Disclosed are uses of rare earth element selected from the group consisting of cerium (Ce), praseodymium (Pr), promethium (Pm), europium (Eu), terbium (Tb), dysprosium (Dy), holmium (Ho), erbium (Er), thulium (Tm), ytterbium (Yb), scandium (Sc), yttrium (Y), lanthanum (La), neodymium (Nd), samarium (Sm), gadolinium (Gd), ruthenium (Lu) and mixtures thereof, or a salt or an oxide thereof for preventing hair loss, promoting hair regrowth and hair growth, removing and preventing dandruff, or promoting black hair formation.