Serum or plasma concentration of vitamin E (alpha-tocopherol)

Why Is This Test Done?

Your healthcare provider may order this test to check for vitamin E deficiency, which can occur due to poor diet, certain medical conditions, or malabsorption issues like Crohn’s disease or celiac disease. It may also be used to monitor treatment for conditions like cystic fibrosis or liver disease. Rarely, it could be part of a broader evaluation for neurological symptoms, such as nerve damage or muscle weakness, if other causes are unclear.

What to Expect Before the Test

No special preparation is usually needed, but you may be asked to fast for 8–12 hours before the blood draw if your test involves a fasting sample. Avoid taking vitamin E supplements or multivitamins for at least 24 hours before testing, as they can affect results.

What Happens During the Test?

A healthcare professional will draw blood from a vein in your arm. You may feel a slight pinch, but the process is quick. The blood sample will be sent to a lab for analysis using an immunoassay method to measure vitamin E levels.

What Are Possible Results?

Results are typically reported as a concentration in milligrams per deciliter (mg/dL). Low levels may indicate deficiency, while very high levels could suggest overconsumption of supplements or certain medications. Your results will be interpreted by your provider in the context of your overall health.