compound
Lactose
Lactose is the disaccharide sugar naturally present in mammalian milk.
Educational draft · Human scientific and editorial review pending. About review status
It is made from glucose and galactose and is broken down by lactase in the small intestine in people who produce enough of that enzyme.
How it works
Milk sugar
Lactose is a disaccharide, so digestion separates it into monosaccharides before absorption. Its amount and tolerance depend on the food and on lactase activity; those are distinct questions from lactose’s chemical identity.
Related topics
Lactose is digested to release Glucose
Lactose digestion releases glucose and galactose as separate monosaccharides.
Evidence: Established · Source checked 2026-09-05 · Sources: European Food Safety Authority: Scientific Opinion on Dietary Reference Values for carbohydrates and dietary fibre
Worth knowing
It is not sucrose. Lactose contains glucose and galactose, whereas sucrose contains glucose and fructose.
A closer look
Digestion depends on lactase
Lactose content and lactose digestion are separate measurements: lactase activity in the small intestine determines how much is broken down before absorption.
References
Source-checked local draft.
Human editorial review pending.