This vitamin is in charge to maintain a healthy nervous system and normal blood production. It is also a key (along with folic acid and vitamin B6) to maintain a healthy circulatory system. What matters is the daily intake of these substances.
It is true that only animal products contain this vitamin. A wide range of foods is enriched with vitamin B12. For example, yeast, margarine, soy milk, different kinds of juices, cereals, soy products.
You can also use supplements to make sure you’re getting your daily needs for this vitamin.