Selenium

Selenium is a component of 25 selenoproteins, among them glutathione peroxidase (GPX) and thioredoxin reductase – the most important antioxidant enzyme systems. It is indispensable for activating thyroid hormone (T4→T3) through selenoprotein deiodinase. Germany lies in a selenium-poor region – the soils contain little selenium, which is why selenium deficiency is more common here.

What selenium does in the body

Selenium is built into selenoproteins as the amino acid selenocysteine. The glutathione peroxidases use glutathione to neutralise hydrogen peroxide and lipid peroxides before they damage cell membranes. The deiodinases convert T4 into the active T3. The thyroid contains more selenium per gram than any other organ, because hydrogen peroxide is itself produced during hormone synthesis. Selenoprotein P carries selenium via the blood to the organs.

Low selenium – what happens in the body?

With little selenium, the glutathione peroxidases work more slowly: peroxides are broken down less well, oxidative stress in the cells increases and glutathione can exert its protective effect less. The conversion of T4 to T3 slows down, and the thyroid is more exposed to the hydrogen peroxide from its own hormone synthesis; studies have observed low selenium status more often in autoimmune thyroid disease. Immune cells also need selenium to respond to infections, and muscles including the heart muscle are sensitive to marked deficiency.

High selenium – what happens in the body?

The gap between adequate and excessive intake is comparatively small for selenium. Very high amounts (selenosis) show up as brittle nails, hair loss, garlic-like breath, skin changes and gastrointestinal complaints. High levels almost always result from high-dose supplements or very selenium-rich foods such as Brazil nuts.

The interpretation is given in your report.