Got lactase?

Lactase is the enzyme responsible for breaking down lactose, a sugar molecule found in dairy products. When your body doesn't produce enough lactase, lactose intolerance can form, causing gastrointestinal discomfort.

Why are only some people lactose intolerant?

There are three ways a person could be at risk for lactose intolerance.

  1. A mutation in the gene responsible for producing lactase can cause lactose intolerance from birth.
  2. Diseases that destroy the lining of the small intestine, such as celiac or Crohn's disease, can cause a lack of lactase production.
  3. Our bodies naturally decrease lactase production after childhood. This is the most common cause of lactose intolerance, and it affects some ethnic groups more regularly than others.

All of these cause lactase deficiency, which is what it sounds like: the body failing to produce an adequate amount of lactase. However, it is only lactose intolerance when you experience gastrointestinal symptoms.

Who does it affect?

Lactose intolerance can affect anyone. It is more common in adults than children because of the natural drop in lactase that occurs after childhood. It also is more common among some ethnic groups. For example, because Asian and Native American diets traditionally had no dairy, they didn't develop the ability to digest lactose.