Selenium is an essential trace element which cannot be built by the body's own metabolism. Therefore - like vitamins - it has to be supplied from outside. For a long time, selenium, however, had been considered as toxic. Only in 1957, the German physicians Schwartz and Foltz could provide evidence of the essentiality of the substance (protection from liver necrosis in rats as test animals). Selenium is a micro trace element since it is needed only in very low doses, in microgram (µg).
In the meantime, extensive medicinal and biological meanings are attributed to selenium, for example for the function of the immune system and the thyroid, for the protection of the cells from oxidative damages, for the maintenance of hair and nails and production of sperm.
With Cefasel, Cefak introduced selenium already in 1984 in Germany – as first pharmaceutical manufacturer – in the pharmaceutical therapy.
Today, selenium is in the focus of science, the selenium research is really booming as it is shown by the nearly daily appearing new scientific publications.
|1818||Berzelius (Sweden) discovers and names selenium|
|1935||Selenium intoxication in cattle by fields on very selenium-rich soils in the USA|
Proof that liver necrosis of the rat can be prevented by addition of selenium|
Essential trace element for rats
|1969||Inverse correlation between cancer mortality and Se-contents in forage crops|
|1970||Experimental proof that selenium is essential for numerous animal species|
|1973||Selenium as component of the glutathione peroxidase of different animal species|
|1996||Chemopreventive properties of selenium in large human study confirmed (Clark et al., 1996)|
|until 2002||Selenoproteins with known enzyme function: GPx, TRxR, Dio|
Human: 25 genes
Rodent: 24 genes
Drosophila: 4 genes
C. elegans: 1 gene
to date more than 25 selenoproteins known
It can be assumed that further selenoproteins and important physiological functions of the essential trace element selenium will be discovered in the next few years.