Amino acids are organic compounds containing an amine (-NH2) and carboxyl
(-COOH) functional groups, along with a side chain (R group) specific to each amino acid. The key elements of an amino acid are carbon (C), hydrogen (H), oxygen (O), and nitrogen (N), although other elements are found in the side chains of certain amino acids. Amino acids are the building blocks of proteins.
There are 2 groups of amino acids, essential and non-essential. Out of the twenty amino acids nine are considered essential the body cannot manufacture them, they must come from diet. The body can manufacture the non-essential amino acids from the by-products of carbohydrate metabolism.