Food Emulsifiers and the Microbiome

Experiment by Nora Martin
Experiment by Nora Martin

Beverly Hobbs

                                                                                                                                                                  July 17, 2015

Recently, my niece Nora and I did a science experiment about mold growing on bread that is exposed to various germs from hands that had touched various dirty surfaces. To our surprise, none of our samples grew any mold! See bread. Why was this? What is going on with food additives and what effect do they have on the microbiome and our health? As I browsed through Google, I found a recent article (and lots of press about the research described) linking emulsifiers to inflammatory bowel diseases. The studies were done in mice and the specific emulsifiers used were carboxymethylcellulose and polysorbate-80. Both are commonly used to smooth the texture of foods such as ice cream, mayonnaise, and to keep foods that tend to separate homogenous. Yum!

Benoit Chassaing at Georgia State University fed mice the emulsifiers in large doses (note, the amounts are equal to how much a person would eat if the only thing they ate was ice cream).   Mice fed emulsifiers had less diversity in their microbiome and the microbes had moved closer to the cells lining the gut. These mice also showed more signs of intestinal inflammation. In certain mice that were bred to be more susceptible to gut diseases, the mice developed inflammatory bowel disease (IBD) at a rate more frequent and more severe than typical.

In heathy guts, there is a layer of mucus that lines the gut and prevents bacteria from coming into contact with the gut cells. They believe that the heavy mucus is broken down by emulsifiers, allowing the bacteria to get closer to the gut cells and cause inflammation.

In addition to inflammation, feeding healthy mice lots of the emulsifiers lead to increased weight gain and adiposity (more body fat) and decreased ability to regulate blood sugar levels. These kinds of symptoms are similar to what is observed in obesity-associated diseases.

The authors of the study suggest that the use of emulsifying agents in food may contribute to obesity and chronic inflammatory diseases in people. We have a program here at UMass Med that is looking at the relationship between diet and various gastrointestinal disorders. Our dieticians specialize in creating palatable recipes (without additives!) that facilitate gut healing while maintaining nutritional balance for patients with IBD, Crohn’s and Colitis. Watch here as we share with you more of their recipes over time.


Dietary emulsifiers impact the mouse gut microbiota promoting colitis and metabolic syndrome: Benoit Chassaing,Omry Koren,Julia K. Goodrich,Angela C. Poole,Shanthi Srinivasan,Ruth E. Ley& Andrew T. Gewirtz Nature 519, 92–96 (05 March 2015) doi:10.1038/nature14232;


Can dietary fiber fight obesity?

produceby Meghan McGillin, UMass Amherst
undergraduate student,

Scientists and clinicians have been interested in studying dietary fiber’s potential in treating or preventing obesity. Obesity is a big health problem, afflicting 500 million adults worldwide.

Familiar such as whole grains, nuts, legumes, fruits and vegetables.are naturally high in dietary fiber. Dietary fiber gives plant-based foods their structure fiber-rich foods need more chewing to break up the rigid structure of the plant cell wall. Just think about the work that goes into chewing an apple versus eating a piece of cheese. That extra chewing is important! Chewing takes time and makes more saliva. This helps the chewer take up fewer calories over a longer period and feel more full. Simply eating more fiber can help lower weight gain and thus lower the risk of health complications such as type II Diabetes Mellitus and cardiovascular diseases.

But there’s more! Fiber is a vital component of our diet, and has been linked to preventing a range of illnesses and conditions. Unlike sugar and starch, fiber is unique because our own digestive enzymes are unable to break fiber down into simpler sugars. We need the beneficial microbes living in our guts to break up fiber for us. These microbes have the enzymes to digest fibers and when they do they produce nutrients and byproducts that are helpful for our metabolism and immune systems. In fact, scientists have learned that having certain types of microbes reduce the risk of developing metabolic syndrome and other chronic diseases.

To fully understand the anti­obesity effects of fiber, it is necessary to examine the role of our resident gut microbiota as a major contributor to our metabolic well-being. The good news is that it appears diet changes can promote a more protective microbiome. Adding more fiber to one’s diet benefits both the person and their microbes.