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Gastroenterology (GI)

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Lactose Intolerance

Symptoms and Diagnosis | Treatment | For More Information

The inability to absorb lactose is one of the most common forms of food intolerance. Our bodies normally break down lactose, a sugar found in milk and other dairy products, with the help of an enzyme produced in the small intestine called lactase. As we age, many of us lose this enzyme and its digestive properties. In fact, up to 75% of adults around the world will lose lactase and will not be able to properly digest lactose. For these individuals, lactose intolerance can lead to stomach pain and other GI symptoms such as bloating and loose stools.

Ethnic origin has much to do with the prevalence of this condition. For example, lactose intolerance is four times more likely to affect people of Asian and African descent when compared to Caucasians.

Lactose Intolerance Symptoms and Diagnosis

Signs of lactose intolerance can appear as quickly as 30 minutes or several hours after ingesting food or beverages containing lactose. Common lactose intolerance symptoms include:

  • bloating
  • swelling
  • diarrhea
  • abdominal pain
  • gas (flatulence)

Since the inability to process lactose sets off the symptoms of lactose intolerance, the easiest way for your gastroenterologist to diagnose this condition is to have you go on a lactose-free diet for several weeks. If your lactose intolerance symptoms disappear, it is likely you are lactose intolerant. Another option is to try a lactose challenge by ingesting a dairy product such as a glass of milk and seeing if symptoms develop. Your gastroeterologist also might order a hydrogen breath test or a lactose intolerance test.

Treatment for Lactose Intolerance

The most effective treatment for lactose intolerance is to adhere to a lifelong lactose-free diet. Your physician may also recommend over-the-counter lactase enzyme supplements. This is often used in combination with diet modification.

For More Information

For more information on lactose intolerance tests and symptoms or to schedule an appointment with one of our gastroenterologists, please call 847.657.1900.