Low density cosmetic formulations which comprise: (a) a cosmetic mixture and (b) a gas incorporated in the cosmetic mixture wherein the cosmetic mixture comprises (i) an alk(en)ylpolyglycoside, (ii) a quaternary ammonium polymer, and (iii) a thickener, are described along with suitable cosmetic mixtures for forming such low density formulations, methods of forming such formulations and methods of cosmetic treatment of skin, hair, nails and/or combinations thereof by contacting the skin, hair and/or nails with such formulations and/or products containing such formulations.