What is the result of a deficiency in vitamin B12?

A deficiency in vitamin B12 leads to several critical health issues, primarily affecting the production of red blood cells and the proper functioning of the nervous system. This vitamin is essential for DNA synthesis, and without enough vitamin B12, the body cannot produce sufficient healthy red blood cells, which can lead to megaloblastic anemia. This type of anemia is characterized by the presence of large, structurally abnormal red blood cells that cannot function properly.

In addition to anemia, vitamin B12 is crucial for maintaining the health of nerve cells. A deficiency can result in nerve degeneration, which may manifest as numbness, tingling, or balance issues, due to the myelin sheath that protects nerve fibers being damaged. These two conditions, anemia and nerve degeneration, are directly connected to insufficient levels of vitamin B12, validating the choice that identifies both consequences as significant outcomes of this deficiency.