Trends and Correlates of Overweight and Obesity Among Adolescents from 2002 to 2010: A Three-Cohort Study Based on a Representative Sample of Portuguese Adolescents

ObjectiveTo report the prevalence and factors associated with overweight/obesity in a representative sample of Portuguese adolescents, from three different cohorts. MethodsData on 8,610 adolescents aged 11-17, who participated in the 2002, 2006, and 2010 Health Behaviour in School-aged Children survey (HBSC/WHO) were analyzed. Body mass index (BMI) was calculated based on self-reported weight/height. Factors investigated as potential correlates of overweight/obesity were as follows: physical activity, screen time, life satisfaction, and perception of health. ResultsThe prevalence of overweight/obesity was around 20% for boys and 17% for girls between 2002 and 2010. Among boys, the prevalence of overweight/obesity was negatively associated with age in 2002 (odds ratio, OR=0.89, P<0.01), 2006 (OR=0.92, P<0.05), and 2010 (OR=0.91, P<0.05). Those who engaged in physical activity were less likely to be classified as overweight/obese in 2006 (OR=0.89, P<0.01) and 2010 (OR=0.92, P<0.05). Among girls, as age increased, the likelihood of being overweight/obese significantly decreased in all years. Results from 2002 (OR=0.69, P<0.001) and 2010 (OR=0.88, P<0.01) varied by almost 20%. ConclusionThe prevalence of overweight/obesity is still high, but seems to have stabilized. Physical activity, for boys, and perception of health, for girls, are factors associated with a lower likelihood of being overweight or obese. Am. J. Hum. Biol. 26:844-849, 2014. (c) 2014 Wiley Periodicals, Inc.