Lactose Intolerance

Lactose intolerance is gastrointestinal upset due to the inability to digest significant quantities of lactose. Lactose is a sugar found in milk and other dairy products.

  • Causes

    Lactose intolerance is caused by a reduction in the digestive enzyme lactase. Lactase breaks down the sugar lactose into sugars that can be more easily absorbed. When not fully broken down, lactose ferments in the colon and causes symptoms.

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    Some people are born unable to make lactase. Others develop the intolerance over time.

  • Definition

    Lactose intolerance is gastrointestinal upset due to the inability to digest significant quantities of lactose. Lactose is a sugar found in milk and other dairy products.

  • Diagnosis

    The doctor will ask about your symptoms and medical history. A physical exam will be done. Your doctor may recommend a trial period of eating no milk or milk products to see if symptoms resolve.

    Your doctor may want to perform tests to help make the diagnosis. These may include:

    • Hydrogen breath test
    • Stool acidity test


    Your doctor may recommend a
    biopsy
    to examine small intestine tissue.

  • Prevention

    There are no current guidelines to prevent lactose intolerance.

  • Risk Factors

    Factors that increase your risk of lactose intolerance include:

    • Black, Asian, or Native American race
    • Jewish ethnicity
    • Family history of lactose intolerance

    • Having certain illnesses or conditions that can damage the intestinal tract such as:

      • Gastroenteritis
      • Celiac disease
      • Cystic fibrosis
      • Crohn's disease
      • Chemotherapy

  • Symptoms

    Symptoms of lactose intolerance generally begin within two hours of consuming milk or other dairy products. The severity of symptoms depends on how much lactase your body produces and how much lactose you eat.

    Lactose intolerance may cause:

    • Cramping
    • Bloating
    • Abdominal rumbling sounds
    • Gas
    • Diarrhea
    • Loose stools

  • Treatment

    Temporary lactose intolerance following an infection usually goes away after the intestine heals.


    Treatment for chronic lactose intolerance focuses on managing symptoms. For most people, removing dietary lactose, especially in children and adolescents, would not be recommended. Milk and milk products provide sources of
    calcium
    and other food elements that are hard to replace. If complete elimination is chosen, then careful replacement of calcium is needed for good health.

    Treatments include: