BPA Link to Obesity Debated While Childhood Exposure Declines
A new analysis shows that exposure to BPA in children has declined since 2003, while other research is stirring debate about the link of BPA (bisphenol A) in plastics to obesity. Coincidentally, recent reports have also shown a leveling or decline in obesity rates for young children thought to be most susceptible to the metabolic effects of BPA exposure.
In the latest issue of Epidemiology, Ellen Wells and colleagues at Case Western Reserve University report that data from 10,415 participants in the NHANES panel showed declines in urinary BPA levels for children 6-11 years of age from 2003 to 2006 and 2010. Although levels declined in all age groups between 2003 and 2006, the declines did not continue in people 12-19 or over 20 years old.
BPA is the chemical used to make plastic found in many food containers, such as vegetable and soup can linings, aluminum pop-top soda and beer cans, and much more. Knowledge about endocrine disruptors such as BPA is only recently accumulating. BPA finds its way into the environment and CDC estimates that 93% of Americans have this chemical in the blood.
Earlier, Trasande and colleagues found an association between BPA and BMI (body mass index) outcomes for children and adolescents in a study published in the Journal of the American Medical Association. The JAMA study found that high urinary BPA concentrations were associated with increased obesity in children after taking into account a number of risk factors for obesity.
Trasande used data from the 2003-2008 NHANES study to examine urinary BPA levels and prevalence of obesity in children and adolescents age 6 – 19 years. The national sample of 2,838 participants was randomly selected for measurement of urinary BPA concentration. BMI was used to identify obesity. The researchers found BPA concentration was significantly associated with obesity in children and adolescents. Although the results showed a strong association, as with any such study, these results do not prove that BPA exposure causes obesity.
Meanwhile, a new animal study failed to replicate earlier animal studies suggesting that BPA exposure causes greater susceptibility to obesity and type-2 diabetes. And so a healthy scientific debate continues.
Click here to read the Wells publication in Epidemiology, here to read a review in the latest issue of Nature Reviews Endocrinology, here to read an abstract of the Trasande study, and here to read a report of the more recent animal study.
Warhol Soup Cans at the Royal Scottish Academy, image © SixSigma / Wikimedia Commons