Introduction: There are few population-based studies conducted in Brazil outside the major urban centers, the prevalence of overweight, obesity and associated factors in the up country cities remains not noticed. Particularly, the characteristics of this phenomenon are unknown in the mountain regions of Santa Catarina (state of the southern region), which concentrate the lowest economic and social development of the state, where culture, dietary habits and climate are quite peculiar. Objective: To estimate the prevalence of nutritional status and its association with self-reported diseases in adults of Lages, Santa Catarina. Methods: A cross sectional study including adults was conducted (n = 2022). Demographic information was collected as well as anthropometric measurements, through a number of interviews and physical examinations. The outcome of the study was the body mass index (BMI). The descriptive statistic was performed, as well as simple associations between BMI and the independent variables by sex. Correlations between BMI, abdominal circumference and self-reported diseases for men and women were tested separately. Results: The prevalence of normal weight, overweight and obesity among men was 41%, 39% and 19% respectively. Among women, the prevalence rates were 43%, 31% and 26%. It was observed that the obesity increase is correlated with low levels of education. The greater the BMI the more negative was the self-assessment of health. It was
found a positive correlation between BMI and abdominal circumference, with diabetes mellitus and high blood pressure levels. Conclusions: There was a high prevalence of overweight and obesity in Lages, SC. Strategies involving the various sectors of the community should be considered to reverse this process.