The invention regards a medical apparatus made up of at least two devices (30, 32) adapted to measure eating rate utilized to teach persons to eat according to a predetermined graphic eating curve (10, 24) displayed on a screen, and a method therefore. There are means in a memory automatically calculating equations for predetermined eating curves (10, 24) based on data obtained from a cumulative food intake in a control meal through an introductory curve followed by training curves. The cumulative food intake is fitted to a quadratic equation y=ax
