Public health researchers cheered an encouraging trend recently: Childhood obesity rates, which rose steadily through the 1980s and 1990s, seemed to have plateaued in the 2000s.
But new research suggests a different, troubling problem lurking behind that plateau — a steep rise in the rates of severe obesity, particularly among older and minority children.
The fraction of adolescents with severe obesity — a body mass index of 40 or greater — has more than doubled from 0.9 percent in 1999 to 2.4 percent in 2013 and 2014.
According to William Dietz, an expert on obesity and director of the Sumner M. Redstone Global Center for Prevention and Wellness at George Washington University, the data included in the report suggests that over 6 million children and adolescents could suffer from severe obesity.
"The prevalence of obesity has remained constant, but severe obesity is increasing," said Dietz. "Kids who already have obesity seem to be getting more severe."
Since 2004, the number of children that have BMIs of 30 or greater has hovered around 17 percent, experiencing marginal change from year to year. But what has changed dramatically since 2004 (and even before) is the percentage of children with extremely high BMIs.
Without intervention obesity typically worsens, and contributing factors can be psychological
Kids who develop obesity at an early age are more at risk of developing severe obesity over time, gaining weight as they grown into teenagers, study co-author Asheley Skinner says.
For example, if a child has a BMI over 30 when he or she is five, chances are that without medical intervention, the child's BMI levels will surpass 35 or 40 as he or she enters adolescence.
"Kids with more severe forms of obesity are first developing obesity at younger ages and it gets worse and worse over time," said Skinner. "We live in a world where kids aren’t as active and it's easy for obesity to get continuously worse."
Additionally, once a child or teenager has severe obesity, it's a much more challenging disease to treat because of factors ranging from cardiovascular and metabolic complications to underlying psychological issues. As Dietz told me, adverse childhood experiences like sexual violence, verbal abuse, divorce, hunger, and homelessness can all contribute to a child's obesity.
"A significant proportion — about 20 percent of severe obesity in adults — is the result of adverse childhood experiences," said Dietz. "And my guess is it’s even greater."
Both Hispanic and black children have higher rates of prevalence for more severe forms of obesity than their white counterparts.
In 2013 to 2014, 3.5 percent of black children included in the study were found to have BMIs greater than 40. This was nearly a whole percentage point higher than any other race or ethnicity examined in the study. Additionally, 8.6 percent of Hispanic children had a BMI greater than 35, and in total, 41.8 percent of Hispanic children in the study were classified as overweight.
Dietz said there are significant ethnic differences in the prevalence of obesity. In adult women, the highest rates of obesity are among African-American women, meaning many of the racial and ethnic disparities in childhood obesity carry on into adulthood.
Health care practitioners don't have the resources to treat obesity properly
Data from the Agency for Healthcare Research and Quality indicates that health care practitioners are inadequately prepared to treat patients with severe obesity. The agency estimates there are approximately 125,000 primary care pediatricians and family practitioners in the US, which means the average primary care practice may treat up to 50 pediatric patients with severe obesity.
Skinner says this places an undue burden on primary care physicians, as on average a child suffering from severe obesity needs at least 26 hours of intervention. A primary care provider will not be able to have that much contact with a patient. "You're going to need a clinical intervention," says Skinner. "Or a specialty weight loss clinic or intervention in the community that is particular to a child."
As Dietz laments, "We lack a standard of care for children and teenagers with obesity. It’s a big problem and there is not an immediate solution."