You may not think much about the thickening agents in your favorite salad dressing or ketchup, but scientists have just discovered something surprising about them.
A team from the University of British Columbia has found that our gut bacteria can actually digest these agents — something experts didn’t think was possible until now.
These thickening agents are made from modified cellulose, a plant-based material. For years, researchers believed that these large molecules passed through our bodies without being broken down. But new research led by Dr. Deepesh Panwar, a postdoctoral fellow at the Michael Smith Laboratories, shows otherwise.
Published in the Journal of Bacteriology, the study reveals that gut bacteria can digest these cellulose-based food additives. The trick? The bacteria need to be “primed” with natural polysaccharides — long sugar chains found in healthy foods like fruits, vegetables, and grains.
When these natural fibers are present, they switch on special enzymes in the bacteria. These enzymes not only help digest regular fiber but can also break down the artificial cellulose in thickeners.
These cellulose derivatives are used in a wide range of products, from salad dressings to toothpaste. Their complex structure is what makes them useful as thickeners, and it also makes them hard to break down. In fact, in high amounts, they’re used in laxatives. But now we know that with the right kind of diet, our gut bacteria are able to tackle them.
The scientists ran lab experiments and were surprised by what they found. Dr. Panwar says it was the first time anyone had seen gut bacteria use these additives as a sugar source for growth. He explained that previous studies didn’t show this because researchers usually tested the additives by themselves, not alongside natural fibers like you’d find in a real diet.
Dr. Harry Brumer, a chemistry professor who worked on the study, said this finding goes against what most scientists believed. These thickeners weren’t supposed to be digestible. But now we know they aren’t completely inactive in our gut. Instead, they may play a small role in feeding gut bacteria — depending on what else you eat.
The researchers aren’t saying these additives are dangerous. In fact, they’ve been safely used in food for many years. What this study does suggest, though, is that we need to take a closer look at how these ingredients interact with the bacteria in our digestive system.
Next, the team plans to explore how common this ability is among other types of gut bacteria and what this might mean for our nutrition.
So the next time you eat a salad with sweet, thick dressing, remember — your gut bacteria may be doing more work than you thought, helping to break down not only the greens but also the dressing itself.
If you care about gut health, please read studies about a surprising link between gut health and eye disease risk and Gut troubles could signal future Parkinson’s disease.
For more about gut health, please read studies that this stuff in coffee and chocolate may impact gut health and Gut health is linked to anxiety levels.
The study is published in the Journal of Bacteriology.
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