title: Trends of underweight, overweight, and obesity in Brazilian children and adolescents.
abstract: OBJECTIVE
  To describe and analyze the trends of occurrence of underweight, overweight, and obesity in schoolchildren.
  
  
  METHODS
  This was a longitudinal study of trends conducted in a voluntary sample of Brazilian children and adolescents. The sample was grouped by year of collection (period I: 2005 and 2006; period II: 2007 and 2008, and period III: 2009-2011), age category (children: 7 to 10 years, and adolescents: 11 to 14 years), and stratified by gender. The body mass index was used to classify the nutritional profile. Trend analysis was verified using multinomial logistic regression (p<0.05).
  
  
  RESULTS
  Mean occurrences were 2.11% for underweight, 22.27% for overweight, and 6.8% for obesity. There was a decrease of underweight in male adolescents from period I to II, as well as an increase in female children from period II to III. Regarding overweight, there was an increase followed by a decrease in male children. Regarding obesity, there was an increase from period I to II in all age groups and for both genders.
  
  
  CONCLUSIONS
  The prevalence of underweight was less than 5% in all categories of age and gender. However, the categories of overweight and obesity showed higher values, and together comprised almost 30% of the young Brazilian population; moreover, a trend toward increase in prevalence of obesity was observed up to the year 2008, followed by the maintenance of these high prevalence rates.
authors.affiliation: Master's Degree in Human Movement Sciences, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS, Brazil. Electronic address: larissasabbado@yahoo.com.br.
authors.forename: Larissa S
authors.initials: LS
authors.lastname: Flores
authors.forename: Anelise R
authors.initials: AR
authors.lastname: Gaya
authors.forename: Ricardo D S
authors.initials: RD
authors.lastname: Petersen
authors.forename: Adroaldo
authors.initials: A
authors.lastname: Gaya
mesh_terms: D000293:Adolescent; D015992:Body Mass Index; D001938:Brazil / Q000453:epidemiology; D002648:Child; D005260:Female; D005544:Forecasting; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D009752:Nutritional Status; D009765:Obesity / Q000453:epidemiology; D050177:Overweight / Q000453:epidemiology*; D015995:Prevalence; D013851:Thinness / Q000453:epidemiology*; D013997:Time Factors
keywords: BMI; Children and adolescents; Crianças e adolescentes; Desnutrição; IMC; Malnutrition; Obesidade; Obesity; Overweight; Sobrepeso