The main component of green tea, EGCG(catechin), is composed of tannins and polyphenols. It is known to effectively improve skin damaged by UV rays. UV rays are the main cause of skin darkening and stimulate aging. Catechin suppresses the synthesis of the melanin pigment caused by UV rays and removes fresh radicals the promote aging, thereby helping to keep skin clearer. The light green tone of the serum is not an artificial color, but the natural color of the ingredients, so you can use it without worry.