The last year or so has given the nation mixed pictures on childhood obesity, with plenty of challenges ahead. For kids aged 12 to 19 years, the level of obesity has continued its steady march upward, according the National Health and Nutrition Examination Survey (NHANES) released in mid-2016.
Back in the 1966-1970 period, 4.6% of children that age were obese. By 2011-2012, the number had more than quadrupled to 20.5%. The latest numbers for 2013-2014 show a slower increase, nudging up to 20.6%.
For children aged 6 to 11 years, the picture is not as bad, with obesity peaking at 19.6% in 2007-2008 and falling to 17.4% in 2013-2014.
For kids aged 2 to 5 years, it’s been more up and down, peaking at 13.9% in 2003-2004, then falling and rising through several cycles until it was at 8.4% in 2011-2012, the lowest since 1988-1994. However, it rose again to 9.4% in the 2013-2014 cycle.
On the other hand, new numbers for the very smallest children participating in the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) are particularly good news, says William Dietz, MD, PhD, professor of prevention and wellness at George Washington University, Washington, DC. For children aged 3 months to 23 months, the prevalence of high weight for length had risen from 13.4% in 2000 to 14.5% in both 2004 and 2010; however, in 2014 it took a remarkable fall down to 12.3%.
The study, done by the Centers for Disease Control and Prevention (CDC) and the US Department of Agriculture, was published in the January 2017 Pediatrics.
It’s important that the percentage of high weight for most minority groups fell particularly steeply, says Dietz, who previously headed the Division of Nutrition, Physical Activity, and Obesity at the CDC and was involved in a previous version of this survey. He points out that half of US children participate in WIC in the first year of life, and this survey captures about a million or more kids a year. He also notes the drop may have been in part because of changes in the WIC food package.
More obesity prevention is needed
In addition, a recent report in the CDC’s Morbidity and Mortality Weekly Report says the obesity rate was at 14.5% for children aged 2 to 4 years in the WIC program in 2014, down from 15.9% in 2010. The CDC report calls for continued obesity prevention initiatives at the national, state and local levels.
“I think we are doing a lot of great things with this focus on public health and the media on childhood obesity as a major concern,” says Peter Katzmarzyk, PhD, professor in pediatric obesity and diabetes at Pennington Biomedical Research Center at Louisiana State University, Baton Rouge. However, he does point out obesity is going up in most countries, and “worldwide we really don’t know how to handle this problem. So we are still working on it.”
A call to standardize data collection
A 2016 report from the National Academies of Sciences, Engineering, and Medicine (NASEM) notes that although data on obesity prevalence and trends come from many different sources, the NHANES is “currently the only ongoing nationally representative population survey that directly measures participants’ heights and weights.”
However, the NHANES, despite its strengths, is not designed to show variations across states and other geographical regions, notes the NASEM report, Assessing Prevalence and Trends in Obesity: Navigating the Evidence.
A number of current data sources offer “specific and distinct information about the state of obesity,” but they have various characteristics and are limited in their comparability, notes the NASEM report. It recommends that leaders from the obesity field be convened to standardize data collection and reporting for the national, state, and local levels.
Experts say keep the discussion going
Meantime, a recently released summary of a 2015 NASEM workshop lays out some of the current discussion about childhood obesity.
For example, Julie Mennella, PhD, a member at the Monell Chemical Senses Center in Philadelphia, Pennsylvania, told the session that dietary patterns, such as eating fruits and vegetables, are set before age 2 years. On the other hand, there are opportune moments, including a birth of a child, when people can be motivated to change eating habits.
Early care and education settings are missed opportunities for obesity prevention, and structured physical activity in those settings increases children’s overall physical activity, said Dianne Ward, EdD, professor of nutrition at the University of North Carolina Gillings School of Global Public Health, Chapel Hill.
Most basically, Katzmarzyk says, he would tell pediatricians not to ignore the problem. Often he hears pediatricians are hesitant to talk to parents about obesity, perhaps for fear they might not bring their child back. He suggests that if the doctors are not comfortable giving their own advice, they can refer the child to a specialist or a program. He also stresses the need to tackle the problem on multiple fronts, including with the physician, the schools, and the home environment.