The exact cause ofirritable bowel syndrome (IBS)is unknown.
Some of the first signs of IBS include abdominal pain, bloating, diarrhea, and/or constipation.
Researchers think the causes may lie in how the gut and brain communicate.But there are other possibilities.

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Research shows that adverse early life events significantly influence the communication pathways within the brain and the gut.
However, the reasons for this are still poorly understood.
Experts suggest that inflammation leads to malfunctions in the nervous system response.

The spasms are spontaneous contractions of the muscles of the intestines.
This is calledpost-infectious IBS (PI-IBS).
Repeated or Long-Term Antibiotic Use
Antibiotics are known the disrupt the bacteria in the gut.
These changes can include reducing species diversity, altering metabolic activity, and increasing the amount of antibiotic-resistant organisms.
Increased, repeated, and long-term use of antibiotics only amplifies these negative effects on the gut microbiome.
These include having:
What Triggers IBS Symptoms?
For example, some types of carbohydrates are quickly fermented in the large intestine but poorly absorbed.
This leads to symptoms such as abdominal pain, bloating,distension, and gas.
Stressis another common trigger for IBS symptoms.
Stress increases levels of the hormonecortisol, which is linked to a worsening of IBS symptoms.
What Foods May Cause IBS Triggers?
Many different foods can cause symptoms in people with IBS.
Specific food triggers will vary from person to person and can change over time.
Track these symptoms for at least six to eight weeks to see if a pattern develops.
Common triggers for IBS symptoms include certain foods and stress.
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