Lactose intolerance is an inability of the body to digest lactose, a sugar found in milk and other dairy products. Lactose intolerance is often incorrectly referred to as a "milk allergy" or "lactose allergy". Lactose intolerance however, is not an allergy, because it does not involve a reaction of the immune system. Lactose is most correctly described as an adverse reaction, but not an allergy, to food products that contain lactose.
Lactose intolerance is the result of the body's inability to produce enough or any lactase, an enzyme found in the small intestine that digests lactose. This results in such symptoms nausea, bloating, cramping and diarrhea after eating a food or beverage that contains lactose. Common foods and beverages that contain lactose and can cause lactose intolerance include milk, ice cream, soft cheeses, yogurt, sour cream and any food that is made with dairy products.
Symptoms of lactose intolerance vary between individuals depending on such factors as how much lactase an individual makes and the amount of lactose consumed. In rare cases, lactose intolerance can result in serious complications in an infant, such as persistent diarrhea and failure to gain weight. For more details about symptoms and complications, see symptoms of lactose intolerance.
Lactose intolerance can occur in any age group or population. However, people of African, Jewish, Hispanic, Asian, Middle Eastern and Native American descent are at risk for developing lactose intolerance.
Diagnosing lactose intolerance begins with taking a thorough personal and family medical history, including symptoms, and completing a physical examination. Diagnostic testing may include a lactose tolerance test, hydrogen breath test and/or stool acidity test.
A chemistry panel is a blood test that can evaluate if lactose intolerance and diarrhea has lead to the complication of dehydration. An urinanalysis can also help to determine dehydration.
A diagnosis of lactose intolerance and its cause can easily be delayed or missed because lactose intolerance may be intermittent and for other reasons. For information on misdiagnosis, refer to misdiagnosis of lactose intolerance.
There is no cure for lactose intolerance. However, with treatment symptoms can be minimized or eliminated. Treatment includes dietary changes, calcium supplements, and taking a lactose enzyme. For more information on treatment, refer to treatment of lactose intolerance. ...more »
Lactose Intolerance: Lactose intolerance is a difficulty properly digesting lactose (milk sugar) and the various dairy products that contain lactose. It is very common with an estimated 30-50 million Americans affected, especially African Americans, Native Americans, and Mexican Americans. Lactose intolerance causes various digestive symptoms, usually after meals, including cramps, bloating, gas, and diarrhea. ...more »
Symptoms of lactose intolerance can be mild to severe and vary between individuals. Each person with lactose intolerance can have different tolerances for lactose. Symptom severity can differ based on such elements as how much of the enzyme lactase a body produces and the amount of food or beverages that contain lactose that have been consumed.
Symptoms of ...more symptoms »
Lactose intolerance cannot be cured and there is no way to increase the amount of the enzyme lactase that the body produces. Lactase is necessary for the digestion of foods that contain lactose. However, people with lactose intolerance may be able to digest varying amounts of foods and beverages that contain lactose by taking supplements that contain the enzyme ...more treatments »
Diagnosing lactose intolerance and its cause may be delayed or missed because in some cases, lactose intolerance may not be severe enough for a person to seek medical care. In addition, symptoms of lactose can resemble other conditions and diseases, such as irritable bowel syndrome, Crohn's disease, food poisoning, gastroenteritis or celiac disease.
Symptoms of lactose intolerance ...more misdiagnosis »
See full list of 7 symptoms of Lactose Intolerance
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Prognosis for Lactose Intolerance: Excellent. Well controlled through dietary changes.
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Lactose intolerance is the inability to digest significant amounts of lactose, the predominant sugar of milk. This inability results from a shortage of the enzyme lactase, which is normally produced by the cells that line the small intestine. (Source: excerpt from Lactose Intolerance: NIDDK)
Lactose intolerance means that you cannot digest foods with lactose in them. Lactose is the sugar found in milk and foods made with milk. (Source: excerpt from Why Does Milk Bother Me: NIDDK)
Another cause of food intolerance that is often confused with a food allergy is lactase deficiency. This most common food intolerance affects at least one out of ten people. Lactase is an enzyme that is in the lining of the gut. This enzyme degrades lactose, which is in milk. If a person does not have enough lactase, the body cannot digest the lactose in most milk products. Instead, the lactose is used by bacteria, gas is formed, and the person experiences bloating, abdominal pain, and sometimes diarrhea. There are a couple of diagnostic tests in which the patient ingests a specific amount of lactose and then the doctor measures the body's response by analyzing a blood sample. (Source: excerpt from Food Allergy and Intolerances, NIAID Fact Sheet: NIAID)
Lactose intolerance is a condition in which the body is not able to easily digest foods that contain lactose, or the natural sugar that is found in dairy products. Once lactose is in the body, it needs to be broken down into two simple sugars, glucose and galactose, to be absorbed into the blood stream. People who are lactose intolerant have a shortage of lactase enzymes that break down lactose into these sugars. (Source: excerpt from Lactose Intolerance: NWHIC)
The condition resulting from the absence or deficiency of LACTASE in the MUCOSA cells of the GASTROINTESTINAL TRACT, and the inability to break down LACTOSE in milk for ABSORPTION. Bacterial fermentation of the unabsorbed lactose leads to symptoms that range from a mild indigestion (DYSPEPSIA) to severe DIARRHEA. Lactose intolerance may be an inborn error or acquired. - (Source - Diseases Database)
Congenital disorder consisting of an inability to digest milk and milk products; absence or deficiency of lactase results in an inability to hydrolyze lactose - (Source - WordNet 2.1)
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