Long-chain alkyl cyclic acetals made from sugars are obtainable by a method that comprises the steps consisting of: dehydrating a hexitol in a monoanhydrohexitol substrate; reacting the monoanhydrohexitol substrate obtained with an alkyl aldehyde reagent containing 5 to 18 carbon atoms, by means of an acetalization reaction with a substrate/reagent ratio of between 5:1 and 1:1, or with a derivative of an alkyl aldehyde reagent containing 5 to 18 carbon atoms, by means of a transacetalization reaction with a substrate/reagent ratio of between 1:1 and 1:3, in the presence of acid catalyst and in an environment that is free of solvent or that consists of non-aqueous polar solvent; collecting the long-chain alkyl acetal of hexitan from the mixture obtained.