by Lisa Egan
A new study revealed some disturbing information about common food additives called emulsifiers: they may promote inflammatory bowel diseases including ulcerative colitis and Crohn’s disease as well as a group of obesity-related conditions.
The study, which was published in the journal Nature today, was led by Georgia State University Institute for Biomedical Sciences’ researchers Drs. Benoit Chassaing and Andrew T. Gewirtz, and included contributions from Emory University, Cornell University and Bar-Ilan University in Israel.
Emulsifiers are chemicals added to many food products to improve texture and extend shelf life. In experiments with mice, researchers found that emulsifiers can change the species’ composition of gut bacteria and induce intestinal inflammation.
That inflammation is associated with serious disorders and diseases, reports Science Daily:
Inflammatory bowel disease (IBD), which includes Crohn’s disease and ulcerative colitis, afflicts millions of people and is often severe and debilitating. Metabolic syndrome is a group of very common obesity-related disorders that can lead to type-2 diabetes, cardiovascular and/or liver diseases. Incidence of IBD and metabolic syndrome has been markedly increasing since the mid-20th century.
Gut microbiota refers to the 100 trillion diverse bacteria that reside in the human intestinal tract. This microbiota is disturbed in IBDs and metabolic syndrome.
Chassaing and Gewirtz’s findings suggest emulsifiers might be partially responsible for this disturbance and the increased incidence of these diseases:
“A key feature of these modern plagues is alteration of the gut microbiota in a manner that promotes inflammation,” says Gewirtz.
“The dramatic increase in these diseases has occurred despite consistent human genetics, suggesting a pivotal role for an environmental factor,” says Chassaing. “Food interacts intimately with the microbiota so we considered what modern additions to the food supply might possibly make gut bacteria more pro-inflammatory.”
Here’s how the study was conducted:
The team fed mice two very commonly used emulsifiers, polysorbate 80 and carboxymethylcellulsose, at doses seeking to model the broad consumption of the numerous emulsifiers that are incorporated into almost all processed foods.
They observed that emulsifier consumption changed the species composition of the gut microbiota and did so in a manner that made it more pro-inflammatory. The altered microbiota had enhanced capacity to digest and infiltrate the dense mucus layer that lines the intestine, which is normally, largely devoid of bacteria. Alterations in bacterial species resulted in bacteria expressing more flagellin and lipopolysaccharide, which can activate pro-inflammatory gene expression by the immune system.
Such changes in bacteria triggered chronic colitis in mice genetically prone to this disorder, due to abnormal immune systems. In contrast, in mice with normal immune systems, emulsifiers induced low-grade or mild intestinal inflammation and metabolic syndrome, characterized by increased levels of food consumption, obesity, hyperglycemia and insulin resistance.
The team is now testing additional emulsifiers and designing experiments to see how the additives affect humans. If similar results are obtained, it would suggest that this class of food additive may play a role in the epidemic of obesity, its interrelated consequences, and a range of diseases associated with chronic gut inflammation.
Incidence of inflammatory bowel disease and metabolic syndrome started rising in the mid-20th century – right around the time that food manufacturers began widespread emulsifier use, the researchers said:
“We were thinking there was some non-genetic factor out there, some environmental factor, that would be explaining the increase in these chronic inflammatory diseases,” Georgia State immunologist Andrew Gewirtz said.
“And we thought that emulsifiers were a good candidate because they are so ubiquitous and their use has roughly paralleled the increase in these diseases. But I guess we were surprised at how strong the effects were.”
Research suggests that the relationship between gut flora and humans is a mutualistic, symbiotic relationship. This means that it is a mutually beneficial relationship – the microbes need us, and we need them.
Your gastrointestinal system doesn’t simply move food through your body – it does so much more: it synthesizes vitamins and nutrients, metabolizes some medications, maintains gut functioning, and enhances the functioning of your immune system.
Having a healthy digestive system is important because a healthy system filters out things that can damage it (like that bad bacteria, toxins, chemicals, and waste products). It also helps us absorb and deliver the good stuff like nutrients from our food.
Research continues to reveal more dangers to our digestive systems: last year, scientists at Leipzig University discovered that glyphosate — the main ingredient in Big Agra giant Monsanto’s Roundup herbicide — actually kills the healthy bacteria in the gut when ingested.
We also know that inflammation can cause health problems that aren’t directly linked to the gut. It is the likely cause of many conditions, including arthritis, asthma, cancer, chronic pain, depression, headaches, and heart disease.