IBS and Cancer: Is There a Connection?

worried woman in doctor's office
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If you have been experiencing bouts of severe abdominal pain due to irritable bowel syndrome, it is not uncommon that your mind will wander to thoughts of cancer. How else to understand the experience of such disabling pain? In this overview, we will take a look at what is known about any possible relationship between IBS and cancer so as to help to put your mind at ease.

How Do You Know Your IBS Isn't Cancer?

Many people who have IBS worry that their symptoms are actually caused by colon cancer that their doctors have missed.

Research has consistently supported the notion that doctors can make a fairly confident diagnosis of IBS if your symptoms meet the Rome III diagnostic criteria for IBS and if you are not experiencing any "red-flag" digestive symptoms.

One major distinction between IBS and cancer, is that IBS symptoms tend to wax and wane. Cancer symptoms, on the other hand, tend to be persistant and to worsen over time.

Shared Symptoms

The following are some symptoms that are shared by both IBS and colon cancer:

Colon Cancer Symptoms

The following are symptoms that are seen with cancer that are not typically seen with IBS:

  • Anemia
  • Extreme fatigue
  • Jaundice
  • Loss of appetite, also not explained by food avoidance for fear of setting off IBS symptoms
  • Nausea or vomiting
  • Weight loss more than might be explained by eating less to avoid IBS symptoms

    Blood in the stool can certainly be a sign of colon cancer, but it can also be a result of a hemorrhoid, particularly if the blood is bright red. Any sign of blood in or on your stool should be brought to the attention of your physician.

    Click here to learn more about the signs of colon cancer...

    IBS and Colon Cancer Risk

    Another understandable concern about the relationship between IBS and cancer is the fear that having IBS may raise your risk for cancer.

    Unfortunately, research on the subject has been far from clear-cut!

    Some studies have found that people who have IBS are at greater risk for the development of colon cancer, while other studies have found the exact opposite. One study even found a decreased risk!

    Some researchers have found that any increased risk happens within a short time after diagnosis, but levels out to normal risk over time. They attribute this finding to confusion about diagnosis shortly after diagnosis as IBS and colon cancer share many of the same symptoms.

    The Bottom Line

    If your doctor has diagnosed you as having IBS and you have none of the warning signs of cancer, you can put your immediate fears to rest. To keep your cancer risk as low as possible for the future you can:

    1. Follow your doctor's recommendations as to how often to undergo screening

    2. Eat plenty of vegetables and fruit

    3. Maintain a healthy weight

    4. Exercise regularly

    5. Avoid excess alchohol

    Click here to learn more about how to prevent colon cancer...


    Canavan, C., Card, T. & West, J. "The Incidence of Other Gastroenterological Disease following Diagnosis of Irritable Bowel Syndrome in the UK: A Cohort Study" PLoS One 2014 9:e106478.

    Chang, H., et. al. "Irritable bowel syndrome and the incidence of colorectal neoplasia: a prospective cohort study with community-based screened population in Taiwan" British Journal of Cancer 2015 Jan 6; 112:171–176.

    Hsiao, C., et. al. "Association between irritable bowel syndrome and colorectal cancer: a nationwide population-based study." European Journal of Internal Medicine 2014 25:82-6.

    Nørgaard, M., et. al. "Irritable bowel syndrome and risk of colorectal cancer: a Danish nationwide cohort study" British Journal of Cancer 2011 104: 1202–1206.

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