Serum or plasma concentration of free fatty acids (unsaturated, medium-chain length)

Why This Test Might Be Ordered

Your healthcare provider may recommend this test if you have symptoms or conditions linked to abnormal fatty acid metabolism, such as unexplained fatigue, muscle weakness, or signs of metabolic syndrome. It could also be part of a broader evaluation for genetic disorders affecting fat metabolism, like carnitine palmitoyltransferase (CPT) deficiencies.

What to Expect Before the Test

No special preparation is typically needed, but you may be asked to fast for 8–12 hours before drawing blood. Avoid excessive alcohol or strenuous activity 24 hours prior. If you’re on medications that affect fats (e.g., statins), let your provider know.

What the Results Mean

Results show the concentration of specific free fatty acids in your bloodstream. Abnormal levels may indicate metabolic imbalances, genetic disorders, or other health concerns that require further medical evaluation.

Common Conditions Monitored

This test helps identify or track conditions like medium-chain acyl-CoA dehydrogenase (MCAD) deficiency, mitochondrial disorders, or other rare metabolic syndromes. It may also support diagnosis in patients with unexplained lipid abnormalities or fasting intolerance.