To determine whether household food insecurity (HFI) is associated with a higher prevalence of excessive weight (EW) in a large random sample of Brazilian female adolescents.

Nationally representative cross-sectional study. EW was the outcome variable (BMI ≥ 85th percentile of WHO reference for adolescents aged 15–18 years and BMI ≥ 25 kg/m2 for those aged 19 years). HFI was measured with the Brazilian Food Insecurity Scale. Associations were measured using crude and adjusted prevalence ratios (PR) with 95 % confidence intervals through Poisson regression models taking into account the complex sampling design.

Data were derived from the third wave of the Demographic and Health Survey conducted in 2006–2007, in Brazil.

The sample included 1529 female adolescents aged 15–19 years.

The prevalence of any level of HFI was 40·8 %, with 26·6 % of households experiencing mild, 9·4 % moderate and 4·8 % severe food insecurity. The overall prevalence of EW was 21·9 % (12·9 % were overweight and 9·0 % obese). EW prevalence among those living in severely, moderately and mildly food-insecure households was 36·8 %, 14·9 % and 16·5 %, respectively (P for the overall association = 0·036). Women living in severely food-insecure households had an increased prevalence of EW compared with their food-secure counterparts (PR = 1·96; 95 % CI 1·18, 3·27; P = 0·007), after adjusting for important confounders.

The study suggests that severe but not mild or moderate HFI is independently associated with EW among adolescents residing in Brazil, a middle-income country undergoing the nutrition transition.