Two common food additives known as emulsifiers – compounds which preserve foods like mayonnaise and stop them from separating – could be seriously messing with the bacteria in your gut, according to a recent study.
The emulsifiers the study looked at are known as carboxymethycellulose and polysorbate-80, and both are frequently added to processed foods.
It turns out that these additives can cause serious disruptions in the gut bacteria of mice, even in relatively low concentrations.
The Significance Of Gut Bacteria
Most people don’t think a lot about the colonies of bacteria that live in their gut, but these colonies are vitally important to the overall function of our entire bodies, from weight management(1) to the immune system(2) to our digestive health(3).
The new study, published the journal Nature, seeks to help explain why processed foods contribute so much to weight gain(4) – as well as why inflammatory conditions like irritable bowel syndrome, or IBS, have increased significantly in recent years(5).
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How Emulsifiers Affect Our Guts
To better understand how emulsifiers can affect gut bacteria, researcher Andrew Dewirtz at Georgia State University added the two common emulsifiers to lab mice’s drinking water. All the mice were fed the same diet, but were fed different concentrations of emulsifiers.
What the researchers eventually discovered was that even healthy mice who had been fed emulsifiers became obese, developing such metabolic problems as glucose intolerance.
But that wasn’t all – they also tested the emulsifiers on mice that were genetically engineered to be predisposed to inflammatory gut diseases, finding that these mice suffered flare ups of inflammatory bowel disease after being fed the emulsifiers.
These results were consistent even in mice who were fed the lowest concentration of emulsifiers – about one-tenth of the concentration that the FDA permits in food products.
Reporting on the study for Nature, Sara Reardon writes:
“Gewirtz and his colleagues suspect that the emulsifiers can break down the heavy mucus that lines the mammalian gut and prevents bacteria from coming into contact with gut cells. If this happens, the bacteria cause inflammation in the gut, which can also lead to changes in metabolism.”(6)
The Next Steps
In the past 50 years, no study has managed to conclusively prove that these additives pose a significant risk to human health. But armed with this recent study, researchers are calling for more trials to be conducted on the subject.
Some researchers believe that if large-scale population studies were to look at changes on the gut bacterial level, they would find that such additives do pose a risk to our health after all.
Some studies done on other common food additives, such as artificial sweeteners, have proven recently that these common ingredients can also negatively impact our gut bacteria(7).
What is clear to most researchers studying the effects of food additives is that the less processed food you eat, the better.