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Vitamin B12

Vitamin B12 is needed for blood cell production, the nervous system and DNA. Deficiency can result from too little reliable B12 in the diet or, more often, an absorption problem. Symptoms are not specific, and nerve damage can occur without anaemia; have the cause and treatment established carefully instead of using high doses or injections long-term on your own initiative.

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Vitamin B12 is needed for blood cell production, the nervous system and DNA. Deficiency can result from too little reliable B12 in the diet or, more often, an absorption problem. Symptoms are not specific, and nerve damage can occur without anaemia; have the cause and treatment established carefully instead of using high doses or injections long-term on your own initiative.

  • Tiredness, pallor, breathlessness on exertion, palpitations or dizziness due to anaemia.
  • Tingling, numbness, burning feet, muscle weakness, unsteady walking or balance problems.
  • Include reliable B12 sources suited to your diet, such as animal products or plant-based products confirmed to be fortified; seaweed and fermented foods are not reliable substitutes.
  • If you eat a vegan diet, are pregnant or breastfeeding, or have an absorption problem, discuss prevention with a doctor or dietitian instead of waiting for symptoms.
  • Make an appointment for new tingling, unsteady walking, unexplained anaemia or persistent tiredness with a relevant dietary, medicine-related or surgical risk.
  • For urgent GP care outside normal opening hours, call HAP 9252. Call Ambulance 912 only for an immediately life-threatening situation.

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