Vitamin B12 is a powerhouse vitamin. It helps make DNA and is crucial for healthy nerve function and healthy brain function.Vitamin B12 is an essential vitamin, which means we must ingest it. The body cannot manufacture this vitamin on its own.

The best source of Vitamin B12 is found in animal products like eggs, meat, fish and diary.

Vegetarians who by definition consume no animal products are at risk of B12 deficiency. Other people at increased risk for Vitamin B12 deficiency include atrophic gastritis, celiac disease, crohns disease and anyone who had gastric surgery.

There is a three-step process that occurs in order for the body to absorb Vitamin B12. 

After we ingest food that contains vitamin B12, gastric acid in the stomach is required to release the vitamin that is bound to the protein source. Once it is released, the vitamin B12 combines with a substance called Intrinsic Factor that is required for absorption.

Common symptoms of vitamin B12 deficiency include:

- Tingling hand and feet

- Muscle weakness

- Confusion

- Memory problems

Elevated Vitamin B12 level can be seen in liver disease, kidney disease, myeloproliferative disorders and other chronic diseases.