Serum or plasma substance concentration for free fatty acids (specifically medium-chain fatty acids)
This test measures certain types of fatty acids found in your blood, which can help assess metabolic health or detect conditions affecting fat metabolism.
["Understanding medium-chain fatty acids may aid in diagnosing or monitoring metabolic disorders."]
Key facts at a glance
- LOINC
- 41503-4
- Short code
- N men sg B Ag Fld Ql
- Synonyms
- N men sg B Ag Fld Ql
- 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 This Test Might Be Ordered
Your healthcare provider may recommend this test if you have symptoms or conditions linked to abnormal fat metabolism, such as unexplained weight changes, metabolic syndrome, or suspected fatty acid storage disorders. It could also be part of a broader evaluation for conditions like mitochondrial disorders or certain genetic metabolic diseases.
What to Expect Before the Test
No special preparation is typically required, but you may be asked to fast for 8–12 hours before the blood draw if your test involves fasting. Avoid excessive alcohol or certain medications that could affect fatty acid levels.
What Happens During the Test
A healthcare professional will draw blood from a vein in your arm. The blood sample will be sent to a lab for analysis, where fatty acid levels are measured using a specialized biochemical method.
What the Results Mean
Results provide a profile of medium-chain fatty acids in your bloodstream. Elevated or altered levels may indicate metabolic imbalances, while normal results suggest healthy fat metabolism. Your provider will interpret these results in the context of your overall health and symptoms.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Abnormal medium-chain fatty acid levels can signal underlying metabolic disorders, such as carnitine deficiency, mitochondrial diseases, or genetic conditions affecting fat breakdown. These conditions may require specialized treatment, dietary adjustments, or further diagnostic testing. Routine screening for MCFA is uncommon but may be part of a targeted evaluation for suspected metabolic disorders.
Short name
Medium-chain free fatty acids (MCFA) profile
Frequently asked questions
What does a high or low level of medium-chain fatty acids indicate?
Can diet or lifestyle changes affect medium-chain fatty acid levels?
Is this test covered by insurance?
Sources
- 1
- 2Lab Tests OnlineSource
- 3
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.
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