What is the difference between SelenoExcell high selenium yeast and L-Selenomethionine?

High selenium yeast is generally a more superior, well-tolerated form of selenium than selenomethionine.

L-Selenomethionine is selenium bound to the amino acid methionine. SelenoExcell high selenium yeast is synthetic. High selenium yeast contains three organic selenium compounds (selenomethionine , selenocysteine and methylselenocysteine).  SelenoExcell originates from a non-pathogenic, non-GMO Saccharomyces cerevisiae (commonly known as "nutritional yeast") yeast strain. However, the S. cerevisiae cells in SelenoExcell are dead or inactive, and only the nutritional properties remain. The cells cannot reproduce in the human body when consumed because they are no longer alive.