Objective To analyze the time trend of sociodemographic characteristics and the prevalence of food consumption, overweight, and obesity variables among adults in the city of Belo Horizonte, Brazil, between 2006 and 2018. Methods A time series study involving data from the Sistema de Vigilância de Fatores de Risco e Proteção para Doenças Crônicas por Inquérito Telefônico (Vigitel, Surveillance System of Risk and Protective Factors for Chronic Diseases by Telephone Survey), between 2006 and 2018 in Belo Horizonte (n=25,443). The annual prevalence of the population’s sociodemographic characteristics (sex, age groups, and years of schooling), and risk and protective factors for chronic diseases related to food consumption and nutritional status were estimated. Prais-Winsten regression models were used to investigate the temporal variation of each variable. Results From 2006 to 2018, there was a significant increase in the age and educational level of the adult population of Belo Horizonte. In the same period, the prevalence of recommended consumption of fruits and vegetables increased (from 23.0% to 29.2%), while that of consumption of fat-rich meat and regular consumption of soft drinks decreased (respectively, from 41.9% to 38.0%; from 35.3% to 15.2%). In parallel, the prevalence of overweight and obesity increased (respectively, from 38.5% to 53.3%; from 9.8% to 17.2%). Conclusions An important change in the population’s sociodemographic profile was noted. There are also favorable changes regarding the investigated aspects of food consumption, without these being sufficient to prevent the significant increase in the prevalence of overweight and obesity in the population.