• Neurologic or motor symptoms
  • Mental status changes
  • Dementia or Alzheimer’s disease
  • Psychiatric disorders
  • Gastrointestinal disorders
  • Gastrointestinal surgeries
  • Gastric bypass
  • Anemia
  • Elevated MCV
  • Age 60 and over
  • Vegans
  • Vegetarians, macrobiotic diets
  • Autoimmune disorders
  • Developmental delay
  • Autism spectrum
  • Breast fed infants of mothers at risk
  • Eating disorders
  • Family history of pernicious anemia        
  • Proton pump inhibitor use
  • Metformin use
  • Occlusive vascular disorders (MI, CVA, DVT, PE)