Lactose Intolerance

Also known as: lactose malabsorption.

What is lactose intolerance?

Lactose is a sugar found in milk and milk products. In order to digest and absorb lactose one needs an enzyme called lactase (found in the cells of the small intestine) to break the sugar down into a form (glucose and galactose) that can be absorbed.

Without this enzyme, lactose cannot be absorbed and the condition is known as lactose intolerance because it causes children to have uncomfortable gut symptoms. Some populations are more affected than others (African-American, Mexican/Hispanic -American and others).

What causes lactose intolerance?

There are a number of reasons for lactase deficiency. In a rare form it can be a congenital and inherited from parents where the baby from birth produces little (or no) lactase; often it's found in infants born prematurely or as a result of injury to the small intestine.

Frequently lactase deficiency results from a gradual decrease in enzyme over time starting around 2 years of age (this type of deficiency may also be inherited).

What are the symptoms of lactose intolerance?

Common symptoms (mild to severe) that occur 30 minutes to 2 hours after drinking milk or eating milk products include:

What are lactose intolerance care options?

The best treatment for lactose intolerance is avoiding or limiting the amount of lactose eaten. You can choose lactose-free products or add a product (lactase) to dairy products to break down the lactose before consuming it.

Reviewed by: Jack Wolfsdorf, MD, FAAP

This page was last updated on: May 22, 2023 10:59 AM

Pediatric Gastroenterology

The Division of Pediatric Gastroenterology at Nicklaus Children’s Hospital is dedicated to the treatment of a wide variety of gastrointestinal problems in infants, children and adolescents with a multidisciplinary approach.

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