Childhood obesity, after multiple studies into its genetic and environmental factors, has since outgrown the image of a “lifestyle” disease. Traffic pollution, urban-rural difference, and family dynamics have been few of the many subjects individually studied to have associated health risks.
However, USC and the Barcelona Institute for Global Health (ISGlobal) released one of the first studies to comprehensively profile multiple environmental factors linked to childhood obesity.
Studying exposure factors in context with one another
“People are not exposed to only one chemical during their lives,” said Dr. Lida Chatzi, Associate Professor of Preventive Medicine at the Keck School of Medicine of USC. “With that in mind, we try to understand the totality of environmental exposures.”
The main risk factors? Smoking during pregnancy and air pollution. In combination with a person’s built habitat, air pollution correlates with the highest childhood obesity rates and body mass index.
In comparison to previous analyses, the study manages to look at air pollution in context to other environmental variances. For example, they spend a portion of the study looking at specific socioeconomic factors and urban development. High BMI correlates with densely populated areas. But, BMI was lower in areas with more concentrated resources: businesses, community services, educational institutions, restaurants, shopping, and more.

Introducing the exposome
USC and ISGlobal gathered data on women and their children starting at pregnancy, through a collaborative longitudinal research project known as the Human Early Life Exposome (HELIX) study. The researchers studied a group of about 1,300 children aged 6 to 11 years across 6 European countries: France, Greece, Lithuania, Norway, Spain, and the United Kingdom.
The study hinges on what the scientists call the “exposome,” a comprehensive characterization of exposure risks on the genome. Dr. Martine Vrijheid, a research professor at ISGlobal, hopes that in completing the exposome, they can illuminate prominent linkages between “the implications of public health … and modifying environmental exposure early in life.”
“This is one of the first studies that actually manages to measure so many different variables and so many factors of the environment and then tries to analyze them all together,” Vrijheid published in the peer-reviewed Environmental Health Perspectives.


Jessica is a writer based in NYC, with bylines at Vox and EGMNOW. You can pitch her stories at jessica [at] therising.co
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