Vitamin B12
EFSA/clinical: deficiency (common on a plant-based diet) causes anemia and neurological problems.
| Rating | Range |
|---|---|
| Talk to a doctor | below 133 pmol/L |
| Worth improving | 133 – 258 pmol/L |
| Good | 258 pmol/L and above |
Why it matters
EFSA/clinical: deficiency (common on a plant-based diet) causes anemia and neurological problems.
If it’s low
Low B12 means a risk of anemia and nerve damage (tingling, balance, concentration, mood). The causes are often poor absorption, not just diet.
If it’s high
High B12 (without supplements) is less often significant, but can accompany liver or blood diseases — interpret in context.
What to do
Low: sources of B12 (meat, eggs, dairy) or a supplement; with veganism, supplement regularly. Find the cause of poor absorption if diet is not to blame.
Read together with
Folate · Hemoglobin · MCV · Homocysteine
Part of the guide: Vitamins & minerals →
Articles about this marker
- Blood test reference values — table by test for adultsReading your report
- Blood tests before pregnancy: what to check before you conceiveLife stages
- Fatigue: which blood tests explain it — and which don'tSymptom → test
- High homocysteine: what it means and how to lower itMarker explained
- High RDW: what red cell distribution width means on your blood testComplete blood count (CBC)
- MCV, MCH and MCHC: what high and low red cell indices meanComplete blood count (CBC)
This content is for information only and is not a substitute for medical advice. Talk to your doctor about your results.
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