Zinc, Serum Concentration

Why Is This Test Done?

Your healthcare provider may order this test to check for zinc deficiency, which can cause symptoms like hair loss, frequent infections, or poor wound healing. It may also be used to monitor zinc levels in people with certain medical conditions, such as chronic illnesses or malabsorption disorders (e.g., celiac disease). Rarely, it could be part of a broader evaluation for unexplained symptoms like fatigue or weakness.

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 test if it’s part of a metabolic evaluation. Bring any medications or supplements you’re taking, as they could affect results. Avoid consuming zinc supplements or foods high in zinc (e.g., nuts, seeds) for 24 hours before testing.

How the Test Is Performed

A blood sample is drawn from a vein in your arm by a healthcare professional. The serum portion of the blood is then analyzed in a lab to measure zinc concentration using a specialized method (often immunoassay or chemiluminescent immunoassay). The result is reported in micrograms per deciliter (mcg/dL) or milligrams per deciliter (mg/dL).

What the Results Mean

Results are compared to a reference range specific to your age, sex, and health status. Low zinc levels may indicate deficiency, while very high levels (rare) could signal medical conditions like acute liver disease or certain genetic disorders. Your provider will interpret the result in the context of your overall health and symptoms.