[Overweight, obesity and associated factors in first grade schoolchildren in a city of the metropolitan region of São Paulo, Brazil].

This study assessed the prevalence of overweight in public school first graders and the association between overweight and socio-environmental factors in a city in Greater Metropolitan São Paulo, Brazil. Children enrolling in public school first grade in Cajamar in 2005 were assessed. Overweight was defined according to body mass index, by gender and age. Socio-environmental information was obtained using a questionnaire applied to 58.6% of the children's mothers. Poisson regression models were used to evaluate associations between overweight in schoolchildren and socio-environmental variables. Seventeen percent of the children were overweight. Factors associated with overweight were: mother's obesity (PR = 3.54; CI: 2.16-5.80), high consumption of junk food (PR = 2.12; CI: 1.30-3.45), more than 4 hours a day watching TV (PR = 2.08; CI: 1.03-4.20), and daily household per capita availability of vegetal oil (around 3 tablespoons) (PR = 1.52; CI: 1.01-2.31). The family environment has a strong influence on overweight in children entering first grade in public schools. Prevention of childhood overweight should preferably target the parents and other caregivers.