Abstract

This study was to investigate the temporal evolution of body mass index (BMI) in young enlisted men of 18 years in Brazil between 1980 and 2005, to identify specific points of greatest variance in time series and compare specific points in time, and the temporal evolution of BMI with socioeconomic changes in Brazil. The present study explores a temporal series of twenty-six national surveys of Brazilian men enlisted between 1980 and 2005. Heteroscedasticity in BMI time series was tested using Engle’s Lagrange-multiplier (LM) test, and analyses were performed using the autoregressive conditional heteroscedasticity (ARCH) model. As possible explanations for these increases in mean BMI, changes in economic indicators were considered. Particularly in 1985 to 1986 and 1994 to 1995, there was a sharp and significant increase in BMI. These two points occurred after two major economic policy changes that increased the purchasing power of the population related to economics factors such as: reducing the level of social inequality, increased family income, poverty reduction, inflation control, and increased consumption of foods. The present study showed a sharp increase of obesity in the population of young men in Brazil on two occasions during this series (years 1985 to 1986 and 1994 to 19955), when a possible reduction in caloric expenditure and increased food consumption population were observed.

Key words: Temporal trends, body mass index, obesity, Brazil.