The aim of the study is the presentation and validation of a computer program, GRUNUMUR, designed for nutritional evaluation studies in great population groups, and to describe some of the results obtained after the application of this working tool. This program includes he following types of studies: a) dietary study; b) food habits study; c) anthropometric study and d) clinical study. The main advantage of GRUNUMUR is the possibility of being periodically actualized without any important software knowledge, and to be opened to the introduction of new data bases. The software program GRUNUMUR Is one more of the multiple programs described in the literature. However, once validated, this tool has the particularity of being developed after an important experience in the nutritional field and only with a scientific purpose. The result is a reliable tool, which facilitates nutrition research.