Secular trends in the prevalence of obesity in adults (BMI ³ 30 kg/m²) are described in the two more populated Brazilian regions: the less developed Northeast and the more developed Southeast. All data utilized by this study come from three nation-wide large-scale cross-sectional surveys undertaken in 1975, 1989 and 1997. In the first period (1975-1989), obesity increased uniformly for males and females in the two regions and both the excess of the disease in the Southeast and the inverse relationship between income and obesity, existing in the two regions, were not affected. The same situation was also observed for the male population in the second period (1989-1997) except for the relatively higher increase of obesity in the Northeast and the consequent reduction of the gap existing between the two regions. Trends in the prevalence of female obesity in the second period were distinctly influenced by income in the two regions. In the Northeast, increasing trends in female obesity were modest for lower income women and intense for intermediate and higher income groups. In the Southeast, there was a decline in the prevalence of obesity for intermediate and higher income groups and an intense increase for lower income women. These contrasting trends in the prevalence of obesity determined that, in 1997, except for the low income group, female obesity was more common in the Northeast than in the Southeast. The greater difference between the two regions as regard recent trends in obesity was seen for higher income groups (the 25% richest women in each region): a dramatic increase in the Northeast - from 9.9% to 14.6% - and a non less impressive decline in the Southeast - from 13.2% to 8.2%, The declining trends in obesity documented for women living in the Southeast of Brazil were not described yet in any other developing country. In fact, declining trends in obesity as those described in this study were reported, up to now, only for Scandinavian populations. Although much more in-depth analysis is needed, a plausible hypothesis to explain declining trends in female obesity in Brazil is that an intense mass media work focused on combating a sedentary life-style and promoting better food habits has been effective in reaching at least the higher income women in the more developed parts of the country.
Obesity; Income; Time trends; Developing countries; Brazil
