Vitamin B12 deficiency may result negative in hematological, neurological, and gastrointestinal conditions. The hematological systems and signs
of B12 deficiency include a decrease in red blood cell count, skin discolorations, decreased energy, fatigue, shortness of breath, and palpitations. Severe B12 deficiency can also result in anemia.
Even in the absence of anemia, the neurological effects of vitamin b12 deficiency can still occur. This is especially true for the elderly.