WVU research: BPA may contribute to diabetes

About 10 percent of cases could potentially be prevented

MORGANTOWN, W.Va. – Adults with higher levels in their urine of a chemical that’s commonly found in food and beverage packaging could be at increased risk of developing diabetes, according to new research from Anoop Shankar, M.D., Ph.D., an epidemiologist and associate professor in the West Virginia University Department of Community Medicine.

Bisphenol A (BPA) is a widely used chemical in the manufacturing of polycarbonate plastics and epoxy resins and is found in a variety of products ranging from canned soup to infant formula. Human exposure to BPA is believed to be mainly through dietary intake, though the chemical can also enter the body through dental sealants, inhalation of household dusts and through the skin. Previous studies have shown that BPA mimics hormones, leading to negative health effects. Dr. Shankar said that the latest research findings were consistent with leads from previous animal studies.

“We were not entirely surprised,” Shankar said. “There was strong evidence that even a low level of BPA exposure was associated with insulin resistance, hyperglycemia and dysfunction within the cells that secrete insulin in the pancreas.”

Shankar’s study analyzed a large sampling of existing urinary BPA levels and diabetes mellitus data in the National Health and Nutritional Examination Survey 2003-2008. Bisphenol A is present in the urine of virtually all Americans, and urinary BPA levels were found to be associated with diabetes mellitus regardless of factors such as age, gender, race/ethnicity, body mass index, alcohol intake and cholesterol levels.

“If our results are true, we estimate that based on population attributable risk calculations, about 10 percent of diabetes could be prevented by limiting exposure to BPA,” Shankar said.

Although completely eliminating exposure to BPA may not be possible, Shankar said there are steps everyone can take to reduce exposure to the chemical.

“People could avoid using canned foods, particularly canned soups, juices and beans, which have all been shown to have high levels of BPA, unless they are explicitly stated to be BPA-free,” he said. “Use foods that have been preserved in glass, porcelain or stainless steel whenever possible. Fresh fruits and vegetables from a local farmer’s market may have less BPA, as they are not packaged in plastic while transported.”

Though the United States Environmental Protection Agency declared bisphenol A “a chemical of concern” in 2010, the substance is still widely used in food and beverage packaging. Some states have pursued legislation to ban the sale of some products that may leach BPA into their contents, like baby bottle and training cups. Though more human studies are needed to support his findings, Shankar believes such laws could make a difference.

“Ultimately, regulation is the best way to keep these chemicals out of our systems,” he said. “In some countries, such as Canada, governmental agencies have listed BPA as toxic to human health.”

The study was published in the “Journal of Clinical Endocrinology and Metabolism,” a leading endocrinology journal.