Lactose Intolerance in Children

What is lactose intolerance in children?

Lactose intolerance is when the body can’t easily break down or digest lactose. Lactose is a sugar found in milk and milk products.

If your child is lactose intolerant, he or she may have unpleasant symptoms after eating or drinking milk products. These symptoms include bloating, diarrhea, and gas.

Lactose intolerance is different from having a food allergy to milk.

What causes lactose intolerance in a child?

Lactose intolerance happens when the small intestine doesn’t make enough of a digestive juice, or enzyme, called lactase. Without enough lactase, the body can’t break down or digest lactose.

Lactose intolerance can happen to both children and adults. Some common causes include:

  • Digestive diseases or infection
  • Injury to the small intestine
  • Family history of lactose intolerance. In these cases, over time the body may make less of the lactase enzyme. Symptoms may occur during the teen or adult years.
  • A baby being born too early, also called a premature baby. This type of lactose intolerance is often a short-term problem that goes away.

In very rare cases, some newborns can’t make any lactase from birth.

Which children are at risk for lactose intolerance?

Lactose intolerance can happen to anyone. But your child is more at risk for lactose intolerance if he or she:

  • Is a baby who was born too early, also called a premature baby. This type of lactose intolerance is often a short-term problem that goes away.
  • Is African American, Jewish, Mexican American, American Indian, or Asian American
  • Has a family history of lactose intolerance. Symptoms may occur during the teen or adult years.

What are the symptoms of lactose intolerance in a child?

Symptoms often begin to appear in white children after age 5. They appear in African-American children as young as 2 years old.

Symptoms begin about 30 minutes to 2 hours after having foods or drinks containing lactose. Each child’s symptoms may vary. Symptoms may include:

  • Upset stomach or nausea
  • Cramps
  • Bloating
  • Belly (abdominal) pain
  • Gas
  • Loose stool or diarrhea
  • Vomiting, happens more often to teens

How severe your child’s symptoms are will depend on how much lactose he or she has had. It will also depend on how much lactase your child’s body makes.

The symptoms of lactose intolerance may look like other health conditions. Always see your child’s healthcare provider for a diagnosis.

How is lactose intolerance diagnosed in a child?

Your child’s healthcare provider will give your child a physical exam and take a health history.

Your child may need to be tested. The most common tests used to check how lactose is absorbed in the digestive system include:

  • Lactose tolerance test. This test checks how lactose is absorbed by your child’s digestive system. After fasting, your child drinks a liquid that has lactose. The loose stools are then tested for lactose for the next 24 hours.
  • Hydrogen breath test. Your child drinks a liquid that has a lot of lactose. The breath is then checked at regular times to measure the amount of hydrogen. High levels of hydrogen mean your child is lactose intolerant.
  • Stool acidity test. This test is used for babies and young children. It checks how much acid is in the stool. If your child is not digesting lactose, the stool will have lactic acid, glucose, and other fatty acids.