Common Food Additives May Be Making Us Fat
Science has given wary consumers another reason to avoid some of those tongue-twisting ingredients listed on the packaging of countless products in the average American grocery store. In a study published this week in Nature, researchers say they’ve found evidence that two commonly used emulsifiers in processed foods may be linked to the rise in obesity and to certain chronic digestive disorders.
The team of researchers, led by two scientists at Georgia State University, wanted to see what impact the synthetic emulsifiers polysorbate-80 and carboxymethylcellusose might be having on the trillions of bacteria that make up the gut microbiota and are essential for healthy digestion. Both emulsifiers are found in a slew of products—most notably ice cream and other frozen dairy desserts. But they can also crop up in everything from canned soup and salad dressing to frozen entrées and cream cheese (and even sunscreen and hemorrhoid cream, but we won’t think about that).
The scientists fed the emulsifiers to mice at doses comprable to what your average person might consume. What they found was that the gut bacteria of the mice that were given the emulsifiers were altered in a way that made the digestive tract of the animals more prone to inflammation—which is linked to the onset of metabolic syndrome, a group of common obesity-related disorders that can lead to type 2 diabetes as well as heart and liver disease. In mice genetically predisposed to inflammatory bowel disease, the changes to their gut bacteria appeared to trigger that disorder.
That would seem significant, as public health experts have struggled to thoroughly explain the alarming spike in obesity rates in America and in other developed countries. While many say overeating and a relative lack of physical activity are leading factors, they argue those issues alone are not enough to explain the obesity epidemic and the proliferation of related health problems.
“The dramatic increase in these diseases has occurred despite consistent human genetics, suggesting a pivotal role for an environmental factor,” Benoit Chassaing, one of the study’s lead researchers, said in a statement. “Food interacts intimately with the microbiota, so we considered what modern additions to the food supply might possibly make gut bacteria more pro-inflammatory.”
We may not give much thought to the estimated 100 trillion organisms that call us home, but when it comes down to it, we’re more bacteria than human. Bacteria outnumber our own cells 10 to one, and scientists are increasingly coming to understand that messing with all those tiny organisms may be causing a host of big problems. A blockbuster essay published in The New York Times last year by science writer Pagan Kennedy looked at the research suggesting our overreliance on antibiotics may be linked to obesity, while in a study published last September, scientists found a link between another popular food additive and changes in the gut bacteria of mice—artificial sweeteners.