Symptoms of lactose intolerance can be mild or severe, depending on how much lactase your body makes. Symptoms usually begin 30 minutes to 2 hours after eating or drinking milk or milk products. If you have lactose intolerance, your symptoms may include:
Loose stools or diarrhea. Sometimes the stools are foamy.
Many people think they are lactose-intolerant, because the symptoms of lactose intolerance are very common symptoms. If you feel sick after drinking a glass of milk one time, you probably do not have lactose intolerance. But if you feel sick every time you have milk, ice cream, or another dairy product, you may have lactose intolerance.
Sometimes people who have never had problems with milk or dairy products suddenly have lactose intolerance. This is more common as you get older.
Symptoms of the most common type of lactose intolerance-adult lactose intolerance-often start during the teen or adult years and continue for life. Symptoms of acquired lactose intolerance last as long as the small intestine does not make lactase.
Lactose intolerance is not the same thing as a food allergy to milk. Symptoms of a milk allergy are usually more severe than those from lactose intolerance. People who have a milk allergy cannot eat or drink any milk products. For more information, see the topic Food Allergies.
If you think you might have lactose intolerance, talk it over with your doctor. Your doctor can make sure that your symptoms are caused by lactose intolerance and not by another problem. Other conditions can cause symptoms similar to those of lactose intolerance, including irritable bowel syndrome, inflammatory bowel disease, overuse of laxatives, and problems digesting foods that contain fructose and sorbitol.
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This information is produced and provided by the National
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Institute via the Internet web site at http://
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WebMD Medical Reference from Healthwise
July 21, 2014
This information is not intended to replace the advice of a doctor.
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