WHAT IS GLYCINE? Glycine is the most abundant amino acid in the body; it is also involved in the transmission of chemical signals. Glycine is a non-essential amino acid & can be obtained from the diet via foods such as meat & fish. BULK POWDERS™ Glycine is of the highest quality. A quick glance at the Certificate of Analysis (COA) on this product page (to the side of the product image) details the high levels of purity. BENEFITS OF GLYCINE 100% Glycine