✍️ Edited by Farhan Ahmed, Editor, MedTestBD · Last updated: August 2026
What is the Vitamin B12 Test?
The Vitamin B12 test (also called the cobalamin test) measures the level of vitamin B12 in your blood. Vitamin B12 is essential for producing red blood cells, maintaining a healthy nervous system, and supporting DNA synthesis. The body cannot make B12 on its own — it must come from animal-based foods or supplements. Deficiency is surprisingly common, especially among vegetarians, the elderly, and people with digestive conditions.
Why is the Vitamin B12 Test Done?
- To diagnose B12 deficiency, which can cause anaemia and nerve damage if left untreated
- To investigate symptoms like tingling or numbness in hands and feet, memory problems, or extreme fatigue
- To evaluate macrocytic anaemia — abnormally large red blood cells often caused by B12 or folate deficiency
- To monitor patients on long-term metformin (a diabetes drug that reduces B12 absorption)
- To assess B12 status in vegetarians, vegans, elderly patients, or those with stomach or intestinal conditions
Normal Vitamin B12 Levels
| Status | B12 Level |
|---|---|
| Deficient | Below 200 pg/mL (148 pmol/L) |
| Borderline / Low-normal | 200 – 300 pg/mL |
| Normal / Sufficient | 300 – 900 pg/mL (221 – 664 pmol/L) |
Values between 200–300 pg/mL are borderline — your doctor may order additional tests (such as MMA or homocysteine) to confirm true deficiency. Symptoms can appear even with borderline levels.
How to Prepare for the Vitamin B12 Test
- No fasting is usually required, though some labs prefer a fasting sample
- If you take B12 supplements or injections, inform your doctor — you may be asked to hold them before the test to get an accurate baseline
- Inform the lab about any multivitamins or nutritional supplements you take regularly
- A simple blood sample is drawn from a vein in your arm
Vitamin B12 Test Price in Bangladesh
Vitamin B12 test prices vary between diagnostic centers across Bangladesh. Compare Vitamin B12 test prices on MedTestBD →
Normal ranges cited on this page are based on MedlinePlus and WHO guidance. Prices are collected from public sources and may change — confirm with the facility before visiting. This information is for general reference only and is not medical advice. Always consult a qualified physician.
