Body Mass Index of Children Highest in Midwest, May Be Linked to Regional Factors

Children in the United States 15 years of age or younger living in the Midwest have the highest body mass index (BMI) levels on average, whereas those in the Western United States have the lowest, according to a study published in Obesity. The investigators said the results of the study suggest regional differences may play a role in the development of childhood obesity.

"If we know the factors that affect children's body size, we can help prevent them from becoming overweight or obese," said the study's senior author Dana Dabelea, MD, PhD, professor of pediatrics and epidemiology at the Colorado School of Public Health and director of the LEAD Center, in a press release. "This study looked at factors related to children's body size, like where children live, how much they weighed at birth, and their ethnic background."

The study also found that a higher birthweight and lower levels of formal education among mothers was associated with a higher BMI in children. Further, Black and Hispanic children had a higher BMI than non-Hispanic white children in some parts of the United States, but not all.

To conduct the research, investigators drew their study population from the Environmental influences on Child Health Outcomes Program, which investigates the effects of environmental exposures on the health of children. More than 14,000 children were enrolled in the study, with the investigators studying their height and weight between the years 2000 and 2018, calculating BMI based on these data.

According to the investigators, children in the Midwest had the highest average BMI, followed by the Northeast, the South, and the West. This connection between geographical regions and BMI is not well understood, according to the study, especially when studying the BMI of children.

Although adult data show diet quality and time doing moderate-to-vigorous exercise are higher in the West and Northeast compared to the South and Midwest, other studies have shown no regional variation in physical activity, according to the authors of the current study. Further, environmental factors such as density of fast food restaurants, supermarkets, and recreation facilities have been linked to childhood BMI, according to the investigators, but there is currently little evidence of regional variation. The study authors hope that their findings will lead to additional research further investigating why BMI varies by region.

"For example, researchers could study whether children's eating habits and their physical activity levels also vary based on the area they live in," Bekelman said in the release. "Another next step is to find out why there are racial and ethnic differences in BMI in some areas but not others."

REFERENCE

Study finds body mass index for children greatest in Midwest, least in West [news release]. Science Daily; September 1, 2021. Accessed September 7, 2021. https://www.sciencedaily.com/releases/2021/09/210901142710.htm