Children with higher levels of BPA (bisphenol A) may be more likely to be obese, according to a study published today in The Journal of the American Medical Association.
"To our knowledge," the authors write, "this is the first report of an association of an environmental chemical exposure with childhood obesity in a nationally representative sample."
As the Surprising Science blog of the Smithsonian describes the study: "The researchers pulled data from the 2003 to 2008 National Health and Nutrition Examination Surveys, and after controlling for differences in ethnicity, age, caregiver education, income level, sex, caloric intake, television viewing habits and other factors, they found that children and adolescents with the highest levels of BPA in their urine had a 2.6 times greater chance of being obese than those with the lowest levels. Overall, 22.3 percent of those in the quartile with the highest levels of BPA were obese, compared with just 10.3 percent of those in the quartile with the lowest levels of BPA."
USA Today brings out a broader picture citing Linda Birnbaum, director of the National Institute of Environmental Health Sciences, who was not involved in the study, on how the study adds to a long list of damning information about BPA:
Taken alone, the study might not make much of a case against BPA, Birnbaum says. But it's more powerful in light of the long list of earlier experiments in animals and cells linking BPA to obesity, diabetes, breast and prostate cancers, behavior problems and other issues, especially in animals exposed before birth.
In recent years, evidence has linked BPA to a variety of human ailments:
-- A study published in Pediatrics last year found that girls exposed before birth to high levels of BPA were more likely to be anxious, depressed and hyperactive at age 3.
-- Men with higher levels of BPA were two to four times more likely than others to have problems with sperm quality and quantity, according to a 2010 study in Fertility and Sterility.
-- A 2008 study in JAMA linked high BPA levels in adults to diabetes, heart disease and abnormal liver function.
Public health watchdog Environmental Working Group says it's beyond time to act on the dangers of BPA.
"How many more serious health problems that afflict children and are associated with exposure to BPA have to pile up before the FDA restricts its use from food, beverage and infant formula packaging?" said Environmental Working Group Senior Research Analyst, Sonya Lunder. "This latest research implicates BPA in one of the most serious public health crisis young people in the United States now face. And while there are many factors surrounding the obesity epidemic, the FDA could actually take immediate steps to address one possible cause by removing this toxic chemical from the nation's food system, beginning with baby formula."
Lead investigator Dr. Leonardo Trasande says that "Clearly unhealthy diet and poor physical activity are the leading factors contributing to obesity in the United States, especially in children," but also adds that the results should cause a rethink about the obesity epidemic. “Our findings further demonstrate the need for a broader paradigm in the way we think about the obesity epidemic,” said Trasande. “Unhealthy diet and lack of physical activity certainly contribute to increased fat mass, but the story clearly doesn’t end there.”