Everyday chemicals in foods and pesticides may be damaging your gut, study finds
06.12.2025
Common Chemicals May Be Undermining Your Gut Health
Researchers say that dozens of chemicals we encounter in everyday life — from flame retardants to pesticides and plastic additives — may be quietly disturbing the balance of our gut microbiome.
A team from the University of Cambridge has identified 168 substances that can interfere with beneficial gut bacteria. Their findings, published in the journal Nature Microbiology, suggest that the impact of environmental contaminants on gut health is broader than previously recognized.
What the Study Looked At
To map out these risks, scientists tested 1,076 different chemical contaminants on 22 species of gut bacteria. Using the results, they built a machine-learning model to predict which chemicals are more likely to harm the microbiome.
Among the chemicals examined were:
These compounds show up in products such as flame retardants, fungicides, insecticides and plastic-related materials. According to the study, people can be exposed through food, tap water and general environmental contact, although the exact real-world doses and long-term consequences remain uncertain.
The gut microbiome, the researchers noted, is deeply involved in digestion, weight control, immune function and mental health. When these microbial communities are disrupted, it can contribute to a wide range of health issues.
“The Gut Isn’t Just a Digestion Machine”
Lead author Indra Roux said the team was taken aback by the scale of the effects.
They found that chemicals originally designed to target specific organisms — such as insects or fungi — often hit gut microbes as collateral damage. Roux stressed that the gut acts more like a “central command center” for immunity, metabolism and inflammation than a simple food-processing system.
She also pointed out that some industrial chemicals, including certain flame retardants and plasticizers, were long thought to be biologically inert. The new data indicate that they can, in fact, interact with living cells, including gut bacteria.
Co-author Kiran Patil said the goal is to move toward a future where “new chemicals are safe by design.” Now that these interactions have been documented in the lab, he argued, the next step is to gather more real-world exposure data and determine whether similar disruptions occur in people.
Experts Call It a “Wake-Up Call”
South Carolina-based gastroenterologist Dr. Will Bulsiewicz, who was not part of the research, described the study as a “wake-up call.”
He emphasized that the gut microbiome plays a key role in regulating the immune system and inflammation. When the microbes that support the gut barrier are weakened, the intestinal wall can become more permeable, the immune system can become overactivated, and chronic inflammation — linked to many modern diseases — can rise.
Bulsiewicz said there is no need for panic but a strong need for progress. In his view, protecting human health now requires actively protecting the microbes that protect us. That means rethinking how chemicals used in food production, household products and agriculture are developed and tested.
What Consumers Can Do Now
Another expert, Igor Vuyisich, based in Washington and also not involved with the study, said the findings highlight the importance of reducing exposure to substances that can disturb the microbiome.
He suggested people try to:
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Limit unnecessary antibiotic use
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Reduce exposure to pesticides where possible
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Cut back on ultra-processed foods with long ingredient lists
For packaged foods, he recommended reading labels carefully and avoiding ingredients that a previous generation might not recognize, such as benzoate, polysorbate or aspartame. He noted that many conventional supermarket products are “full of additives,” which can make thoughtful shopping more challenging.
Vuyisich stressed that gut health affects nearly every system in the body — from physical and immune health to mood and cognition. Early disruptions in the microbiome may be detectable with specialized tests, including technologies his company works on, though such testing is not yet standard clinical practice.
More Research Is Needed
Scientists who were not involved in the work said the study offers important clues about how environmental chemicals might affect gut bacteria. At the same time, they cautioned that additional research is needed to understand how well these lab-based findings translate to everyday human exposures and disease risk.
The study was funded by the European Research Council and the Medical Research Council UK. Researchers and outside experts agree on one key point: as we learn more about the microbiome, the way we design, regulate and evaluate chemicals in food, farming and household products will likely need to change.
