Food Packaging, BPA, and Childhood Obesity: What's the Connection?

More than 90 percent of Americans over the age of 6 have detectable levels of Bisphenol-A (BPA) in their blood, according to the Centers for Disease Control and Prevention. And while BPA may have been removed from baby bottles and sippy cups, the controversial chemical is still a ubiquitous part of modern life. And now researchers from NYU say continued exposure to BPA may be a hidden factor in the nation's childhood obesity crisis.

In the new study, researchers measured levels of BPA in urine samples from more than 2,800 American children and teens. While approximately 92 percent of study participants had detectable levels of BPA in their urine, those with the highest levels were 2.6 times more likely to be obese than those with the lowest levels.

At first glance, the connection between obesity and BPA in food packing makes biological sense, says study lead author Dr. Leonardo Trasande, an associate professor of pediatrics and environmental medicine at the NYU School of Medicine. In animals, studies have shown the chemical makes fat cells bigger and gets in the way of a certain protein that helps break down sugars and fats. BPA also appears to disrupt hormones that play a key role in energy balance.

But what about the food found inside the cans and plastic containers? Critics of the study say it's the food, not food packaging, that's making kids obese, pointing out that it could be that obese children are simply more likely to consume processed, packaged foods.

As Charles Santerre, professor of food toxicology at Purdue University in West Lafayette, Indiana, tells ABC News, "America is obese, not because of BPA, but because we consume more calories than we burn."

In either case, there's a effective solution: eat fresh food. Another study found that families who took part in a "fresh foods intervention" cut their BPA levels by about 50 percent just by dropping pre-packaged foods from their diets.