Cosmetic additive for preventing poliosis and skin aging and preparation and application thereof

The invention provides a cosmetic additive prepared from selenium carrageenan, dihydrolipoic acid acid and L-methionine. The selenium carrageenan and the dihydrolipoic acid in a prescription are food additives, and the L-methionine is an amino acid necessary for human beings so that the cosmetic additive does not cause allergic reactions in human bodies and has strong repairing effect on human body cells. In addition, the prescription is used for not only effectively clearing oxygen free radicals, recovering the activities of tyrosinases and preventing the poliosis, but also reconstructing the functions of the protein and recovering the skin elasticity so that the cosmetic additive has optimal effects of preventing poliosis and skin aging.