Are Emulsifiers Making People Fatter?

A recently published study by university researchers links common food additives to gastrointestinal problems and obesity in mice.

In the study, researchers fed mice the emulsifiers polysorbate 80 and carboxymethyl cellulsose. Emulsifiers are added to nearly all processed foods as a preservative or to enhance texture.

As a result, the mice experienced disturbances in their intestinal bacteria, which made the "gut microbiota" more prone to inflammation. Those changes triggered chronic colitis in mice with genetically abnormal immune systems; mice with normal immune systems, meanwhile, experienced low-grade inflammation and metabolic syndrome, leading to increased food consumption, obesity, hyperglycemia and insulin resistance.

The scientists, led by a team from Georgia State University, said further testing of the effects of emulsifiers on humans could demonstrate a link between food additives, the obesity epidemic and gastrointestinal diseases.

"We do not disagree with the commonly held assumption that over-eating is a central cause of obesity and metabolic syndrome," said Andrew Gewirtz, one of the lead researchers. "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."