A new study has found that many everyday chemicals can harm the good bacteria living in your gut.
These bacteria are important for keeping your body healthy, but researchers have discovered that 168 different human-made substances can stop these microbes from growing properly.
Many of these chemicals are found in food, drinking water, and the environment, but until now, they were not believed to affect gut bacteria.
The study was done by scientists at the University of Cambridge. They tested over 1,000 different chemicals to see how they affected 22 common types of gut bacteria in a lab setting. These chemicals included pesticides like herbicides and insecticides used on crops, and industrial chemicals found in plastics and flame retardants.
Our gut is home to thousands of different kinds of bacteria that help with digestion, the immune system, mental health, and more. If something upsets the balance of these microbes, it can lead to problems with weight, mood, inflammation, and disease.
Unfortunately, most safety tests for chemicals don’t check how these substances might affect gut bacteria. That’s because the chemicals were designed to work on other things—like killing bugs—not on humans or the bacteria living inside them.
Surprisingly, many of the tested chemicals had strong effects on gut bacteria. The researchers were especially concerned to find that some of these bacteria developed resistance to antibiotics such as ciprofloxacin after being exposed to certain pollutants. If this happens inside the human body, it could make some infections harder to treat.
To help predict which chemicals might be harmful in the future, the research team built a computer program using artificial intelligence. This tool uses what the scientists learned from the lab experiments to guess whether a new chemical could hurt gut bacteria. The goal is to make it easier to design safer chemicals from the beginning.
The results of the study, along with the AI tool, were published in the journal Nature Microbiology. Dr. Indra Roux, the lead researcher, said that many chemicals thought to be safe turned out to have unexpected effects on gut microbes.
He explained that even industrial substances, like those used in flame retardants and plastic products, can disrupt the microbiome.
Professor Kiran Patil, a senior researcher on the project, said the most exciting part of the study is that it gives scientists a way to test new chemicals before they are widely used. That way, we can aim for a future where products are safe for both people and the helpful microbes in their bodies.
Dr. Stephan Kamrad, another researcher involved in the work, emphasized that gut safety should be part of testing any new chemical. Since these substances can get into our bodies through food and water, it’s important to know how they affect gut health.
However, the team also pointed out that more work is needed. Right now, we don’t know how much of these chemicals actually reach the gut in real life. Future studies will need to track how much people are exposed to these substances on a daily basis.
Until more is known, the researchers suggest simple steps to reduce risk. Washing fruits and vegetables before eating and avoiding pesticides in your garden can help limit your contact with harmful chemicals.
In summary, this study shows that many everyday chemicals may be quietly harming the helpful bacteria in your gut. With better research and smarter chemical design, scientists hope to protect gut health while still allowing useful products to be made and used.
For more information about gut health, please see recent studies about the crucial link between diet, gut health, and the immune system and results showing that Low-gluten, high-fiber diets boost gut health and weight loss.
For more information about gut health, please see recent studies about Navigating inflammatory bowel disease (IBD) with diet and results showing that Mycoprotein in diet may reduce risk of bowel cancer and improve gut health.
The study is published in Nature Microbiology.
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