Lactose Intolerance Causes & Risks

Causes

Lactose intolerance is caused by an inadequate amount of the digestive enzyme lactase. Lactase breaks down the sugar lactose into sugars the bloodstream can more easily absorb. When not fully broken down, lactose ferments in the colon (large intestine) and causes symptoms.

Some people are born with the inability to make the enzyme lactase. Others develop the intolerance over time.

Causes of lactose intolerance include:

Aging (lactase decreases as people age)
Gastroenteritis (or infection in the intestinal tract)
Nontropical and tropical sprue
Cystic fibrosis
Immunoglobulin deficiencies
Ulcerative colitis

Ulcerative Colitis

Risk Factors

A risk factor is something that increases your chance of getting a disease or condition.

Risk factors include:

Race: Black, Asian, or Native American
Ethnicity: Mediterranean or Jewish

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