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For people with Down syndrome, family members, caregivers and professionals.

Lactose Intolerance

April 2018 | Brian Chicoine, MD - Medical Director, Adult Down Syndrome Center

People with Down syndrome can experience a variety of gastrointestinal issues. One of them is intolerance to foods containing lactose. Lactose is a sugar found in dairy products like milk and ice cream. While the exact prevalence of lactose intolerance in people with Down syndrome is not known, the condition is something a number of people with Down syndrome do experience. 

Lactose is a two-molecule sugar that is broken into two parts in the intestines by an enzyme called lactase. The two separated molecules can be absorbed through the intestinal wall. If the sugar is not broken down, the molecules cannot be broken down or absorbed. They sit in the intestine and can ferment causing symptoms. Symptoms may include: 

  • Abdominal pain
  • Bloating 
  • Flatulence (gas)
  • Diarrhea

Some individuals with Down syndrome who have a strong tendency towards being constipated do not get diarrhea as a symptom. The constipation they always experience is not overcome by the diarrhea associated with lactose intolerance. In these individuals, the other symptoms may be more prevalent. 

Treatment can include: 

  1. Avoidance of dairy products that cause symptoms.
  2. Eating or drinking food that has been pre-treated to break down lactose. For example, lactase-treated milk, which is available in grocery stores, has been treated with the enzyme lactase to allow for proper absorption.
  3. Taking lactase medications. The enzyme lactase is available in pill and liquid forms and can be taken (preferably) before eating foods containing lactose to avoid symptoms. 

In addition, celiac disease is more common in people with Down syndrome. Celiac disease and lactose intolerance can co-exist. People with Down syndrome treated for celiac disease sometimes have some persistent symptoms. It may be that they also have lactose intolerance and the residual symptoms are from lactose intolerance and not celiac disease. Both conditions need to be addressed for those individuals. 

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Please note: The information on this site is for educational purposes only and is not intended to serve as a substitute for a medical, psychiatric, mental health, or behavioral evaluation, diagnosis, or treatment plan by a qualified professional. We recommend you review the educational material with your health providers regarding the specifics of your health care needs.