What is Vitamin B12 or Cobalamin + Food Sources of Vitamin B12 + Roles in the Body, Requirements and Deficiency and Toxicity

What is vitamin B12 or Cobalamin?

Tucked away in the central part of the vitamin B12 molecule is an atom of cobalt. Therefore molecules that have vitamin B12 activity have been named the cobalamins. Because vitamin B12 plays a role in activities that process energy nutrients, it holds its place on the roster of B-complex vitamins.

 

What foods provide this vitamin?

In the human diet, vitamin B12 is only found in foods of animal origin. Unlike animals, plants do not have a functional role for vitamin B12 and therefore do not make it. Interestingly, animals do not seem to make vitamin B12 either and rely instead upon their intestinal bacteria to make it. Vitamin B12 is then absorbed into that animal’s body from its digestive tract. The best sources of vitamin B12 are meats, fish, poultry, shellfish, eggs, milk, and milk products (see Vitamin B12 in Food Table). The vitamin B12 content in these foods is modest but compatible with our needs.