Published in Environmental Health, the study finds that exposure to air pollution during pregnancy may increase a child’s risk of being overweight. Though more research is needed, initial results show that those babies gain weight more quickly during their first year of life, potentially leading to health concerns now and in the future.

About the Study

Researchers from the University of Colorado Boulder followed 123 Hispanic mother-child pairs in Southern California. They measured the growth of the infants during the first six months of life during in-person visits. Using the mothers’ addresses, researchers then estimated the amount of air pollution each child endured. The babies with the greatest exposure to air pollution not only grew faster during the time period, but also accumulated more body fat. In fact, studies have shown that fetal exposure to air pollution can result in low birth weight. That low weight, in turn, puts the child at greater risk for infant rapid weight gain after birth. “This is significant because previous studies have linked faster weight gain in the first 6 months of life with obesity in childhood,” states William Patterson, the first author of the study and a PhD student in the Department of Integrative Physiology at University of Colorado Boulder. This study focused on Hispanic children, recognizing that they tend to have higher levels of exposure to air pollutants. Because of the focus on one ethnicity, more research is needed to corroborate the results with other ethnic groups. The results, however, are still impactful. “Gaseous pollutants, like nitrogen dioxide and ozone, as well as particulate matter, can induce inflammation and oxidative stress in humans and are most harmful during critical life stages like pregnancy and developmental periods,” notes Tanya L. Alderete, PhD, assistant professor in the Department of Integrative Physiology at University of Colorado Boulder and senior author of the study. Expectant mothers and people worldwide continue to breathe in hazardous particles. According to the American Lung Association’s “State of the Air” 2021 report, over 135 million people, which accounts for more than 40% of Americans, live in areas with unhealthy levels of particulate pollution. It’s a dangerous trend that impacts us all and can start its devastating impact while a child is still in the womb.

Why Rapid Weight Gain Matters

Babies should gain double their birth weight by approximately the five-month-old mark. By the time a child is a year old, he or she will triple their birth weight. Those normal milestones are signs of healthy growth, and necessary for appropriate development. But when growth happens too quickly, problems can develop. Rapid weight gain in babies is not only linked to an increased risk of childhood obesity but also the potential later in life for increased blood pressure, as well as diabetes. Obesity can also cause children to experience high blood pressure. In fact, childhood obesity is a medical problem experienced by 1 in 5 children and adolescents in America. Eating too much of the wrong types of food can lead to obesity. Genetics can also play a part. So can the world around you. “We like to think that obesity can be addressed simply by having a better diet and some exercise, but it’s so much more complicated than that. Genetics, inflammation, and as we can see here, the environment we are raised in, can all have an impact on obesity,” explains Armeen Poor, MD, clinical assistant professor of medicine at New York Medical College, and an attending physician in the division of pulmonary and critical care at Metropolitan Hospital in New York City.

How to Protect Yourself

We don’t always have control over the air around us, or when and where pollutants are released. But there are some recommendations that can help:

Live farther away from busy interstates, if possible. Avoid walking near busy roadways during high traffic times.   Avoid cigarette smoke at all costs—for yourself and from others.Be cognizant of the air quality around you. Weather broadcasts and phone apps offer this information.Keep your windows closed on days when air quality is low.

Be sure to consult your physician if you have any concerns about the impact of the air quality in your area on your baby. You can also help to counter the negative effects of air pollution by eating a healthy diet full of fruits and vegetables. Making the extra effort now can make a world of difference in their lives and health later.