Eating More Ultra-Processed Foods May Raise Crohn’s Disease Risk

Ultra-processed foods have sadly become the backbone of modern eating. They’re convenient, shelf-stable, and engineered to hit all the right pleasure points. I reach for them too—on travel days, between deadlines, or when “real food” feels like one more thing on an already long list.

But a growing body of research suggests these foods may be doing more than saving us time. They may be changing the gut in ways that matter, especially when it comes to Crohn’s disease.

Globally, nearly five million people now live with inflammatory bowel disease (IBD), and rates continue to rise fastest in countries where ultra-processed foods dominate the diet. Genetics can’t explain that kind of shift. So researchers have started asking a different question. 

What in our environment is pushing the gut toward chronic inflammation?

A new narrative review1 published in Nutrients pulled together more than a decade of research examining how ultra-processed foods relate to Crohn’s disease and ulcerative colitis. Instead of focusing on a single study, researchers analyzed population data, mechanistic experiments, and dietary interventions to see whether a consistent pattern emerged.

What they found was hard to ignore.

Across large observational studies, people who ate more ultra-processed foods had a higher risk of developing Crohn’s disease. That link was far weaker for ulcerative colitis, suggesting Crohn’s may be especially sensitive to dietary exposures.

Ultra-processed foods aren’t just “processed” in the everyday sense. They’re industrial formulations made from refined ingredients and additives designed to enhance flavor, texture, and shelf life. Emulsifiers, artificial sweeteners, thickeners, and colorants are common and increasingly under scrutiny.

Mechanistic studies offer clues as to why. Some emulsifiers appear to thin the gut’s protective mucus layer, making it easier for bacteria to come into direct contact with intestinal tissue. Others shift the gut microbiome, reducing beneficial microbes while encouraging more inflammatory ones.

There’s also evidence that certain additives can increase intestinal permeability, often referred to as “leaky gut,” which allows bacterial fragments to cross into the bloodstream and activate immune responses. Over time, this low-grade immune activation may help set the stage for chronic inflammation seen in Crohn’s disease.

To be clear, this research doesn’t prove that ultra-processed foods directly cause Crohn’s disease. Most of the evidence is observational. But when population data lines up with biological mechanisms, and with clinical outcomes, the signal gets harder to ignore.

For people already living with IBD, higher intake of ultra-processed foods has been associated with greater disease activity and higher relapse risk. On the flip side, dietary approaches that dramatically reduce ultra-processed foods, like the Crohn’s Disease Exclusion Diet, have been shown to induce remission, particularly in children.

Even if you don’t have IBD, the implications still matter. The same gut changes linked to Crohn’s disease—microbiome disruption, barrier breakdown, chronic inflammation—are also tied to metabolic disease, immune dysfunction, and mental health conditions.

This isn’t about demonizing food or aiming for perfection. Ultra-processed foods exist on a spectrum, and convenience is sometimes necessary. But the research supports being more aware of how often these foods make up the bulk of our diet.

Ultra-processed foods aren’t just empty calories; they may actively shape the gut in ways that increase vulnerability to disease, particularly Crohn’s.

While scientists are still untangling cause and effect, one message is becoming clearer: the more our diets move away from foods in their natural form, the more our gut seems to pay the price.