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Vitamin B12 (Cobalamin)
Abbreviation: B12
Panel: Vitamin & Mineral Tests · All vitamins & minerals tests
Typical adult reference range
| Conventional units | 200–900 pg/mL |
| SI units | 148–664 pmol/L |
Ranges vary between laboratories and methods — compare your result with the range printed on your own report.
What a high or low result can mean
High vitamin b12 (cobalamin): high values can be seen after supplementation and in some liver or blood disorders.
Low vitamin b12 (cobalamin): low values may occur with pernicious anemia, vegan diet without supplementation, malabsorption, or metformin use.
These are associations, not a diagnosis: the same result can have several causes, and your clinician interprets it with the rest of your results and history.
Good to know
Borderline results are sometimes clarified with methylmalonic acid or homocysteine.
Related tests — Vitamin & Mineral Tests
Please note: Reference ranges vary between laboratories, and between the methods and instruments they use — the range printed on your own report is the one your result should be compared with. A result outside the range is not by itself a diagnosis, and a result inside it does not rule out illness. These pages are an educational summary, not medical advice: always discuss your results with the clinician who ordered them, who can interpret them in the context of your health and history.