What are the symptoms of a vitamin b12 deficiency?

Yes.: Pernicious anemia is the most common reason for unexpected B12 deficiency. Lack of B12 can cause both anemia and neurological damage. The latter includes numbness, gait problems, and dementia. Anemia causes weakness. The neurological findings can occur before there is any anemia, or vice versa. The anemia will reverse with treatment. Neurologic changes may not correct.

Vit B 12 Deficiency: Lack of Vit B 12 can lead to Hypocobalaminemia. This can cause a slow degration of the spinal cord & brain. Problems may include: swollen tongue, anemia, sense of numbness & tingling in extremities, weakness, fatigue, problems walking, jaundice, depression, irritability, memory decline, cognitive dulling & eventually mania &/or psychosis.