Methylmalonic Acid (MMA) Blood Test

Measures methylmalonic acid in serum.

Measures

Methylmalonic acid in serum.

Why it matters

MMA accumulates when vitamin B12 is insufficient at the cellular level, because B12 is required to process it. That makes it a functional marker — it describes whether B12 is doing its job, rather than how much is present.

It's typically ordered when a standard B12 result is borderline or doesn't match the clinical picture.

Before you collect

Note recent B12 supplementation or injections. Kidney function affects MMA independently of B12.

Suits

People with an unclear B12 result, working with a practitioner.

Your next step

Once you have your results, book with a Canwell naturopath, nutritionist or practitioner to talk them through and build a wellness plan that suits you. Book with Canwell