Dietary emulsifiers and gut bacteria linked to colitis and obesity

Posted on Sat, 11 Apr 15

Artificial food additives may be allowing your gut bacteria to break through a protective mucus layer in your gut and cause disease throughout your body.

A new study in the journal Nature has made a startling discovery; common food additives may be causing a unique type of bacterial imbalance in your gut that is linked to disease.

It is well known now that alterations in our gut bacteria can influence our health, and modern diets (e.g. high-fat, low-fiber foods) and lifestyle factors (e.g. lack of exercise, antibiotic use) are all known to play a role.

Deep in our digestive system we protect our selves from the 2-3 kilograms of bacteria that reside there by a natural layer of mucus that lines our gut wall and prevents them from getting too close.

Well it turns out a very common class of food additives known as the ‘emulsifiers’ may not only be emulsifying our food, but emulsifying our protective mucus and letting the bacteria get far too close for comfort.

It was discovered that relatively low concentrations of two commonly used emulsifiers (carboxymethylcellulose and polysorbate-80) induced low-grade inflammation and obesity/metabolic syndrome in mice and promoted robust colitis in mice predisposed to this disorder.

Image: Compared to water, emulsifiers carboxymethylcellulose (CMC) and polysorbate-80 (P80) break down protective mucus (green) and allow bacteria (red) to get close to the gut wall (purple).

This finding raises the possibility that one reason modern processed foods are linked to inflammatory bowel disease and obesity is that they are breaking down our mucosal barrier, disrupting gut bacterial balance, increasing inflammation and driving the development of disease.

“While additional studies will be needed to determine if CMC, P80 and/or other emulsifiers impact human health, our observations in mice suggest the possibility that dietary emulsifiers may have contributed to the post-mid-twentieth-century increase in incidence of inflammatory bowel disease, metabolic syndrome, and perhaps other chronic inflammatory diseases” commented the researchers involved in the study.

Reference:  

Chassaing B, et al. Dietary emulsifiers impact the mouse gut microbiota promoting colitis and metabolic syndrome. Nature. 2015 Mar 5;519(7541):92-6