See Lactase Lactase
Lactose is the natural sugar in milk and other dairy foods made from milk like yogurt and ice cream that forms when two other sugars, glucose and galactose, join together.
For the body to digest lactose, it uses a natural enzyme called lactase to break lactose down into these two sugars.
With inadequate lactase, there is the inability to absorb lactose properly, which can lead to symptoms of lactose intolerance.
Roughly one in ten U.S. adults reports having lactose intolerance.