Abstract: An instrument, preferably hand-held and hand-operated, for quickly and efficiently assisting in the determination of important nutritional information, such as the percentage of protein, fat and carbohydrates consumed during a given period of time, as well as the total calories consumed. The instrument may preferably operate in accordance with the principle of "food exchanges" and may also preferably include a capability for precise numerical entry of various nutritional quantities. In accordance with at least one preferred embodiment of the present invention, the instrument may be shaped in the manner of a "food pyramid" and contain sections reminiscent of the sections of a typical "food pyramid".