Early-Life Environmental Exposures and Childhood Obesity: An Exposome-Wide Approach

Area of Science:

• Environmental health science
• Pediatric epidemiology
• Obesity research

Background:

• Environmental exposures are increasingly implicated in childhood obesity development.
• Previous studies often focused on single exposure groups, limiting comprehensive understanding.
• Early life is a critical window for environmental influences on adiposity.

Purpose of the Study:

• To systematically assess associations between a wide range of early-life environmental exposures and childhood obesity.
• To utilize an exposome-wide approach for a comprehensive analysis.
• To identify key environmental factors contributing to childhood obesity risk.

Main Methods:

• The Human Early Life Exposome (HELIX) study involved 1,301 children aged 6-11 years across six European cohorts.
• Measured 77 prenatal and 96 childhood exposures, including air pollutants, built environment, and chemical biomarkers.
• Employed an exposure-wide association study (ExWAS) and deletion-substitution-addition (DSA) algorithm for multiexposure modeling.

Main Results:

• Maternal smoking was linked to higher child Body Mass Index (BMI).
• Childhood exposures associated with increased BMI included indoor air pollution (particulate matter, nitrogen dioxide), secondhand smoke, and less favorable built environments.
• Specific chemical biomarkers showed varied associations with BMI, with some metals linked to higher BMI and others to lower BMI.

Conclusions:

• This study provides comprehensive evidence linking smoking, air pollution, and built environment characteristics to childhood obesity.
• The findings emphasize the importance of considering multiple environmental exposures in early life.
• Acknowledges potential reverse causality bias in cross-sectional biomarker analyses.