Obesity Prevention During Preadolescence and Adolescence

Abstract

Pediatric obesity is a serious public health problem in the United States. According to the 2003–2004 National Health and Nutrition Examination Survey (NHANES), approximately 37% of children and 34% adolescents are overweight or at risk for overweight (i.e., body mass index (BMI) national 85th percentile for age and sex) (see Chapter 3) (Ogden et al., 2006). The prevalence of overweight is particularly high among African Americans and Hispanics. However, these estimates may underestimate the true prevalence among preadolescents and adolescents due to relying on the pediatric BMI standards from the Centers for Disease Control and Prevention (CDC) (Centers for Disease Control (CDC),2002). The CDC suggests that children and adolescents at or above the 95th percentile of BMI for age and gender be classified as overweight, but at age 13.5 years for boys and age 12 for girls, some children with a BMI greater than 25 kg/m2, the adult cut-off for overweight, will not be classified as overweight since that is below the 95th age and gender-specific percentile for BMI (see Chapter 2). This problem is much less of an issue when a BMI 85th percentile for age and gender is used to define overweight in youth. In that case, the inconsistent classification does not occur until 17.5 years for the boys and 17 years for girls. Thus the reported prevalence of obesity among adolescents in the United States likely underestimates the true prevalence (Gordon-Larsen, Adair, Nelson, & Popkin, 2004). As discussed in Chapters 18 and 19, obesity prevention in children and youth can be a focus prior to preadolescence and adolescence, but this maturational transition period may be particularly important in the prevention of overweight and obesity. The prevalence of adolescent overweight has increased almost three-fold since the late 1980s (Ogden et al., 2006; Ogden, Flegal, Carroll, & Johnson, 2002), suggesting an urgent need to identify and address the causes of this relatively recent, population-wide phenomenon. Weight status during preadolescence and adolescence is a good predictor of adult weight status. For example, Whitaker et al. (Whitaker, Wright, Pepe, Seidel, & Dietz, 1997) observed that the odds of being an obese adult were 28 times higher for an obese 10–14 year old child compared to a non-obese child of the same age. Moreover, obese children are not the only ones who become Chapter 20