Abstract: Use in cosmetics of lipophilic derivatives of amino deoxyalditols, cosmetic compositions containing them, and novel alkyl carbamates.The invention is characterized by the use in cosmetic compositions of one or more lipophilic derivatives of amino deoxyalditols corresponding to the general formula: ##STR1## in which: R.sup.1 is a saturated linear C.sub.14 -C.sub.40 aliphatic radical;R.sup.2 is a hydrogen atom or a linear C.sub.1 -C.sub.6 alkyl radical;X is an oxygen atom or a methylene radical; andn is an integer from 1 to 5;with the proviso that when X is a methylene radical R.sup.1 contains from 19 to 39 carbon atoms.Application to the preparation of cosmetic compositions for the treatment of keratinous substances and for buccodental hygiene.