Vitamin B12 is one of the most complex of all the vitamins. It is also called cobalamin, as it contains cobalt. The vitamin is got mainly from animal and dairy products like meat, poultry, milk, liver and fish. That’s the reason why vegans might fall short of sufficient stocks of vitamin B12. It is important for them to supplement their foods with vitamin B12.
Vitamin B12 is synthesized by the bacteria found in the digestive tract. Absorption of B12, from food, requires intrinsic factor. It is a secretion from the cells which line the stomach. Later B12 along with the intrinsic factor is absorbed in the small intestine. The lack of intrinsic factor in the stomach will lead to the deficiency of vitamin B12.
B12 plays a vital role in the formation of red blood cells and maintenence of a healthy nervous system. It is also important for synthesis of DNA, the genetic material. It is required in the bone marrow tissue, where the cells divide rapidly, to form red blood cells.
When there is deficiency of B12, abnormal cells called megaloblasts occur, which ultimately causes anemia. Megaloblastic anemia occurs when the red blood cells produced in the bone marrow do not shrink to the normal size. The deficiency of normal blood cells result in nerve damage. The nerve impulses are not carried properly resulting in numbness and the deactivation of the senses.
The lack of intrinsic factor causes pernicious anemia. Its symptoms are genral weakness, breathing problems, diarrhea, tongue inflammation, damage in the central nervous system, poor resistance to infection and menstrual problems.
A deficiency of vitamin B12 can also cause problems like loss of balance, depression and loss of memory. Some other symptoms are numbness and tingling sensation in the arms and legs and difficulty walking. Gastrointestinal symptoms include loss of appetite, sore tongue and constipation.
Though vitamin B12 deficiency is not very common, adults over the age of 60 years are the people who are at a higher risk of developing a deficiency. In infants, a deficiency of the vitamin can cause neural tube defects.
Deficiency of vitamin B12 can be treated with proper diet and supplementation. Supplementation, with at least 2 to 3 mcg per day, is especially important for vegans, who do not consume even milk and eggs.
People with anemia are treated with injections of vitamin B12. Oral supplementation of 1000 mcg per day is also a reliable alternative to injections.
For elderly people, 10 to 25 mcg per day, might proof to be beneficial. In some cases the dosage might go up to as much as 500-1000 mcg .
For therapeutic purposes, vitamin B12 is used as injectable to achieve optimum results.