Overview of Vit B12
What is Vit B12?
Vitamin B12 test measures the levels of Vitamin B12 in blood. It plays an important role in the formation of healthy red blood cells, smooth functioning of the brain, and metabolism (processing) of carbohydrates, fats and proteins in the food. Vitamin B12 is said to be a micronutrient which means it is needed in very small amounts.
Why is Vit B12 done?
To diagnose anemia
To diagnose neuropathy (numbness and pain due to nerve damage)
To evaluate nutritional status
To monitor the treatment for Vitamin B12
What does Vit B12 Measure?
Vitamin B12 is a part of B complex of vitamins. Vitamin B12 is also called as Cobalamin. It is a water soluble vitamin. Vitamin B12 plays an important role in formation of normal red blood cells, repair of tissues, DNA synthesis and genetic material in cells. It is not produced in the body and has to be taken in diet. The diet sources include red meat, fish, milk, poultry, yoghurt, eggs, fortified cereals, breads and other grain products. It can also be taken in the form of Vitamin B12 tablets or multivitamin pills. The deficiency of Vitamin B12 results in macrocytic anemia (size of red blood cells larger than normal).
Megaloblastic anemia is a type of macrocytic anemia, in which large size red blood cells called as macrocytes are produced. These red blood cells are fewer in number. There is a decrease in white blood cell count and platelet count. Megaloblastic anemia occurs due to acquired deficiency of Vitamin B12. The reason can be an inadequate dietary intake of Vitamin B12 or any problem in the absorption of Vitamin B12 from the intestines.
In case of problem in the absorption of Vitamin B12 from intestines, it is known as Pernicious anemia. It occurs due to lack of intrinsic factor which is present in secretions of the stomach.
Vitamin B12 is also important for nerve health and is taken as a nutritional supplement for the treatment of nerve damage.
Vitamin B12 binds with intrinsic factor (protein secreted by cells in the stomach). After binding, a complex is formed which is absorbed by the small intestine. In case of any disease interfering in this process can cause weakening of absorption of Vitamin B12.
Preparation for Vit B12
- Do not eat or drink anything other than water for 8-12 hours before the test.
Sample Type for Vit B12
Interpreting Vit B12 results
The normal range is 211 - 911 pg/mL irrespective of sex and age.
High levels of Vitamin B12 may be seen in:
Low levels of Vitamin B12 may be seen in:
Hyperthyroidism (high levels of thyroid)