What it measures
Selenium is a trace element the body needs in small amounts, found in foods such as Brazil nuts, fish, meat and eggs. The test measures the amount in the blood, in plasma or in whole blood depending on the lab.
Why people test it
- Checked when intake may be low, for example on a restricted diet.
- Monitored in people on long-term feeding through a drip.
- Checked by people taking selenium supplements, since too much selenium can be harmful.
Typical range
Ranges vary by lab, method, age and sex, and plasma and whole blood results have different ranges; your report shows the lab's own range. Inflammation can lower plasma selenium.
Finger-prick or vein?
Taken from a vein, and providers offer it only as a vein draw. Ordinary needles and tubes can add traces of other elements, so labs use trace element tubes.
· 90 capsules · 90 servings · 200 µg a serving