Kids who are overweight or obese often struggle with schoolwork, and now new research provides clues on how excess weight may harm the developing brain.
“The main takeaway is to raise awareness about brain health consequences of obesity besides physical health consequences, especially since obesity rates are very high and continue to rise,” says study author Simone Kaltenhauser, a post-graduate research fellow in radiology and biomedical imaging at the Yale School of Medicine in New Haven, Conn.
About one in every five American kids is now obese, according to the U.S. Centers for Disease Control and Prevention.
What the study shows
For the study, researchers looked at several types of brain scans in more than 5,100 kids aged 9 to 10 who took part in the ongoing Adolescent Brain Cognitive Development (ABCD) study. Of these, 21% were overweight and 17.6% were obese.
What did they find? There were structural and functional brain impairments in kids who were overweight or obese when compared to kids who weren’t, and these changes could contribute to poor academic performance.
Specifically, kids who were overweight or obese showed a thinning of the outermost layer of their brain (the cortex), and this has been linked with impaired executive functioning skills, such as planning and juggling multiple tasks. What’s more, the integrity of the brain’s white matter was impaired in the corpus callosum (which connects the brain’s two hemispheres) and in the pathways within the brain’s hemispheres that connect the lobes of the brain in kids who are overweight or obese.
In addition, brain networks involved in reward-based decision-making and control of behaviors showed reduced connectivity in kids who are overweight or obese.
These patterns persisted over two years, the study showed.
“Our findings provide an important potential explanation of other studies that show higher body mass index [BMI] in children is associated with poor cognitive functioning and academic achievement,” Kaltenhauser says. (BMI is a measure of body fat that takes height and weight into account.)
RELATED: Words Can Wound: Tips For Talking to Kids About Obesity
Can weight loss help?
It’s too early to say whether weight loss and increased physical activity can offset some of these brain changes, but it is possible, she noted.
“Brain plasticity, or the ability to reorganize neural pathways of children, is very high, and there is evidence in the literature that