Several studies have linked the compound chemical bisphenol A, or BPA to potential health problems including asthma and behavior problems in children.
Now a new study finds a link between the chemical and obesity in girls. The common chemical is banned in baby bottles and sippy cups but is still in some plastic containers and in the lining of cans. Last year, the U.S. Food and Drug Administration officially banned BPA from baby bottles and sippy cups, though manufacturers had already stopped using it. The agency declined to ban it from other food containers, pending further research.
In a new study published on Wednesday in the journal PLoS One, researchers measured BPA levels in the urine of more than 1,300 children in China and compared those levels to their body weights.
"Eating too much and exercising too little are important factors," said Dr. De-Kun Li, a reproductive and perinatal epidemiologist at Kaiser Permanente in Oakland, California. "But they cannot explain the steep increase in the obesity rate the last three decades. We haven't really changed our eating habits and exercise that much."
Li and colleagues looked at 1,326 school-age children in Shanghai, China, and measured BPA levels in their urine. In girls ages 9 to 12, higher BPA urine levels were associated with a doubled risk of obesity. And as BPA urine levels increased, so did the girls' obesity risk - measured using their weight in reference to weight distribution in the population.
Interestingly enough, the study found that only girls between 9 and 12 were affected, with girls outside this age bracket succumbing to the same fate. According to the CDC , almost everyone living in the United States over age 6 has BPA traceable in their urine. BPA is associated with a variety of other health problems besides obesity, which includes low birth weight, asthma , and sexual dysfunction in men.
Li said is hopeful this study will bring awareness to the potential health effects of BPA. "It took 50 years from epidemiological research until finally the surgeon general said smoking is bad," said Li. "During that time you can't imagine how many unnecessary deaths there were."
Concrete proof linking BPA's to obesity is still building, but Li say the latest study should at the very least establish BPA as a major health concern for child obesity.