Emulsifiers, commonly added to many processed foods in order to add texture and extend shelf life, could be altering the gut microbiota composition and cause intestinal inflammation that leads to inflammatory bowel disease (IBD) and metabolic syndrome, a new study suggests.

The research, led by Georgia State University Institute for Biomedical Sciences, tested the effects emulsifiers have on the gut microbiota in mice. The study concluded that emulsifiers might be partially responsible for the disturbance and increased incidence of IBD and metabolic syndrome.

According to researchers, the term “gut microbiota” refers to the diverse population bacteria that inhabit the intestinal tract. Gut microbiota are disturbed in IBD and metabolic syndrome. IBD includes Crohn’s disease and ulcerative colitis while metabolic syndrome is a group of common obesity-related disorders that can lead to type-2 diabetes, cardiovascular and/or liver diseases.

Researchers say the incidence of both of these disorders have been increasing since the mid-20th century.

“The dramatic increase in these diseases has occurred despite consistent human genetics, suggesting a pivotal role for an environmental factor,” said Benoit Chassaing, lead researcher. “Food interacts intimately with the microbiota so we considered what modern additions to the food supply might possibly make gut bacteria more pro-inflammatory.”

Two common emulsifiers, polysorbate 80 and carboxymethylcellulsose, were fed to the mice. Researchers observed that consumption of the emulsifiers changed the species composition of the gut microbiota in a way that made it more susceptible to inflammation.

 The research team is now testing other emulsifiers and designing experiments to study the effects emulsifiers have on humans.