Tag: Absorption

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Selenium from Selenium-Enriched Yeast

Selenium from selenium-enriched yeast supplements is more bioavailable than selenium from an inorganic source such as sodium selenite. Selenium from selenium-enriched yeast supplements also tends to be less toxic. These are the conclusions from a 2008 evaluation undertaken by a European Food Safety Authority (EFSA) scientific panel [EFSA 2008].

Glass of beer
Manufacturers use the yeast Saccharomyces cerevisiae — also known as brewer’s yeast — to produce selenium-enriched yeast supplements.

To quote directly from the report:

“Despite the higher bioavailability of selenium from organic sources such as selenium-enriched yeast, the toxicity of these organic forms has been shown in a number of studies in experimental animals to be lower than that of inorganic selenite or selenate.”

Study data indicate that organic selenium is more bioavailable than inorganic selenium. Studies in which different selenium preparations have been compared head-to-head point towards a higher bioavailability of selenium from yeast than from inorganic sources [Hadrup & Ravn-Haren 2021]. read more

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Selenoprotein P – Selenium Transport Protein and Biomarker of Selenium Status

Selenium and selenoproteins are essential to human health [Rayman 2012]. However, selenium intakes from food vary considerably from region to region in the world, depending on how rich or poor the soil and the foodstuffs are.

Selenium researcher Professor Urban Alehagen
Professor Urban Alehagen realized that the low selenium content of the soil in Sweden and in much of Europe results in wide-spread low dietary selenium intake and selenium deficiency. In the Swedish KiSel-10 Study, the average serum selenium concentration was a quite low 67 mcg/L.

For example, widespread suboptimal selenium status has been reported throughout Europe, the UK, and the Middle East [Stoffaneller & Morse 2015]. In contrast, the soil and the foodstuffs in much of the United States and Canada have a much higher selenium content than is the case in Europe. Serum selenium levels of US citizens are generally above 120 mcg/L. In many European countries, the corresponding serum selenium levels are 90 mcg/L on average [Alehagen 2016].

  • The best estimate for serum selenium status that is sufficient for good health is around 125 mcg/L [Winther 2020, fig. 3].
  • Serum selenium levels below 70 mcg/L are indicative of selenium deficiency [Bomer 2020].
  • Serum selenium levels below 100 mcg/L are indicative of sub-optimal selenium status [Al-Mubarak 2021].
Selenoprotein P as the Major Selenium Transport Protein

Dietary selenium is incorporated into the amino acid selenocysteine, which becomes an integral component of 25 selenoproteins. The best known selenoproteins are the glutathione peroxidases, thioredoxin reductases, and
iodothyronine deiodinases [Schomburg 2019]. read more