Exposure to smoke, pesticides, other factors linked to childhood obesity — study

Image: Ruslanshug/IStock.com via AFP Relaxnews

New research has identified some of the factors that could increase a child’s risk of being obese.

Led by researchers at the University of Southern California, United States, and the Barcelona Institute for Global Health (ISGlobal), Spain, the new study looked at data gathered from 1,301 children aged 6 to 11 years from six European countries — France, Greece, Lithuania, Norway, Spain and the United Kingdom — and from their mothers.

In contrast to previous studies, which have focused on just one or two environmental factors, the researchers used this data to look at the children’s exposure to 77 environmental factors during pregnancy and 96 during childhood, such as their exposure to air pollutants, tobacco smoke, chemical pollutants such as heavy metals and pesticides, and their access to green space.

“People are not exposed to only one chemical during their lives,” explained Dr. Lida Chatzi, senior author of the study. “They are exposed to multiple chemicals. With that in mind, we try to understand the totality of environmental exposures.”

The findings, published in the journal Environmental Health Perspectives, showed that smoking while pregnant was the factor with the strongest link to childhood obesity, and the only prenatal factor with a significant association. Exposure to smoking during childhood was also linked with having a higher body mass index (BMI), suggesting that quitting smoking is one way that both parents can help protect their child’s health.

“This is quite an important message,” Dr. Chatzi said. “Maternal smoking during pregnancy and exposures to secondhand smoke are quite prevalent worldwide.”

Exposure to air pollution, both in the home and outside, was another factor linked to a higher BMI, as were certain factors related to where the children lived. Children who lived in densely populated areas were more likely to have a higher BMI, but those who went to school in areas that have many facilities such as businesses, educational institutions, restaurants and shops — which suggests a higher level of walkability — were more likely to have a lower BMI.

“With more facilities, children can walk, ride their bikes, go play sports,” Dr. Chatzi said. “You can contrast this with what are described as food deserts, or areas with fewer facilities.”

The researchers point out that childhood obesity is a growing health problem across the world, which can increase children’s chances of developing many health problems later in life including type 2 diabetes, cancer, heart disease and mental health conditions.

“These findings provide further evidence that modifying environmental exposures early in life can limit the risk of obesity and associated complications,” said first author Martine Vrijheid. “The implications for public health are important since these results may help to identify obesity-related exposures that could be targeted for prevention and intervention early in life.” IB

RELATED STORIES:

Being obese could increase risk of dementia

Obesity in childhood linked to higher risk of anxiety, depression and early death—study