Measures methylmalonic acid, a marker that rises when vitamin B12 levels are too low. Useful if you have B12-deficiency symptoms but a normal or borderline standard B12 result.
1 biomarker as listed by Medichecks.
Methylmalonic acid (MMA) is a substance that builds up in the blood when vitamin B12 levels are too low. Because it changes before standard B12 readings do, it is used as a more sensitive way to assess B12 status, particularly if you have symptoms such as fatigue, tingling in the hands and feet, or brain fog but your B12 test already came back normal or borderline.
This is a single-marker test, so clinical depth was never going to be its strength, and it scores accordingly against other vitamins tests we track. Where it falls down is value for money: at £149 it sits well above the £85 median for similarly sized vitamins tests, a gap wide enough to pull its overall score down. Collection is also less flexible than some Medichecks tests, since there is no at-home option; you need a venous draw at a clinic or a home nurse visit, with results back in around 10 days.
Where the test scores strongly is on documentation and trust: the listing sets out the sample type, turnaround and collection options clearly, and every result comes with a doctor's comment as standard. Medichecks also has a strong Trustpilot record and UKAS ISO 15189 partner labs, factors that lift its trust score even though this individual test comes at a premium price for a single biomarker.
This suits you if you already have a vitamin B12 result that came back normal or borderline but you are still getting symptoms like fatigue, tingling in the hands or feet, or brain fog, and you want a more sensitive follow-up marker. It is a narrow, single-purpose test rather than a broad health check, so it makes most sense as a next step after B12 testing rather than a first port of call.
If cost is a concern, be aware this is one of the pricier single-marker options in our vitamins category, and Medichecks does not offer a cheaper at-home version of this particular test. We do not have comparable single-marker MMA tests from other providers on file to compare it against directly. If your symptoms are ongoing or worsening, it is worth discussing them with a GP alongside this test.
This is a blood test collected by venous draw, either at a Medichecks clinic or via a home nurse visit; an at-home finger-prick option is not offered for this test. Once your sample reaches the lab it is processed for methylmalonic acid, and results are typically ready in around 10 days. Every result is reviewed and commented on by a doctor before you receive it.
This single-marker blood test measures methylmalonic acid, used to assess how well your body is using vitamin B12 when standard B12 results are normal or borderline. At £149 it costs well above the £85 median for similar single-marker vitamins tests we track, and there is no at-home collection option, only in-clinic or nurse-visit venous draws.
The listing publishes a short description, the full biomarker list, a stated turnaround, clear collection options, the sample type; it does not state what the report looks like.
1 biomarkers, placing it in the 31st percentile of vitamins tests we track.
A blood sample taken at home by a visiting nurse or phlebotomist; with a venous or clinic option as well; a home nurse visit is offered; results in around 10 days, slower than similar tests.
Results are reviewed by a doctor; the provider does not describe the report format.
Trustpilot 4.5 from 2,477 reviews; accredited lab (UKAS ISO 15189 partner labs); doctor review as standard; trading 25+ years.
£149.00 against a median of £85.00 for the 73 similarly sized vitamins tests we track (+75%).
Calculated 13 September 2026 from the facts we hold about this test and provider, using our published scoring formula. Scores are not hand-edited.
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