Vitamin B12 + Methylmalonic Acid (MMA)
The B12 level test measures B12 in the blood; an MMA test may be added, since a high MMA may be due to B12 deficiency. Some medicines affect the result.
The vitamin B12 level test measures how much B12 is in your blood, and a methylmalonic acid (MMA) test may be done with it to check for B12 deficiency. Some medicines, including metformin and proton pump inhibitors, can affect the B12 result.
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The B12 test has a partner, and a high result on it may point to low B12.
Transcript & sources → All videosMr. Age is AgeGen's editorial character. Facts come from the protocol above.
The biomarker
- Name: Vitamin B12 + Methylmalonic Acid (MMA)
- Units: B12 pg/mL; MMA µmol/L
- Standard reference range: B12 299–1054 pg/mL; MMA 0.07–0.27 µmol/L (per MedlinePlus; ranges vary by lab)
How to read your result
| Result | Interpretation |
|---|---|
| B12 < 299 | Possible sign of vitamin B12 deficiency, per MedlinePlus |
| MMA above range | May be due to vitamin B12 deficiency or methylmalonic acidemia |
| Medicines | Metformin, proton pump inhibitors, H2 blockers and several other medicines can affect the B12 result |
What moves the needle
- Diet. B12 occurs naturally only in animal foods; fortified cereals and nutritional yeast can supply it.
- Vegan diets. People on a vegan diet without eggs or dairy may need a B12 supplement — decide that with your clinician.
- Medicines. Tell your clinician about metformin, a proton pump inhibitor or other regular medicines.
- Testing. Ask whether an MMA test should be read alongside the B12 level.
Why this test is worth asking for
- A higher-than-normal MMA may be due to B12 deficiency, so the two tests give a second view of the same question.
- Several common medicines can affect the B12 result, which matters if you take any of them regularly.
- B12 occurs naturally only in animal foods, so diet is part of reading the number.
Related protocols
- Vitamin D — 25-Hydroxyvitamin D
- Zinc — Immune Mineral Status
- Urine ACR — Albumin-to-Creatinine Kidney Marker
Sources
AgeGen lab guides are educational only. We do not provide medical diagnosis, prescribe brands, or recommend specific doses. Talk to a licensed clinician before changing your supplement or medication routine.
