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Methylmalonic Acid (Serum/Plasma)

Published: August 9, 2026Updated: August 16, 2026

This test measures the level of methylmalonic acid (MMA) in your blood. MMA is a breakdown product of certain amino acids and can indicate metabolic issues.

Quick summary

["High levels may signal vitamin B12 or folate deficiency or other metabolic disorders."]

Medically reviewed by WellAlly Editorial TeamLast reviewed August 16, 2026Editorial policy

Key facts at a glance

LOINC
35950-5
Short code
MR TA
Synonyms
MR TA
Category
chemistry
Sample
serum
Container
Red-top tube (SST)
Units
N/A
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
Method
mr
Specimen volume
5 mL
Stability
Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
Hemolysis max
500
Lipemia max
1000
Icterus max
500
TAT
4–24 hours
Order
routine

Why Might This Test Be Ordered?

Your healthcare provider may order this test if you have symptoms like fatigue, weakness, or neurological problems, or if you have conditions like vitamin deficiencies, kidney disease, or inherited metabolic disorders. It’s also used to monitor certain treatments.

What Does the Test Measure?

MMA is produced when your body breaks down certain amino acids. Elevated levels can suggest problems with how your body processes these nutrients, which may involve vitamin deficiencies or genetic disorders.

Sample Collection and Preparation

A blood sample is taken from a vein in your arm. The sample is sent to a lab for analysis. You may be asked to fast before the test, depending on your provider’s instructions.

Common Causes of Abnormal Results

High MMA levels are often linked to vitamin B12 or folate deficiency, kidney disease, or inherited metabolic disorders like methylmalonic aciduria. Low levels are less common but may occur in rare genetic conditions.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

Clinical Significance

Short name

MMA

Frequently asked questions

If your MMA levels are high, it can help diagnose or guide treatment for conditions like pernicious anemia, certain types of kidney disease, or metabolic disorders. Follow-up tests or treatments may be recommended based on the results.
This test alone may not provide a definitive diagnosis. Your provider will consider your symptoms, medical history, and other test results when interpreting the results.
What should I do if my MMA levels are abnormal?
If your results are outside the expected range, your healthcare provider will discuss them with you. They may recommend additional tests, changes to your diet, or other treatments to address the underlying cause.
Can diet affect MMA levels?
Diet alone typically doesn’t directly affect MMA levels, but managing underlying conditions like vitamin deficiencies or kidney disease through diet and medical care can help control levels.
  1. 1
    MedlinePlus — Laboratory TestsSource
  2. 2
    Lab Tests OnlineSource
  3. 3
    Mayo Clinic — Tests & ProceduresSource

Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.

This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.

Medical Disclaimer

This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.

If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.

Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy