L-lysine hydrochloride

L-Lysine is an essential amino acid in human nutrition because the body cannot produce it; therefore, it must be taken in either by diet or supplementation. L-Lysine was first isolated from casein (a milk phosphoprotein) in 1889. It was first introduced in the United States as L-Lysine hydrochloride in 1955. There was an interest in fortifying bread with L-Lysine to target populations with L-Lysine poor diets. However, the FDA refused to modify the standards of identity for white bread. Since 1970, L-Lysine has been commonly added to animal feed.