Food Packaging can Contribute to Weight Gain

26 Jan 2016 --- A German study has now shown that plasticisers (also known as phthalates), which are found in most food products, can enter the body, disrupt hormone production, and cause people to gain weight.

Martin von Bergen, Head of the Department of Molecular Systems Biology at the Helmholtz Centre for Environmental Research (UFZ), and his UFZ team performed the study in collaboration with researchers Nora Klöting and Matthias Blüher (spokespersons for the Collaborative Research Centre "Obesity Mechanisms") from the Integrated Research and Treatment Center (IFB) Adiposity Diseases at the University of Leipzig and the University Hospital Leipzig. They have been able to demonstrate for the first time that plasticisers can have that effect on the body. Their collaborative study, which is published in the PLOS ONE journal, shows that the phthalate DEHP leads to weight gain and reveals the metabolic processes involved.

Phthalates are used as plasticisers in polymer processing to make plastics soft, flexible or tensile. Plasticisers are added to food packaging, cables and various other products in order to make them more flexible and easier to handle. They are controversial because they can emerge from the material and enter the body through the skin or in food, where they can disrupt hormone production.
Phthalates are mainly transferred from the food packaging of fatty products, e.g. cheese or sausages. Von Bergen added: "We currently know very little about how exactly phthalates have an effect within the body and how they can influence body weight - we intended to evaluate this in our study."

In Germany, one in two adults is overweight. This figure is as high as 15% in children and young people. "The figures are alarming" said von Bergen. "Because every kilo over the ideal weight increases the medical risk of cardiovascular disease, joint damage, chronic inflammation and cancer and the number of overweight people is constantly increasing all over the world." The development of overweight has many causes: in addition to bad dietary habits and a lack of exercise, genetic factors doubtlessly play a role. Certain environmental pollutants such as phthalates, may also be partly responsible for the development of overweight. "Correlations between increased phthalate concentrations in the human body and the development of overweight have already been proven in epidemiological studies and should be analyzed in more detail" von Bergen added.

The number of obese people is also increasing globally. "In addition to bad eating habits and lack of exercise, genetic factors also play a role" said von Bergen. He added that "certain environmental factors, such as phthalates, can contribute to the development of obesity".

The researchers tested their theory on mice, adding the DEHP plasticiser to their drinking water. Their results showed increases in weight, especially in female mice. Blood tests also revealed disrupted glucose metabolism and increased levels of unsaturated fat in the bloodstream.

"Phthalates affect hormonal balance greatly. Even in low concentrations, they can cause significant changes, such as weight gain" said von Bergen. However, the question of how plasticisers actually change hormonal balance and cause weight gain is still unclear. Researchers are still pursuing the answer to this particular quandary.

By Kerina Tull