived from plants that are good sources of the vitamin such as fortified cereals or soyabeans.
Scientists have discovered that B12 is a bacteria and that the only living organisms that can create it are a specific bacteria that live in the digestive tract of animals. It can survive on or nears some plant types, but is usually lost when these are washed prior to consumption.
This latest study review has found that the human body cannot use the plant-based form of vitamin B12 so that vegetarians and vegans are both high risk for developing a deficiency.
Interestingly, this most recent study review shows that although there are dietary supplements of B12 available in stores, such as Spirulina - a blue-green algae - and some shellfish, this actually contains a "false" form of vitamin B12 that the human body is unable to use.
As part of the review study's conclusion, the scientists recommend that vegans and vegetarians eat fermented foods and certain varieties of mushroom such as Shiitake and Cremini, or vitamin B12-enriched vegetables.