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Methylmalonic Acid, Serum

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

This test measures the level of methylmalonic acid in your blood, which helps assess how well your body is breaking down certain foods and using vitamin B12.

Quick summary

["Methylmalonic acid levels can indicate vitamin deficiencies or metabolic issues."]

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

Key facts at a glance

LOINC
36796-1
Short code
MRA LE ves-R
Synonyms
MRA LE ves-R
Category
chemistry
Sample
serum
Container
Red-top tube (SST)
Units
N/A
Ref low
0
Ref high
20
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
Method
mr-angio
CPT
85651
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 to check for conditions like vitamin B12 deficiency, pernicious anemia, or other metabolic disorders that affect how your body processes certain nutrients. It’s also useful in diagnosing inherited metabolic diseases or evaluating patients with unexplained symptoms like fatigue, weakness, or neurological problems.

What Does a High or Low Level Mean?

High levels of methylmalonic acid may suggest vitamin B12 deficiency, mitochondrial disorders, or genetic metabolic disorders. Low levels might indicate vitamin B12 deficiency or other metabolic issues, though this is less common. Your doctor will interpret results in the context of your overall health and other test findings.

How Is This Test Performed?

A blood sample is taken from a vein in your arm. The blood is then sent to a lab where it is analyzed to measure methylmalonic acid levels using a specialized chemical test.

What Should You Do Before the Test?

No special preparation is usually needed, but your doctor may advise you to avoid certain foods or medications that could affect results. Follow any instructions they provide, such as fasting or timing of the test.

Reference range

Adult males: 0-15 mm/hr; Females: 0-20 mm/hrN/A

Specimen: serum

No special preparation required. CRP may be affected by acute illness.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

◆Associated findings1

Short name

MMA (Serum)

Frequently asked questions

What are the normal results for this test?
Normal results vary by lab and may not have a single standard range. Your doctor will compare your results to your own baseline or to ranges appropriate for your age and health status. High or low levels may prompt further testing, such as vitamin B12 and folate levels, to identify underlying causes.
Can diet or supplements affect this test?
Yes, certain foods and supplements, like vitamin B12 or folate, can influence methylmalonic acid levels. If you take supplements or have dietary restrictions, let your doctor know so they can account for these factors in interpreting your results.
How often should I get this test?
The frequency depends on your health condition and doctor’s recommendations. If you have a known metabolic disorder or vitamin deficiency, your doctor may schedule regular follow-up tests. Otherwise, this test is typically ordered as needed for specific symptoms or investigations.
  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