Detergent cosmetic compositions containing an anionic surfactant derived from amino acids and salts thereof and a silicone and uses thereof

Novel cosmetic compositions comprising, in a cosmetically acceptable medium, (a) at least one anionic surfactant chosen from N-acylated compounds of mono- and poly-amidated polycarboxylic amino acids and the salts of said acids and (b) at least one silicone. This combination can impart at least one cosmetic property (such as sleekness, lightness, softness) without keratinous fibre regreasing phenomenon. These compositions are used, for example, for washing and/or conditioning keratinous materials such as the hair or the skin.