vitamin b12 is supplied mostly in
Other excellent sources of Cobalamin are eggs, milk and dairy products, fish, shellfish and poultry. Vitamin B12 can also be obtained from fortified foods. Vitamin B12 deficiency is usually caused by anemia and mostly produces extensive damage to the brain and nervous system.Symptoms of vitamin B12 and vitamin B9 deficiencies overlap because they are caused by pernicious anemia.Therefore, vitamin B12 supplements are usually given to treat this deficiency.owever, because of the low toxicity of this vitamin, that dose can be exceeded with no side effects. Vitamin B12 is mostly produced by bacteria. Therefore, plant and animal sources of the vitamin are usually taken from the parts where bacteria mostly grow. For animals, this part is the gut.