Public health initiatives have failed to curtail the rise in childhood obesity, with rates increasing in all age groups over the last several years, a new study shows.
“Despite intense clinical and public health focus on obesity and weight-related behaviors in the past decade, obesity prevalence remains very high, with scant evidence these efforts are counteracting the personal and environmental forces contributing to excess weight gain in children — at least on a national scope,” authors wrote in the study “Prevalence of Obesity and Severe Obesity in US children, 1999-2016” (Skinner AC, et al. Pediatrics.Feb. 26, 2018, https://doi.org/10.1542/peds.2017-3459).
Several recent studies have indicated that obesity rates are leveling off among all age groups and are decreasing among children ages 2-5 years. Other research, however, shows rates of severe obesity are rising sharply among adolescents and non-Hispanic black children.
The authors of this study used data from the 1999-2016 National Health and Nutrition Examination Surveys (NHANES) to detail the most recent obesity rates in children and adolescents ages 2-19 years as well as long-term trends. NHANES participants undergo a physical exam during which their height and weight are measured. These measurements were used to calculate body mass index (BMI).
Researchers defined overweight as ≥ 85th percentile for age- and sex-specific BMI. Obesity was broken into three classes:
- class I: BMI ≥ 95th percentile for age and sex;
- class II: BMI ≥ 120% of the 95th percentile for age and sex or BMI of 35 or greater, whichever is lower; and
- class III: BMI ≥ 140% of the 95th percentile for age and sex or BMI of 40 or greater, whichever is lower.
The 2015-’16 NHANES showed the prevalence of overweight and all classes of obesity were highest in Hispanic and black children (46% and 38%, respectively). Asian children had lower rates of overweight and all classes of obesity (23%).
Rates of overweight and obesity also increased with age. Nearly 42% of adolescents ages 16-19 years had overweight or obesity, with 4.5% in class III.
When comparing the 2015-’16 and 2013-’14 surveys, the only significant changes were among preschoolers and adolescent females. The rate of class I obesity increased from 9% to 14% among children ages 2-5 years, and overweight among females ages 16-19 rose from 36% to 48%.
Data from 1999-2000 to 2015-’16 showed a positive linear trend for overweight and all classes of obesity for both sexes with all ages combined, and the change was greatest among Hispanic females.
“Despite reports that obesity in children and adolescents in the United States has stabilized in recent years, our more nuanced view highlights the continued upward trend for this nationally representative sample,” authors wrote.
In a related commentary, David S. Ludwig, M.D., Ph.D., of the New Balance Foundation Obesity Prevention Center at Boston Children’s Hospital, acknowledged that the public health approach to fighting obesity has failed. He called for a comprehensive national strategy to “prevent a looming public health disaster.”
“The battle against childhood obesity faces many obstacles, most notably entrenched special interests and a ‘business as usual’ mindset,” Dr. Ludwig said. “But with political will and collaboration across key sectors of society, we can hopefully, soon, begin to end this worsening epidemic.”