["Nutrition": a program to facilitate the calculations of the composition of menus and diets].

The methodology used to build a software program to compute the nutrient composition of menus and diets is discussed. Topics as the variability of food composition, the scarcity of local food composition data, the bias that may be incurred in nutrient data of food consumption studies are extensively discussed and also the possible solution through the software program. All of these topics must be taken into account in epidemiological studies as well as in computing diet composition.