Lactose is a sugar molecule found naturally in milk. To digest lactose, an enzyme in the body called lactase is needed. Lactose-free milk is still real milk but the lactose is broken down to help the body digest it or, in some cases, the lactose in milk is completely filtered. Some people do not dissolve it smoothly because they may not have enough lactase, so food and beverages are specially processed to make them more suitable for people with mild to moderate lactose intolerance.
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