What's going on in the colon of someone who has IBS?

The colon, or large intestine, is about five feet long. Muscle movements of the colon move its contents slowly back and forth but mainly toward the rectum. A few times each day, strong muscle contractions move down the colon pushing fecal material. Some of these contractions result in a bowel movement.

Some people with irritable bowel syndrome (IBS) have an abnormality in this muscular action. The colon also appears to be more sensitive and reactive than usual. Otherwise ordinary events (such as eating and distension from gas or other material in the colon) can cause the colon to overreact. Certain medicines and foods, such as chocolate, high-fat foods, milk products or large amounts of alcohol, may trigger IBS attacks. Caffeine can cause loose stools even in some people without the condition. It is particularly problematic for some people with IBS.

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.