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Processed Foods Linked to Harmful Chemicals

There is now another compelling reason to avoid some processed foods, with the discovery of a link between an unhealthy diet and exposure to potentially harmful phthalates used in plastic food wrappings.

Peter Bai, a University of Adelaide PhD student who was lead author of the research published in PLOS ONE, says that although people are exposed to phthalates ubiquitously, international studies have concluded that diet is the major contributor to phthalate exposure.

“Phthalates are widely used in a variety of industrial and consumer products to increase the transparency, flexibility and durability of plastic,” Bai says. “They are also used in personal care products, medical devices, medications and dietary supplements.”

The research was the first population study to investigate the association between socio-demographic status, lifestyle factors, dietary patterns and exposure of phthalates in Australian men. “Phthalates were detected in 99.6% of the study participants, demonstrating that there is high exposure to the chemicals in urban South Australia, and this is probably representative of all urban Australian areas,” Bai says.

“We didn’t find a difference in the levels of phthalates detected according to socio-demographic status. However, participants who ate less fresh fruit and vegetables and more processed and packaged foods, and drank carbonated soft drinks, had higher levels of phthalates in their urine,” he says.

Senior Research Fellow Dr Zumin Shi adds that we don’t know exactly what effect phthalates have on the body, but we do know that the chemicals impact the endocrine system. “In recent times there have been increased concerns from the public about phthalates and an association with detrimental health effects such as obesity, diabetes and cardiovascular disease,” Shi says. “And in this study we found that phthalates are associated with obesity.”

Bai says that the best way to limit exposure to phthalates is to consume more fresh vegetables, fruit, nuts and fish, and less high-fat, packaged and processed foods. “The primary pathway for phthalates exposure is through consuming contaminated food, which is why diet is so important. Phthalates can also be absorbed by inhalation of air or dust containing the chemicals, and through the skin, but the exposure is a lot less than if it is consumed.”