Selenium Blood Level (Mass Concentration)

Your doctor may order a selenium blood test if you have symptoms of a deficiency, such as muscle weakness, fatigue, or hair loss, or if you have a health condition that affects how your body absorbs nutrients, such as Crohn's disease or kidney dialysis. The test may also be ordered to check for selenium toxicity if you have been exposed to unusually high levels of this mineral.

Your healthcare provider may recommend this test if you have symptoms like fatigue, hair loss, or muscle weakness, or if you have conditions like selenium deficiency or certain genetic disorders. It may also be used to monitor selenium levels in people with chronic illnesses or those taking supplements.

In most cases, no special preparation is needed for a selenium blood test. You can usually eat and drink normally before your appointment, but be sure to tell your doctor about any supplements or medications you are taking, especially selenium supplements, because they can affect your results. Follow any specific instructions your healthcare provider gives you before the test.

No special preparation is usually needed. You may be asked to fast for 8–12 hours before the test if it’s collected from serum or plasma. Bring any medications or supplements you’re taking to your appointment.

A healthcare professional will draw a small sample of blood from a vein, usually on the inside of your elbow or the back of your hand. The site is cleaned with an antiseptic, an elastic band is placed around your upper arm, and a needle is used to collect the blood into a tube. The procedure takes only a few minutes, and you may feel a brief sting when the needle is inserted.

A healthcare professional will draw blood from a vein in your arm using a small needle. You may feel a slight pinch, but the procedure is quick. The blood sample is then sent to a lab for analysis.

Normal selenium levels suggest that your body is getting an adequate amount of this essential mineral. Low levels may indicate a deficiency, which can result from poor nutrition, certain digestive disorders, or long-term dialysis. High levels may point to selenium toxicity, which is often caused by taking too many supplements. Your doctor will interpret your results together with your symptoms, medical history, and other test findings.

Results are compared to a reference range specific to selenium concentration in blood. Low levels may indicate deficiency, while very high levels could signal exposure to excessive selenium or certain medical conditions.