A simple blood test for the vitamin that supports red blood cells, energy, and nerve health.
Vitamin B12 (cobalamin) is a vitamin your body needs to make red blood cells, keep nerves healthy, and produce DNA. You get it from animal foods such as meat, fish, eggs, and dairy.
Your body cannot make B12, so it has to come from diet or supplements. It is stored in the liver, which is why a shortfall can take a long time to show up.
Low B12 can cause tiredness, tingling or numbness, memory problems, and a specific type of anaemia. It is common in people who eat little or no animal food, in older adults, and in those on certain stomach or diabetes medicines.
Catching low B12 early matters because some nerve damage can become permanent if it is left untreated for a long time.
Aniva reads your result against research-backed ranges, not just the lab's wide normal. The reference shown below is specific to this biomarker.
| Status | Serum B12 (SI) |
| Deficient | below ~150 pmol/L |
| Borderline | ~150 to 220 pmol/L |
| Sufficient | above ~220 pmol/L |
Ranges are guidance only and vary by lab and assay. Total B12 can miss early deficiency, so an active B12 (holotranscobalamin) or methylmalonic acid test is sometimes added. Read against your own lab's interval.
Recent B12 supplements or injections raise the number and can hide a true shortfall in the tissues. Pregnancy and some medicines (metformin, acid blockers, oral contraceptives) lower it. Biotin can interfere with some assays. No fasting needed.
Read alongside folate and a full blood count, and with methylmalonic acid or homocysteine when a result is borderline.
What do my Vitamin B12 results mean? A low result suggests limited intake or absorption. A high result often reflects supplements or recent injections; discuss next steps with your clinician.
Do I need to fast for this test? No. You can test any time of day unless your clinician gives different instructions.
What can affect my Vitamin B12 result? High‑dose biotin, recent B12 shots or large supplements, and testing soon after a dose can raise levels. Acid‑reducing medicines and metformin may lower B12 over time.
How often should I test Vitamin B12? If you are at risk or on treatment, retest every 3 to 12 months as advised. Otherwise, repeat only if symptoms or risk factors change.
How fast will I get results? Results are usually ready in about 7 days.
What should I discuss with my clinician? Share symptoms, diet (including vegan or low‑animal foods), and all supplements and medicines. Ask whether folate, methylmalonic acid, or homocysteine testing is helpful.
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