Richard S. Strauss, of the UM-DNJ-Robert Wood Johnson School of Medicine, New Brunswick, New Jersey, and Harold A. Pollack, of the University of Michigan, Ann Arbor, investigated recent changes in the prevalence of overweight children within a nationally representative sample.
The sample was from the National Longitudinal Survey of Youth, a prospective cohort study conducted from 1986 to 1998, among 8270 children aged 4 to 12 years.
Being overweight was defined as body mass index (BMI) greater than the 95th percentile for age and sex.
The percentage of children with BMIs above the 85th percentile for age and sex were also analyzed to assess the total proportion of children who are considered overweight and at risk for being overweight.
The roles of race/ethnicity, sex, income, and region of residence were also examined.
The researchers found that between 1986 and 1998, the prevalence of overweight children increased significantly and steadily.
By 1998, the prevalence had more than doubled among African-Americans and Hispanics, and had increased by over 50% among whites.
Among African-American and Hispanic children, 21.5% and 21.8%, respectively, were overweight (compared with approximately 10% prevalence of overweight in both groups in 1986).
It was found that 12.3% of white children were overweight (compared with approximately 8% in 1986).
The relative weight of overweight children also increased from 1986 to 1998, suggesting that the severity, as well as the prevalence, increased over the period.
| Both prevalence and severity of overweight children has increased.
| Journal of the American Medical Association |
After adjusting for confounding variables, prevalence increased fastest among minorities and southerners, creating large demographic differences in the prevalence of childhood obesity by 1998.
"Like many other preventable adverse health states, childhood obesity reflects the convergence of many biological, economic, and social factors," the authors write.
"Obesity arises from multiple causes, some as intimate as the family dinner table, others as seductive as television or the latest children's video game. Provision of high-fat meals and snacks in school settings is both a powerful temptation and a clear signal of accepted nutritional norms."
"Innovative strategies have been evaluated to address each of these concerns," they continue.
"No one intervention, by itself, is likely to produce large reductions in the prevalence of obese or overweight children. Like adolescent smoking, teen pregnancy, and youth violence, childhood obesity is prevalent because it arises from deeply rooted behaviors and from social practices that are hardly confined to children.
"Given the profound consequences of childhood inactivity, poor nutrition, and obesity throughout the lifespan, urgency is warranted in responding to this epidemic."