An apparatus for defrosting or cooking foods, the apparatus including both radio frequency dielectric heating means and an induction heating means. The radio frequency dielectric heating means includes at least two electrodes positioned at a treatment zone, and a device for applying, between the electrodes, a difference in electric potential which is variable with a frequency between 1 MHz and 300 MHz. The induction heating means is electromagnetically coupled to at least one of the electrodes which is at least partly made of ferromagnetic material, such that the electrode transmits heat to the food.