Skip to content

Serum or plasma concentration of methylmalonic acid

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

This test measures the level of methylmalonic acid (MMA) in your blood, which helps identify certain metabolic disorders.

Quick summary

["MMA levels can signal vitamin B12 or folate deficiencies or genetic metabolic issues."]

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

Key facts at a glance

LOINC
50879-6
Short code
MEK Fld-sCnc
Synonyms
MEK Fld-sCnc
Category
chemistry
Sample
serum
Container
Red-top tube (SST)
Units
N/A
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
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 Is This Test Done?

Your doctor may order this test if you have symptoms like fatigue, weakness, nerve problems, or unexplained anemia. It’s also used to monitor conditions like vitamin B12 deficiency, methylmalonic aciduria, or other inherited metabolic disorders.

What Does a Result Mean?

Elevated MMA may indicate a problem with how your body breaks down certain fats or amino acids. Low levels might suggest vitamin deficiencies or genetic disorders. Your doctor will interpret results in the context of your symptoms and other tests.

Common Conditions Linked to MMA Levels

High MMA is often seen in vitamin B12 deficiency, pernicious anemia, or inherited disorders like methylmalonic aciduria. Low levels can occur in folate deficiency or certain genetic metabolic errors.

Sample Collection and Preparation

A blood sample is drawn from a vein in your arm. The test measures MMA in either serum (liquid part of blood after clotting) or plasma (liquid part after centrifugation). No special preparation is needed, but fasting may be advised depending on your doctor’s instructions.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

Clinical Significance

Short name

MMA (Serum/Plasma)

Frequently asked questions

What causes elevated MMA?
Elevated MMA can result from vitamin B12 or folate deficiencies, certain genetic disorders (like mutations in the MMA-CoA lyase or methylmalonyl-CoA mutase genes), or conditions that impair fat metabolism.
What causes low MMA?
Low MMA is less common but may occur in rare genetic disorders or in some cases of vitamin B12 deficiency when other markers are abnormal.
How often should this test be repeated?
Your doctor will determine follow-up timing based on your results, symptoms, and treatment plan. Repeated tests may be needed if you’re being treated for a metabolic disorder or monitoring a chronic condition.
  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