Foods that once caused no problems can sometimes become difficult to tolerate, leading to bloating, abdominal pain or other digestive symptoms.

This can be particularly frustrating for people with inflammatory bowel disease (IBD), who may continue experiencing food-related discomfort even when their condition is in remission.

Researchers have identified a possible explanation involving changes in the gut microbiome and immune system. A study published in Gastroenterology suggests that intestinal inflammation may disrupt beneficial bacteria, potentially altering how the body responds to certain foods.

The findings offer new insight into persistent digestive symptoms and could help guide future research into more targeted treatments.

<h3>Why Digestive Symptoms Persist</h3>

Inflammatory bowel disease includes Crohn's disease and ulcerative colitis, two chronic conditions that cause inflammation in the digestive tract.

Although medication can help control inflammation, remission does not always mean that digestive symptoms disappear completely.

According to Alberto Caminero, an associate professor at McMaster University in Canada, up to 70% of people with IBD report symptoms associated with particular foods.

Dairy products and wheat are frequently mentioned as possible triggers, although individual responses vary considerably.

To investigate why these sensitivities develop, Caminero and his colleagues examined whether intestinal inflammation could produce lasting changes in the gut environment.

<h3>How The Research Was Conducted</h3>

The investigation combined laboratory experiments involving mice with observations from 148 adults aged between 18 and 75.

The human participants included people with Crohn's disease, ulcerative colitis and individuals without IBD.

Researchers used two mouse models of intestinal inflammation to examine how changes in the digestive system influenced responses to food proteins.

They found that inflammation increased susceptibility to immune reactions involving components of foods such as wheat and dairy products.

These reactions involved immunoglobulin E (IgE), an antibody associated with allergic responses, and mast cells, which release substances involved in immune signalling.

In the animal experiments, the reactions were largely concentrated in the digestive tract rather than producing widespread symptoms throughout the body.

<h3>The Role Of Gut Bacteria</h3>

A particularly important finding concerned the intestinal microbiome, the complex community of microorganisms that helps support digestion and immune function.

Inflammation was associated with a reduction in certain beneficial bacteria involved in processing dietary components. The researchers investigated whether these microbial changes could influence food-related immune responses.

When gut microorganisms from mice with intestinal inflammation were transferred into healthy mice, the recipient animals became more susceptible to adverse reactions to food.

The team also identified microbiome differences among human participants with IBD who reported food-related symptoms.

However, these observations do not establish that the same mechanism causes food sensitivities in humans.

<h3>What Specialists Say</h3>

Caminero explained that the findings may help clarify why some people begin reacting to foods they previously tolerated without difficulty.

Gastroenterologist Alyssa M. Parian, who was not involved in the study, considered the research relevant to patients who continue experiencing digestive discomfort despite evidence that intestinal inflammation has improved.

She suggested that investigating microbial changes could eventually lead to better ways of understanding these persistent symptoms.

Another independent specialist, Rudolph Bedford, highlighted the potential importance of restoring beneficial microbial functions. However, he cautioned that additional human research would be necessary before translating these findings into clinical treatments.

<h3>What This Means For Patients</h3>

The results raise the possibility that future treatments could focus on restoring specific bacterial functions or modifying abnormal immune responses.

Nevertheless, the research remains preliminary. Much of the evidence comes from animal experiments, and the human component cannot establish a direct cause-and-effect relationship.

People with IBD should discuss persistent food-related symptoms with a healthcare professional before eliminating major food groups. Unnecessary dietary restrictions can increase the risk of nutritional deficiencies.

Keeping a food and symptom diary may help identify patterns and support discussions with a gastroenterologist or dietitian.

The study adds an important piece to the growing understanding of how inflammation, gut microorganisms and immune responses interact. Further research could reveal whether restoring microbial balance can improve food tolerance and digestive health.