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    Irritable Bowel Syndrome

    ir·ri·ta·ble bow·el syn·drome — IR-ih-tuh-bul BOW-ul SIN-drome

    Definition

    Irritable bowel syndrome (IBS) is a common disorder affecting the large intestine that causes recurring abdominal pain, bloating, gas, and changes in bowel habits — either diarrhea (IBS-D), constipation (IBS-C), or alternating between both (IBS-M). Unlike inflammatory bowel diseases such as Crohn's disease, IBS does not cause visible damage to the intestinal tissue or increase the risk of colorectal cancer.

    IBS is classified as a functional gastrointestinal disorder, meaning the digestive system looks structurally normal but doesn't function properly. The exact cause is not fully understood, but it appears to involve a combination of gut-brain communication problems, visceral hypersensitivity (nerves in the gut being overly sensitive), altered gut motility, changes in the gut microbiome, and psychological factors like stress and anxiety.

    IBS affects an estimated 10-15% of the global population and is twice as common in women as in men. It typically develops before age 50 and is a chronic condition that is managed rather than cured. While IBS is not dangerous, it can significantly impact quality of life and is one of the leading causes of missed work and school worldwide.

    Also Known As

    IBSSpastic colonNervous stomach

    Key Facts

    • •IBS affects 10-15% of the global population but only about half of those affected seek medical care.
    • •Diagnosis is based on symptom criteria (the Rome IV criteria) after ruling out other conditions.
    • •The low-FODMAP diet — which restricts certain fermentable carbohydrates — provides symptom relief for approximately 70% of IBS patients.
    • •Stress and anxiety are major IBS triggers due to the strong gut-brain connection.
    • •IBS does not increase the risk of colorectal cancer or cause permanent intestinal damage.
    • •New treatments targeting the gut-brain axis, including gut-directed hypnotherapy, have shown promising results.

    How It Relates To Your Health

    If you experience chronic digestive symptoms like recurring abdominal pain associated with bowel changes, IBS may be the explanation. Getting a proper diagnosis is important because it rules out more serious conditions and opens the door to effective management strategies. Many people with IBS suffer for years without seeking help, either because they're embarrassed about their symptoms or assume nothing can be done.

    The low-FODMAP diet, developed by researchers at Monash University, has been a game-changer for IBS management. Working with a registered dietitian experienced in the low-FODMAP approach is the most effective way to identify your personal trigger foods while maintaining a nutritionally complete diet.

    Sources

    1. Irritable Bowel Syndrome (IBS) — National Institute of Diabetes and Digestive and Kidney Diseases (NIH)
    2. Irritable bowel syndrome — Mayo Clinic
    3. IBS Fact Sheet — World Gastroenterology Organisation

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