Also known as cobalamin, vitamin B12 is an extremely essential vitamin. It is important for the production of DNA and red blood cells. Additionally, it helps in effective functioning of your nervous system. Found in foods like eggs, meats, dairy products etc. this water-soluble vitamin can be helpful in keeping you healthy. Deficiency of cobalamin in the body can affect your health in many ways. It is characterized by symptoms like fatigue, weakness, sensation of pins and needles, breathlessness etc. Vitamin B12 deficiency is most commonly found in elderly people. Also, those who have had surgery where their bowel part was removed, people on drug metformin, those following a vegan diet etc. are at increased risk of developing this condition. The main reason for the symptoms you experience due to deficiency of this vitamin is that it causes lack of healthy blood cells in the body. If not taken care of on time, you may go through certain complications. Read on to know about them.