Over the last several years, there has been an increase of several chronic diseases that are linked to dietary and lifestyle factors. Obesity, especially, is rising at an alarming rate in several countries. Due in part to increasing diet related health problems caused, among others, by obesity, nutritional labelling has been regarded as an important topic mainly because it can provide consumers with nutritional information that can be used to make informed and healthier food choices. A number of studies have focused on the empirical perspective of nutritional food label use. None of these studies, however, have focused on developing a theoretical economic model that would adequately describe nutritional food label use based on a utility theoretic framework. We attempt to fill this void by developing a simple theoretical model of nutritional label use in which we incorporate the time a consumer spends in reading food labels as part of his food choice process. The demand equations derived from the model are then empirically tested with data from a large-scale survey that was conducted in Athens, Greece from December 2005 to April 2006. Results suggest the significant role of several variables that flow directly from the theoretical model which, to our knowledge, have not been used in any previous empirical work. These results provide new insights that can be used as a segmentation tool by marketers.