A new research review suggests that eating more ultra-processed foods may be linked to a higher risk of developing Crohn’s disease. The review, published in the journal Nutrients, examined over a decade of studies on the relationship between these foods and inflammatory bowel disease (IBD).
Nearly five million people worldwide live with IBD, and rates are rising fastest in countries where ultra-processed foods are common. Researchers analyzed population data, experiments, and dietary interventions to see if a pattern emerged. They found that people who ate more ultra-processed foods had a higher risk of Crohn’s disease. The link was much weaker for ulcerative colitis, another form of IBD.
Ultra-processed foods are industrial formulations made with refined ingredients and additives such as emulsifiers, artificial sweeteners, thickeners, and colorants. These additives are under increasing scrutiny. Mechanistic studies suggest that some emulsifiers may thin the protective mucus layer in the gut, making it easier for bacteria to contact intestinal tissue. Other additives may shift the gut microbiome, reducing beneficial microbes and encouraging inflammatory ones. Some evidence also indicates that certain additives can increase intestinal permeability, often called “leaky gut,” allowing bacterial fragments to enter the bloodstream and activate immune responses.
This research does not prove that ultra-processed foods directly cause Crohn’s disease. Most of the evidence is observational. However, the combination of population data, biological mechanisms, and clinical outcomes strengthens the link. For people already living with IBD, higher intake of ultra-processed foods has been associated with greater disease activity and higher relapse risk. Dietary approaches that reduce ultra-processed foods, such as the Crohn’s Disease Exclusion Diet, have been shown to induce remission, especially in children.
The gut changes linked to Crohn’s disease, including microbiome disruption, barrier breakdown, and chronic inflammation, are also tied to metabolic disease, immune dysfunction, and mental health conditions. This means the findings have implications for people without IBD as well. The review highlights that the structure of the food itself, not just its calorie, fat, or carbohydrate content, may be a key factor.
Researchers suggest that centering meals around whole or minimally processed foods may be a practical way to support gut health. Paying attention to ingredient lists, especially long strings of additives, and building a small rotation of simple meals at home are also recommended. For those with digestive symptoms, working with a practitioner who understands gut health may be helpful.
The takeaway from this research is that ultra-processed foods may actively shape the gut in ways that increase vulnerability to disease, particularly Crohn’s. While scientists are still working to understand cause and effect, the message is becoming clearer: diets that move away from foods in their natural form may come with a gut health cost.
