May 8, 2010— -- Youngsters living in the southeastern United States are the most likely to be overweight or obese, while those from the far West are most likely to be thin, according to a new study that found considerable variability in children's weight by state and region.
In 2007, Mississippi had the highest prevalence of childhood obesity (21.9 percent), while Oregon had the lowest (9.6 percent), according to an online report in the May 3 Archives of Pediatrics and Adolescent Medicine.
Mississippi also had the highest proportion of children who were overweight (44.5 percent), while Utah had the lowest proportion (23.1 percent).
In general, children in the Southeast had higher prevalence of childhood obesity.
"Marked geographic disparities shown here indicate the potential for considerable reduction in childhood obesity," Gopal Singh of the U.S. Department of Health and Human Services and colleagues wrote.
"However, such disparities, if they continue to rise, would have profoundly adverse implications for any future efforts to reduce health inequalities among children and adults."
The prevalence of childhood obesity in the U.S. has more than tripled over the past three decades and remains high regardless of the age, sex, race and ethnicity, and socioeconomic standing.
Although research has found disparities by sex and race/ethnicity, fewer studies have examined the influence of geography on childhood obesity, because the sample sizes of the surveys routinely used are too small to produce state-specific estimates.
To overcome this hurdle, Singh and colleagues relied on data from the National Survey of Children's Health, a large sample that is designed to allow researchers to compare results among states.
The survey also offers data for both 2003 and 2007, allowing researchers to see how obesity and overweight prevalence changed between those years.
The researchers analyzed data from 50 states and the District of Columbia on 46,707 children in 2003 and 44,101 children in 2007. The children were between the ages of 10 and 17 years old.
They found that the prevalence of obesity increased by 10 percent for all U.S. children and by 18 percent for girls.
While the obesity rate declined by 32 percent for children in Oregon from 2003 to 2007, it increased by more than 40 percent in Arizona and Colorado.
Children living in Illinois, Tennessee, Kentucky, West Virginia, Georgia and Kansas had more than twice the adjusted odds of being obese than Oregon children.
Exploring the reasons for these disparities, the researchers determined that individual, household and neighborhood social and built environmental characteristics accounted for more than 40 percent of the state variance in childhood obesity and overweight, respectively.
The authors suggested that important environmental factors might include neighborhood crime, access to recreation facilities, outdoor parks and playgrounds, vehicular traffic congestion, fast food outlets and restaurants, and media promoting unhealthy food choices.
They suggested several policy initiatives that might reduce the prevalence of obesity and overweight:
The authors noted several limitations of the study, including the fact that the data they analyzed was based on parental reports of children's heights and weights, which may not have reflected the true prevalence of childhood obesity.
They also noted that response rates varied by state, which could have resulted in a bias in their state-to-state comparisons.