Asparagine Good Antioxidant Anti-Ageing Hydration Asparagine description Asparagine is a type of amino acid, fundamental constituents of all proteins found in the body. Some of amino acids can be synthesised by the body; others (known as essential amino acids) must be obtained from protein in the diet. In skin care products, amino acids act as water-binding agents, and some have antioxidant properties. Amino acids can be combined with other ingredients that have skin-restorative ability to work in unison to fight signs of ageing.