Shocking new findings suggest a common food additive could be linked to cases of inflammatory bowel disease and metabolic syndrome.

Emulsifiers, which are added to almost all processed foods to preserve and aid in texture, were found to have an influence on gut microbiota composition, Georgia State University reported. These changes can lead to intestinal inflammation and related conditions. The researchers believe the used of these additives could be partially responsible for an increase in the prevalence of these diseases, which included type-2 diabetes, Crohn's disease, and ulcerative colitis.

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

To make their findings, the researchers fed mice two common emulsifiers, polysorbate 80 and carboxymethylcellulsose, at doses similar to what would be consumed by humans in everyday life. They observed that the consumption of these additives changed the composition of the gut microbiota in a way that promoted inflammation. The altered bacteria had a greater ability to move into the mucus layer surrounding the intestine, which is usually only sparsely populated with these organisms. The bacteria also expressed more flagellin and lipopolysaccharide, which can activate pro-inflammatory gene expression.

These significant changed were observed to trigger chronic colitis in mice genetically prone to this disorder as a result of abnormal immune systems; mice with normal immune systems that consumed the emulsifiers showed a tendency towards low-grade or mild intestinal inflammation and metabolic syndrome.

The researchers are now testing the effects of other emulsifiers and working to gain a better understanding of how these additives specifically effect humans.

"We do not disagree with the commonly held assumption that over-eating is a central cause of obesity and metabolic syndrome," said Biomedical Sciences researcher Andrew T. Gewirtz. "Rather, our findings reinforce the concept suggested by earlier work that low-grade inflammation resulting from an altered microbiota can be an underlying cause of excess eating."

The findings were published in a recent edition of the journal Nature.