Lactase

Definition

Enzyme produced by the small intestine which breaks down lactose (milk sugar) into glucose and galactose for absorption.

How it works

Lactase is an enzyme produced by small intestinal epithelial cells, primarily in the jejunum. It catalyzes the hydrolysis of lactose, a disaccharide present in milk and dairy products, into two monosaccharides: glucose and galactose. In some individuals, lactase production decreases after childhood, causing lactose intolerance. Lactose intolerance is not an allergy but a result of the inability to digest milk sugar, leading to uncomfortable digestive symptoms. The persistence of lactase into adulthood is a common genetic adaptation in certain population groups.

Role

Breaking down lactose in milk into glucose and galactose for intestinal absorption.

Examples

• Digestion of cow's milk
• Lactose breakdown in yogurt
• Transformation of fresh cheese

Recommendations

If you are lactose intolerant, consume lactose-free dairy products or plant-based alternatives. Try fermented products (yogurt, aged cheese) whose lactose is already degraded. Gradually, the intestine can adapt to small doses of lactose.

Key takeaway

Lactase enables the digestion of lactose, but its absence causes lactose intolerance

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