Alpha amino acids are the building blocks of proteins. The structures of all the alpha amino acids include a carboxylic acid with an amine (NH2) group on the adjacent carbon. The 20 most common amino acids found in proteins are: Alanine, Arginine, Asparagine, Aspartic Acid, Cysteine, Glutamic Acid, Glutamine, Glycine, Histidine, Isoleucine, Leucine, Lysine, Methionine, Phenylalanine, Proline, Serine, Threonine, Tryptophan, Tyrosine and Valine. The amino acids and simple salts of amino acids, such as Arginine HCl, Calcium Aspartate, Calcium Glycinate, Cysteine HCl, Dipotassium Aspartate, Histidine HCl, Lysine HCl, Magnesium Aspartate, Magnesium Glycinate, Potassium Aspartate, Sodium Aspartate, Sodium Glutamate and Sodium Glycinate may be used in cosmetics and personal care products. Products in which these ingredients may be found include baby products, bath products, cleansing products, eye makeup, shaving preparations and hair and skin care products.