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Selenium in Whole Blood, Mass Concentration

Published: August 9, 2026Updated: August 16, 2026

This test measures the amount of selenium, a trace mineral essential for overall health, found in your blood. Selenium helps protect cells from damage and supports immune function.

Quick summary

["Selenium levels help assess your body’s mineral balance and potential deficiencies or excesses."]

Medically reviewed by WellAlly Editorial TeamLast reviewed August 16, 2026Editorial policy

Key facts at a glance

LOINC
9483-9
Short code
Selenium Wat-mCnc
Synonyms
Selenium Wat-mCnc
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 Is This Test Done?

Your healthcare provider may order this test if you have symptoms of selenium deficiency (such as fatigue, muscle weakness, or immune issues) or if you have conditions that affect selenium metabolism (like certain kidney diseases or malabsorption disorders). It may also be part of routine screening or monitoring for selenium levels in specific populations.

What to Expect Before the Test

No special preparation is usually needed. You may be asked to fast for 8–12 hours before the test if it involves a blood draw, but this depends on the lab’s protocol. Bring any medications or supplements you’re taking to your appointment.

How the Test Is Performed

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 and typically painless. The blood sample is then sent to a lab for analysis.

What the Results Mean

Results are compared to general reference ranges for selenium in whole blood. Low levels may indicate deficiency, while very high levels could signal toxicity or other underlying health concerns. Your provider will interpret results in the context of your medical history and symptoms.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

Clinical Significance

Short name

Selenium Blood Level

Frequently asked questions

What Are Common Causes of Low Selenium Levels?
Low selenium levels can result from poor diet (low intake of selenium-rich foods like nuts, seafood, or whole grains), certain medical conditions (such as celiac disease or chronic kidney disease), or medications that interfere with selenium absorption.
What Are Common Causes of High Selenium Levels?
Excess selenium is less common but may occur from long-term high intake of selenium supplements, certain medications, or genetic conditions affecting selenium metabolism. Rarely, overconsumption of selenium supplements can lead to toxicity symptoms like nausea or hair loss.
How Often Should I Get This Test?
Your provider will determine the frequency based on your health status, symptoms, or risk factors. Routine adults typically don’t need this test unless recommended for specific conditions or monitoring.
  1. 1
    MedlinePlus — Laboratory TestsSource
  2. 2
    Lab Tests OnlineSource
  3. 3
    Mayo Clinic — Tests & ProceduresSource

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.

Medical Disclaimer

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