A process for producing a dispersion containing metal oxide nanoparticles in a liquid phase, wherein the process comprises the following steps: (a) atomization of a metal melt to give a metallic powder, (b) optionally deformation of the metallic powder obtained in step (a), (c) oxidation of the metallic powder obtained in step (a) or (b) to give a metal oxide powder, (d) comminution of the metal oxide powder obtained in step (c) in the presence of a liquid phase to give a dispersion whose metal oxide particles have a particle size d90,oxide of less than 300 nm. The invention further relates to a dispersion which can be obtained by the process of the invention.