In recent years, the rise in obesity rates has become a global public health concern. While various factors such as diet and physical activity levels have been linked to obesity, a new study has shed light on another potential contributor – environmental exposures during pregnancy. The study suggests that exposure to certain chemicals and pollutants during pregnancy can increase obesity risk differently in boys and girls. These findings could have significant implications for public health policies and strategies aimed at reducing the prevalence of obesity.
A recent study published in BMC Medicine highlights the difference in risk for obesity and neurodevelopmental delay between boys and girls depending on certain types of prenatal exposure. The study found a combination of four exposure levels that protect girls from developing these complications.
Studies have previously observed developmental differences between boys and girls in many biological processes, resulting in varying susceptibility to infection, neurological development, and the pathogenesis of common diseases, notably obesity. A higher prevalence of obesity in boys than girls was uncovered in 96% of high-income countries globally.
However, studies analyzing the effects of environmental factors on biological processes primarily focus on sex as a confounding factor rather than a causative factor. Therefore, the scientists developed a method of casual modeling to determine the profiles of certain prenatal exposures that may protect girls more than boys from obesity and neurodevelopmental delay.
The scientists analyzed the data of 1044 children collected from the Human Early Life Exposome (HELIX) study conducted in Europe. Specifically, they analyzed clinical, neuropsychological, and methylation data during childhood (5 – 11 years) that were related to 93 prenatal exposures.
After applying an exposome-wide interaction analysis, the scientific team identified a combination of prenatal environmental factors. The combination of exposures creates specific environments where one sex is more susceptible to developing obesity than the other. The four identified prenatal exposures were moderate dairy consumption, non-smokers’ cotinine levels, low abundance of rich facilities, and the presence of green spaces. These four exposures were used to develop a multi-exposure profile, which was further used to classify the entire study population.
About 64% of the children were classified into the prenatal environment category E1, characterized by moderate dairy consumption, non-smokers’ cotinine levels, low abundance of rich facilities, and the presence of green spaces. The remainder of the children were classified into the E0 environment, which combined the remaining exposure levels.
The study revealed that girls born to mothers who had moderate dairy consumption, non-smokers’ cotinine levels in the blood, low abundance of rich facilities, and green space exposure during pregnancy had a significantly lower risk of developing childhood obesity and neurodevelopmental delay than boys. This demonstrates the impact of prenatal environmental factors on sex differences in developmental biology and the pathogenesis of diseases.
Epigenome-wide association studies were conducted using DNA methylation data. The analysis identified several biological processes linked to neurodevelopment, including synapse reorganization and the structural and functional regulation of synapses. This study’s findings suggest the requirement for future research that considers sex as a potential causative factor in prenatal environmental effects on developmental biology and pathogenesis.
In conclusion, this study sheds light on the complex relationship between environmental exposures during pregnancy and future obesity risks in children. The findings suggest that these exposures affect boys and girls differently, with girls being more vulnerable to certain types of environmental factors. Identifying these risk factors is vital to developing targeted interventions aimed at reducing obesity rates and improving overall health outcomes for children. This study underscores the importance of continued research in this area to help protect the health of generations to come.
