A new study revealed that regular exposure to a common food additive promotes the development of intestinal inflammation and colorectal cancer.

The study, published in the journal Cancer Research, showed that regular consumption of the food additive emulsifiers can alter the intestinal micorbiota in mouse models, exacerbating tumor development.

"The incidence of colorectal cancer has been markedly increasing since the mid-20th century," said Dr. Emilie Viennois, an assistant professor at Georgia State University's Institute for Biomedical Science and lead author of the study, in a statement. "A key feature of this disease is the presence of an altered intestinal microbiota that creates a favorable niche for tumorigenesis."

It has been previously accepted that intestinal microbiota play a crucial role in the development of colorectal cancer and other diseases, including Crohn's disease and ulcerative colitis. Furthermore, low-grade inflammation has been previously linked to altered gut microbiota composition and metabolic diseases. Additionally, low-grade inflammation has been observed in many cases of colorectal cancer.

For the study, the researchers fed mice with two very commonly-used emulsifiers, polysorbate 80 and carboxymethylcellulose. The researchers controlled the dosage given to the mice to mimic the broad consumption of the numerous emulsifiers incorporated into majority of the processed food.

The researchers observed that the consumption of emulsifiers led to drastic changes in the species composition of the gut microbiota. By altering the diverse population of microorganisms living in the intestines, the emulsifiers promoted a pro-inflammatory environment, creating a niche favorable to caner induction and development.

The alterations of bacterial species in the gut micorbiota resulted in the increase expression of flagellin and lipopolysaccharide, which activate pro-inflammatory gene expression by the immune system. The researchers found that the creation of pro-inflammatory environment associated with an altered microbiota species is enough to make an individual more susceptible to developing colonic tumors.

This findings support the concept that low-grade gut inflammation caused by alterations in the host-microbiota interactions could promote colon carcinogenesis.