A new study from the Keck School of Medicine of USC reveals that air pollution exposure during childhood may set off a chain reaction leading to insulin resistance in young adulthood—and minority communities may be especially vulnerable. Researchers found that changes in body mass index (BMI) during adolescence explain nearly half of the link between early exposure to traffic-related air pollution and insulin resistance, a precursor to type 2 diabetes.
“We estimated about 42% of the relationship between early pollution exposure and insulin resistance can be explained by accelerated BMI growth trajectories,” said Fangqi Guo, PhD, MPH, lead author and postdoctoral scholar at USC. These findings remained significant even after adjusting for smoking, race/ethnicity, socioeconomic status, and family history of diabetes.
The study focused on nitrogen oxides from vehicle emissions, a major component of traffic-related air pollution. Children exposed to these pollutants who also experienced rapid weight gain were more likely to show signs of insulin resistance in their 20s.
Guo emphasized the implications for families living in high-traffic urban areas, who may already face other health and socioeconomic challenges. “Our discovery is especially important for families and children living in high-traffic urban areas who may already face other socioeconomic or health disparities,” she said.
The researchers call for early interventions that promote healthy weight and reduce environmental exposures. “Public health efforts that address both environmental exposures and childhood obesity could make a significant impact,” Guo added.
See “Changes in BMI during adolescence may explain link between air pollution exposure and insulin resistance, study shows” (May 20, 2025)
