Based on microeconomic consumer theory, this paper proposes a new methodology for the construction of poverty thresholds. The main objective is to show the composition of a non-food basket and its relationship with the food basket. Orshansky coefficients are estimated using a non-traditional method. For this purpose, a demand equations system aimed at estimating the subsistence baskets (food and non-food) is used. After solving for some econometric difficulties (simultaneity bias, identification and selectivity bias), this document analyses the system´s structural parameters. Minimum subsistence baskets for a population are obtained. Results refer to the population of Bogota and its districts.