county of Avon, UK in 1991 and in the city of Pelotas, Brazil, in 1982 and 1993, population-based cohort studies were carried out providing the opportunity to investigate patterns of SEP-overweight status association among adolescents. The objectives of the present study were to investigate the association between overweight status and two indicators of SEP -- family income and maternal education -- among adolescents from the UK and Brazil, as well as to compare results between these populations.

Methods
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Avon Longitudinal Study of Parents and Children (ALSPAC)
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ALSPAC started during pregnancy and aimed to enrol all women living in the three Bristol-based health districts of the county of Avon and who had an expected date of delivery between April 1, 1991 and December 31, 1992. The study enrolled 14,541 pregnant women. Approximatelyinhabitants and more than 99% of all deliveries take place in hospitals. During the years of 1982 and 1993, birth cohort studies representing all births to mothers residing in the urban area of the city of Pelotas were carried out entailing primary data collection and using the same methodology. \[[@B14],[@B15]\] Births were assessed by daily visits to all maternity hospitals, totalling 5914 newborns in 1982 and 4231 in 1993. Mothers were interview soon after delivery with a structured questionnaire and newborns were weighted and measured. Non-response rates at recruitment were below 1% in both cohorts. The cohort members were followed up at several points in time.

### 1982 Pelotas cohort study

In 2000 and 2001 two follow-ups were carried out in the 1982 Pelotas cohort study. In 2000, male cohort