High Preteen BMI Linked to Changes in Brain Function and Structure

In a groundbreaking national study, researchers have discovered a significant association between obesity in preteens and their cognitive ability, brain structure and neural connections. The study, published in the International Journal of Obesity, compared overweight preteens with their counterparts who had a lower body-mass index (BMI) and found notable differences in their brains.

The research, which was funded by the National Science Foundation’s Harnessing the Data Revolution initiative, assessed approximately 5,000 children aged 9–10 across 21 sites in the United States. While the research only explores the relationship between BMI and brain measures and is unable to assign causation to the findings, the association has raised concerns among experts.

Raising an alarm

Dr. Caterina Stamoulis,  the study leader and director of the Computational Neuroscience Laboratory at Boston Children’s Hospital, emphasized the importance of monitoring brain health in adolescents with excess BMI. She pointed out that early adolescence is a critical period for brain development, and that frontal brain areas responsible for higher cognitive functions are particularly vulnerable to miswiring. “It raises an alarm that it’s important to track adolescents’ brain health, especially when they have excess BMI,” she added.

The study accrued subject data from the Adolescent Brain Cognitive Development (ABCD) study, a government-funded initiative that has gathered comprehensive behavioral and physiological data on various aspects of preteen health and development. Stamoulis and her team applied computational methods to process and analyze the data.

The findings showed that brain circuits responsible for higher-level cognitive functions, reward, emotion processing and attention were less efficiently organized, less well connected and less resilient in preteens with excess BMI. Further alterations were identified in the kids’ ability to problem-solve and utilize logic. These differences persisted even after accounting for factors such as sleep duration, screen time, physical activity, depression and weight-related self-worth, which could potentially impact both BMI and brain health.

Causation not established

Stamoulis highlighted that while the causative role of BMI in brain development is not established, interventions targeting mental health screenings, sleep quality, physical activity and screen time reduction could make a difference to preteens’ rapidly changing brains.

Future research will analyze two-year follow-up data from subsequent ABCD datasets to understand the long-term impact of excess BMI on brain development. Stamoulis also intends to examine both nutritional and genetic data from the ABCD study to gain further insights into the relationship between BMI and brain health. Once the brain is done wiring, it’s more difficult to intervene,” she said. “We want to see what neurodevelopmental trajectories these youth are on,” she concludes.

Reference: Brooks SJ, Smith C, Stamoulis C. Excess BMI in early adolescence adversely impacts maturating functional circuits supporting high-level cognition and their structural correlates. Int J Obes. 2023:1-16. doi:10.1038/s41366-023-01303-7

This article is a rework of a press release issued by Boston Children’s Hospital. Material has been edited for length and content.