Recent reports suggest that the rapid growth in youth obesity seen in the 1980s and 1990s has plateaued. We examine changes in obesity among US adolescents aged 12-17 y by socioeconomic background using data from two nationally representative health surveys, the 1988-2010 National Health and Nutrition Examination Surveys and the 2003-2011 National Survey of Children's Health. Although the overall obesity prevalence stabilized, this trend masks a growing socioeconomic gradient: The prevalence of obesity among high-socioeconomic status adolescents has decreased in recent years, whereas the prevalence of obesity among their low-socioeconomic status peers has continued to increase. Additional analyses suggest that socioeconomic differences in the levels of physical activity, as well as differences in calorie intake, may have contributed to the growing obesity gradient.
Frederick, Carl B., Kaisa Snellman, and Robert D. Putnam. "Increasing Socioeconomic Disparities in Adolescent Obesity." Proceedings of the National Academy of Sciences 111.4 (January 2014): 1338-1342.