Lactose intolerance
Conditions
Allergy & immunology
What is lactose intolerance? Lactose intolerance is a food intolerance that occurs after the ingestion of lactose. Lactose is a sugar that’s found in milk and milk products. If you are lactose intolerant, your body is unable to break down this sugar. What causes lactose intolerance? To digest lactose, the body needs an enzyme called lactase. Lactose int