Cosmetic preparation having an aqueous phase, containing (a) creatine and/or creatinine (b) wherein the the aqueous phase contains one or more electrolytes selected from the group of salts having the following anions: chlorides, furthermore inorganic oxo-element anions, of these in particular sulphates, carbonates, phosphates, borates and aluminates, electrolytes based on organic anions, for example lactates, acetates, benzoates, propionates, tartrates, citrates, amino acids, ethylenediaminetetraacetic acid and the salts thereof and the following cations: ammonium, iron, copper, zinc, aluminium, alkylammonium, alkali metal, alkaline earth metal, in particular sodium, calcium and magnesium, ions; of water-soluble UV filters present as alkali metal salts, in particular those bearing one or more sulphonic acid groups or sulphonate groups on their molecular backbone; of amino acids and the salts thereof or the anions thereof; of cosmetically and dermatologically relevant α-hydroxycarboxylic acids, α-ketocarboxylic acids and β-hydroxycarboxylic acids and in particular the salts thereof, wherein the cations can be advantageously selected from the group of ammonium, alkylammonium, alkali metal, alkaline earth metal, magnesium, iron and zinc ions in a dissolved state, wherein the ionic strength of the aqueous phase in which the electrolyte(s) is/are present in a dissolved state is at least 0.050 mol/l and at least said aqueous phase has a pH of 6.2 to 7.8, particularly preferably 6.5 to 7.5. (a) creatine and/or creatinine (b) wherein the the aqueous phase contains one or more electrolytes selected from the group of salts having the following anions: chlorides, furthermore inorganic oxo-element anions, of these in particular sulphates, carbonates, phosphates, borates and aluminates, electrolytes based on organic anions, for example lactates, acetates, benzoates, propionates, tartrates, citrates, amino acids, ethylenediaminetetraacetic acid and the salts thereof and the following cations: ammonium, iron, copper, zinc, aluminium, alkylammonium, alkali metal, alkaline earth metal, in particular sodium, calcium and magnesium, ions; of water-soluble UV filters present as alkali metal salts, in particular those bearing one or more sulphonic acid groups or sulphonate groups on their molecular backbone; of amino acids and the salts thereof or the anions thereof; of cosmetically and dermatologically relevant α-hydroxycarboxylic acids, α-ketocarboxylic acids and β-hydroxycarboxylic acids and in particular the salts thereof, wherein the cations can be advantageously selected from the group of ammonium, alkylammonium, alkali metal, alkaline earth metal, magnesium, iron and zinc ions in a dissolved state, wherein the ionic strength of the aqueous phase in which the electrolyte(s) is/are present in a dissolved state is at least 0.050 mol/l and at least said aqueous phase has a pH of 6.2 to 7.8, particularly preferably 6.5 to 7.5. of salts having the following anions: chlorides, furthermore inorganic oxo-element anions, of these in particular sulphates, carbonates, phosphates, borates and aluminates, electrolytes based on organic anions, for example lactates, acetates, benzoates, propionates, tartrates, citrates, amino acids, ethylenediaminetetraacetic acid and the salts thereof and the following cations: ammonium, iron, copper, zinc, aluminium, alkylammonium, alkali metal, alkaline earth metal, in particular sodium, calcium and magnesium, ions; of water-soluble UV filters present as alkali metal salts, in particular those bearing one or more sulphonic acid groups or sulphonate groups on their molecular backbone; of amino acids and the salts thereof or the anions thereof; of cosmetically and dermatologically relevant α-hydroxycarboxylic acids, α-ketocarboxylic acids and β-hydroxycarboxylic acids and in particular the salts thereof, wherein the cations can be advantageously selected from the group of ammonium, alkylammonium, alkali metal, alkaline earth metal, magnesium, iron and zinc ions in a dissolved state, wherein the ionic strength of the aqueous phase in which the electrolyte(s) is/are present in a dissolved state is at least 0.050 mol/l and at least said aqueous phase has a pH of 6.2 to 7.8, particularly preferably 6.5 to 7.5.