Emulsifiers, which are common ingredients in processed food added to stabilize texture, can wreak havoc on mucous membranes that keep gut bacteria from reaching the intestinal wall, according to work published in Nature (2015, DOI: 10.1038/nature14232). In a study of mice, researchers found that gut bacteria that have easy access to the intestinal wall thanks to two common food emulsifiers can cause intestinal inflammation and obesity-associated diseases. “While additional studies will be needed to determine if carboxymethylcellulose, polysorbate 80, and/or other emulsifiers impact human health, our observations in mice suggest the possibility that dietary emulsifiers may have contributed to the post-mid-20th-century increase in incidence of inflammatory bowel disease, metabolic syndrome, and perhaps other chronic inflammatory diseases,” notes the team of researchers led by Georgia State University’s Andrew T. Gewirtz. The team notes that many common food additives have been deemed by regulatory agencies as GRAS (generally recognized as safe) without much toxicity testing. And if tests were performed, they focused on cancer or acute toxicity. “Our data suggest such testing may be inadequate,” they note.