Vitamin B12 deficiency symptoms include:

  • Loss of appetite
  • Diarrhea
  • Numbness and tingling of hands and feet
  • Paleness
  • Shortness of breath
  • Fatigue (this is due primarily to the anemia)
  • Weakness (this is due primarily to the anemia)
  • Sore mouth and tongue
  • Confusion or change in mental status in severe or advanced cases. This is sometimes confused with dementia.