Are all the forms of Organic Selenium equivalent?

The development of new advanced analytical methods, by Vacchina et al., 2021, has allowed the additional selenium species in Seleno-Yeast (SeYeast) products to be further quantified. The new methods have revealed the presence of elemental selenium, an inorganic form of Selenium, in the tested SeYeasts. Consequently, analyses have shown that SeYeasts on average contain more inorganic selenium than previously believed and specified. The study has also confirmed the high variability of their selenomethionine content.