Lactose facts for kids

This diagram shows what lactose looks like.

Lactose is a type of sugar found naturally in milk and many dairy products. It's often called "milk sugar." It's made up of two smaller sugar molecules joined together: glucose and galactose. About 2% to 8% of the solid parts of milk are lactose. The word "lactose" comes from the Latin word for milk, with the common ending "-ose" that is used for many sugars.

How Our Bodies Use Lactose

When baby mammals, including humans, drink milk, their bodies need to break down the lactose. To do this, they use a special helper molecule called an enzyme. This enzyme is named lactase.

Lactase works like tiny scissors. It cuts the lactose molecule into its two smaller parts: glucose and galactose. Once lactose is broken down, these smaller sugar molecules can be easily absorbed by the body. They then provide energy for growth and daily activities.

Images for kids

• 

  This image shows the molecular structure of α-lactose, as seen with special X-ray equipment.

• 

  Here you can see lactose crystals, viewed under a microscope with polarized light.

See also

In Spanish: Lactosa para niños