What is Vitamin B12? 

Vitamin B12 or cobalamin belongs to the group of water-soluble vitamins, which are not stored in the body and must be taken regularly through foods or supplements.  Vitamin B12 is not sensitive to heat. 

What is the role of vitamin B12?

Vitamin B12, or cobalamin, is involved in many amino acid conversions as well as in the formation of nucleic acids for RNA and DNA synthesis, and in fatty acids. It plays a key role in the formation of red blood cells and in the formation of bone marrow.

Which foods are rich in vitamin B12?

Vitamin B12, or cobalamin, is found in a wide variety of animal foods, although usually in small quantities. In particular, it is found in meat, fish, liver, milk and eggs.  

What is the daily requirement of vitamin B12?

The daily requirement of vitamin B12, or cobalamin, corresponds to approximately 2-2.4 mcg, the quantity recommended in a normal diet. Women who are pregnant, however, must retain twice as much in order to provide the fetus with the proper amount through maternal reserves.

Vitamin B12 deficiency

It is difficult to verify a situation involving lack of vitamin B12, or cobalamin, however, in some cases, a condition of this type may occur in individuals who follow a strict vegetarian diet or when the absorption mechanism of the intestine fails to work properly. 
Side effects of vitamin B12 deficiency include nervous system disorders and a form of anemia called pernicious, which is derived from a bad production of blood cells. Women are pregnant must steer clear of vitamin B12 deficiency in order to avoid harmful side effects to the fetus.  

Excessive Vitamin B12 intake

Normally, excessive vitamin B12 intake can be expelled from the body through urination. In rare cases, however, there may be situations where overdose of this vitamin can lead to symptoms ranging from tremors to swelling, nervousness, allergic reactions and a rapid heartbeat.  Through rare, an excess of vitamin B12 in the blood may lead to kidney problems.