First Lady Michelle Obama exercises with staff, parents and children at… (Gerald Herbert / Associated…)
Obesity among low-income preschool-age children has declined slightly in many states, including California, providing some evidence that the battle against childhood obesity may finally be turning, according to researchers at the U.S. Centers for Disease Control and Prevention.
The percentage of obese children among low-income 2- to 4-year-olds from California dropped from 17.3% to 16.8% between 2008 and 2011, and declined in 18 other U.S. states or territories. Obesity prevalence increased in only three states, according to a study summarizing the findings. There was no significant change in obesity rates in the remaining 21 states and territories for which scientists had reliable data.
"We've seen isolated reports in the past that have had encouraging trends, but this is the first report to show many states with declining rates of obesity in our youngest children after literally decades of rising rates," the CDC's director, Tom Frieden, said during a phone call with reporters Tuesday.
"But the fight is far from over," he added.
About 1 in 8 preschool-age children in the U.S. are considered obese, the report noted. The obesity epidemic hits African American and Latino children hardest; both groups have prevalence rates higher than the national average.
The CDC study included approximately 11.6 million preschoolers, including a large number of participants in the U.S. Department of Agriculture's Special Supplemental Nutrition Program for Women, Infants and Children. WIC, as it is known, provides states with grant money for supplemental food and nutrition education for low-income children under the age of 5.
Children in the study had their body mass index calculated twice a year over the course of four years. The research team controlled for differences in sex, ethnicity and age when analyzing changes in obesity prevalence over time.
In the 19 states and territories that saw declines, obesity prevalence decreased 0.3 to 2.6 percentage points, with the greatest drop occurring in the U.S. Virgin Islands. Such declines "are small but statistically significant," Frieden said.
They also represent what may be a general shift. In 1990, when the CDC began collecting comprehensive data, overall national obesity rates among preschoolers stood about 10%. That figure rose consistently until peaking in 2007 at 14.9%, and dropped to 14.4% by 2011.
Though the study authors did not attribute the declines to any specific factor, they suggested that national initiatives aimed at reducing childhood obesity, such as First Lady Michelle Obama's "Let's Move!" campaign, could have played a role.
Michael Goran, director of USC's Childhood Obesity Research Center, called the study "an impressive set of data" based on "a very large sample." He commended the researchers' focus on disadvantaged preschoolers.
"I think the biggest problem with obesity right now is in low-income people, and this is where the action needs to be," he said.
But Goran also said that the declines observed in the study were small, and that the research included only people considered "obese" and not those considered merely "overweight," who are also at increased risk for health problems.
He said he would have also liked to see the results broken down by ethnicity, especially for states like California with large groups of vulnerable populations, such as Latinos. (Texas, notably, was not included in the study.)
"I don't have a lot of optimism that we've turned a corner," Goran said.
Though California has no publicly funded statewide obesity-reduction initiative directed specifically at preschoolers, there are local efforts to expand access to open spaces and healthy diets.
First 5 LA, a nonprofit focusing on children 5 and under, has invested nearly $10 million on 37 parks and recreational areas across Los Angeles County, where 21% of 3-year-olds and 22% of 4-year-olds receiving support from WIC are overweight or obese, according to 2011 data.