Vitamin B12 deficiency can potentially create extreme and irreversible damage, especially to the brain and the nervous system. At degrees just a little lower than regular, a variety of indicators such as weakness, melancholy, and shabby memory might be experienced. 1 However, these symptoms by themselves are too nonspecific to diagnose deficiency of the vitamin.
Vitamin B12 deficiency can additionally generate symptoms of madness as well as psychosis. Vitamin B12 deficiency can be caused by the metabolic disorder pernicious anemia.