Generally, less developed countries have few funds for the gathering of nutritional data. Normally it is easier to obtain funds for gathering economic information. To obtain nutritional data, we propose using an economically oriented survey, the household budget survey, carried out in almost every country to indirectly estimate the dietary intake of low income urban families. We describe here the methodology used, the advantages and limitations of utilizing this kind of survey for nutritional purposes and finally we present some results of a study we carried out with the methodology proposed.