Scientists have found that many man-made chemicals we come into contact with every day could be harming the healthy bacteria in our gut.
These gut bacteria are important for digestion, immunity, and even mental health.
The new research, done at the University of Cambridge and published in Nature Microbiology, tested more than 1,000 chemicals in a laboratory and found that 168 of them were toxic to gut bacteria.
These harmful chemicals included common pesticides sprayed on food crops, as well as industrial chemicals used in things like flame retardants and plastics. Most of these chemicals were not previously believed to have any effect on bacteria, but this study shows they can stop gut bacteria from growing or functioning properly.
The researchers tested the effects of these chemicals on 22 different types of gut bacteria in the lab. They found that the bacteria sometimes change their behavior to resist the chemicals, but this can also make them resistant to antibiotics like ciprofloxacin. If this happens inside the human gut, it could make infections much harder to treat.
The gut microbiome—the community of bacteria living in our intestines—contains thousands of different types of bacteria. These bacteria help keep us healthy, but when their balance is disturbed, it can lead to problems like obesity, digestive issues, and a weaker immune system.
Right now, safety tests for new chemicals do not usually check how they affect gut bacteria. Chemicals are designed to work on specific things—like killing insects or fungi—but they may still harm bacteria in our gut. This study changes that thinking.
To help prevent this problem in the future, the scientists built a computer model using machine learning. It can now predict whether a new chemical might be harmful to gut bacteria. This could help create safer chemicals that are “safe by design”—in other words, designed to avoid harming gut bacteria from the start.
Dr. Indra Roux, who led the study, said the team was surprised by how many chemicals affected gut bacteria. Even industrial chemicals, like flame retardants and plasticizers, which were not believed to affect any living organisms, had strong effects on the bacteria.
Professor Kiran Patil, another lead researcher, said this study is a big step forward. With the new data, scientists can now predict how new chemicals will affect gut bacteria and work toward safer alternatives.
Dr. Stephan Kamrad, who also worked on the study, emphasized that safety checks for chemicals should start including how these chemicals might affect gut bacteria. Right now, we don’t know exactly how much of these chemicals reach our gut, but it’s likely that exposure through food and water is common.
To reduce your risk, the scientists recommend simple steps like washing fruits and vegetables before eating them and avoiding pesticides in home gardens. In the future, more studies will be needed to monitor how these chemicals affect people in real-life situations.
If you care about gut health, please read studies about how probiotics can protect gut health, and Mycoprotein in diet may reduce risk of bowel cancer and improve gut health.
For more health information, please see recent studies about how food additives could affect gut health, and the best foods for gut health.
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