Aug. 16, 2010 -- Obesity rates among children appear to be dropping for some groups, but not for all, new research suggests.
An analysis including more than 8 million California children and teens showed encouraging declines in obesity following a peak in 2005 among Asian and white boys and girls and among Hispanic boys.
But obesity continued to climb among African-American and American Indian girls and remained stable for Hispanic girls.
And public health efforts aimed at addressing the obesity epidemic do not appear to have had much impact for the heaviest children -- those with body mass indexes (BMIs) in the 99th percentile.
The findings can be viewed as both an encouraging and troubling report card on these efforts, researcher Kristine Madsen, MD, MPH, of the University of California, San Francisco, tells WebMD.
Published online today, the study appears in the September issue of the journal Pediatrics.
“On the one hand it is really heartening to see the declines in white and Asian children and the plateau in Latino youth,” she says. “But this is tempered by concerns about increasing racial disparities in childhood obesity. The fact that the gap appears to be widening is very troubling.”
School Soda Ban Preceded BMI Declines
The study examined body fat levels as measured by BMI among California public school children between 2001 and 2008.
California is one of the few states that require school-based BMI assessment, which is conducted in the fifth, seventh, and ninth grades.
For most groups, obesity rates peaked around 2005 -- the same year that California lawmakers banned the sale of sugary soft drinks and snacks in schools and took other actions to address childhood obesity.
Madsen says it is probably no coincidence that obesity rates began to plateau around this time and have since declined for some.
In 2008, about 20% of 8- to 17-year-old public school children in California were obese and 3.6% were severely obese, meaning they had BMIs in the 99th percentile.
American Indian children and teens had later peaks and larger increases in obesity prevalence after 2001 than any other group.
Racial disparities were greatest for the heaviest children and teens. In 2008, close to 5% of American Indian girls and 4.6% of black girls were severely obese, compared to just over 1% of white girls.
‘Efforts Not Reaching Most Vulnerable’
The analysis was limited to California schoolchildren, but the researchers point out that about one in eight children in the U.S. live in the state.
“I don’t think this is limited to the West Coast,” Madsen says. “We are certainly seeing similar trends in the larger, more diverse states like Texas and New York.”
While the findings suggest that efforts to reduce childhood obesity are having an impact, they also suggest that these efforts are not reaching the most vulnerable kids, such as those from low-income families.
Schools that serve predominantly poor students typically have the least resources to devote to public health initiatives like those that target obesity.
Madsen says doing away with this inequity would represent a major step in addressing the disparity in childhood obesity.
Pediatrician Sandra Hassink, MD, who directs the Nemours Obesity Initiative at A.I. Dupont Hospital for Children in Wilmington, Del., says efforts to raise awareness about childhood obesity and address the issue have had an impact.
Hassink chairs the American Academy of Pediatricians’ Obesity Leadership Workgroup.
"We continue to see opportunities for physical activity and choosing healthy foods expand for some, but not for all, children,” she tells WebMD. “We may be missing barriers that might keep these interventions from being accessible to all.”
She adds that efforts to address childhood obesity must begin at home with parents and caregivers. She suggests:
- Limiting the availability of sugary drinks and energy dense, nutritionally lacking snack foods within the home
- Cooking healthy meals at home more often and eating out less often
- Eating evening meals together whenever possible
- Keeping televisions out of children’s bedrooms
“Families need to take stock and assess their own health behaviors,” she says. “After this the next logical step is to ask schools or community groups what they are doing.”