A brief discussión on "the social" approach in nutritional research is presented. The relevance that socioeconomic factors have acquired in recent years for this type of studies, is also discussed. The main purpose of our communication was to identify and validate some socioeconomic and environmental indicators and their association with the nutritional status of preschool children in a Mexican indigenous community (Sierra Norte de Puebla). A total of 89 children below five years of age were studied and classified according to their nutritional status. A socioeconomic questionnaire was applied to their parents. Results revealed ample correlation between the degree of malnutrition of the preschool child and the following indicators: housing conditions, father's main occupation, land tenure, income, etc. It is argued that the analysis of these indicators is relevant, emphasizing the importance that the combination of anthropometrical, food consumption and socioeconomic data have for detecting population groups vulnerable to malnutrition. The obtention of these indicators is therefore highly recommended, but should not imply great obstacles; on the contrary, they should be highly sensitive and easy to detect.