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Lactose intolerance

Lactose intolerance: Introduction

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: Misdiagnosis

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.

...more misdiagnosis »

Causes of Lactose intolerance:

The following medical conditions are some of the possible causes of Lactose intolerance. There are likely to be other possible causes, so ask your doctor about your symptoms.

» Review Causes of Lactose intolerance: Causes | Symptom Checker »

Common Causes of Lactose intolerance

Lactose intolerance: Symptom Checker

Listed below are some combinations of symptoms associated with Lactose intolerance, as listed in our database. Visit the Symptom Checker, to add and remove symptoms and research your condition.

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Lactose intolerance Treatments

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 lactase. ...Lactose intolerance Treatments

Some of the possible treatments listed in sources for treatment of Lactose intolerance may include:

  • Low-lactose diet
  • Lactose-reduced milk
  • Milk-free diet
  • Dairy-free diet - avoiding all dairy products, not just milk
  • Lactase enzyme pills
  • Lactase enzyme drops
  • High-calcium diet - using foods other than milk.
  • more treatments...»

Review further information on Lactose intolerance Treatments.

Alternative Treatments for Lactose intolerance

Alternative treatments or home remedies that have been listed as possibly helpful for Lactose intolerance may include:

  • Lactase supplement
  • Low-lactose diet
  • Eliminate dietary lactose (including whey, milk byproducts, nonfat dry milk powder, malted milk, buttermilk, dry milk solids)
  • Calcium
  • Vitamin D
  • more treatments »

Stories from Users for Lactose intolerance

Real-life user stories relating to Lactose intolerance:

Lactose intolerance: Comorbid Symptoms

Some of the comorbid or associated medical symptoms for Lactose intolerance may include these symptoms:

Causes of General Symptom Types

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Causes of Similar Symptoms to Lactose intolerance

Research the causes of these symptoms that are similar to, or related to, the symptom Lactose intolerance:

Lactose intolerance: Deaths

Read more about causes and Lactose intolerance deaths.

Misdiagnosis and Lactose intolerance

Vitamin B12 deficiency under-diagnosed: The condition of Vitamin B12 deficiency is a possible misdiagnosis of various conditions, such as multiple more »

Article Excerpts about Lactose intolerance

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)

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)

Lactose intolerance is the inability to digest significant amounts of... (Source: excerpt from Lactose Intolerance: NIDDK)

Lactose intolerance means that you cannot... (Source: excerpt from Why Does Milk Bother Me: NIDDK)

Another cause of food intolerance that is often confused with a food allergy is lactase... (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... (Source: excerpt from Lactose Intolerance: NWHIC)

Definitions of Lactose intolerance:

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)

Detailed list of causes of Lactose intolerance

The list below shows some of the causes of Lactose intolerance mentioned in various sources:

How Common are these Causes of Lactose intolerance?

This information refers to the general prevalence and incidence of these diseases, not to how likely they are to be the actual cause of Lactose intolerance. Of the 9 causes of Lactose intolerance that we have listed, we have the following prevalence/incidence information:

  • 0 causes are "very common" diseases
  • 1 causes are "common" diseases
  • 3 causes are "uncommon" diseases
  • 0 causes are "rare" diseases
  • 0 causes are "very rare" diseases
  • 6 causes have no prevalence information.

Conditions listing medical symptoms: Lactose intolerance:

The following list of conditions have 'Lactose intolerance' or similar listed as a symptom in our database. This computer-generated list may be inaccurate or incomplete. Always seek prompt professional medical advice about the cause of any symptom.

Select from the following alphabetical view of conditions which include a symptom of Lactose intolerance or choose View All.

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Causes of Lactose intolerance Based on Risk Factors

This information shows analysis of the list of causes of Lactose intolerance based on whether certain risk factors apply to the patient:

  • Travel - has the patient travelled recently?

    What are the alternative names for Lactose intolerance:

    Lactase deficiency, Alactasia, hereditary, Disaccharide intolerance type 2, Hypolactasia
    - (Source - Diseases Database)

    Classifications of Lactose intolerance:

    Medical Conditions associated with Lactose intolerance:

    Metabolic symptoms (391 causes)

    Symptoms related to Lactose intolerance:

    Celiac disease, Chronic digestive diseases, Crohn's disease, Gastroenteritis (35 causes), Inflammatory bowel diseases, Intestinal injury, Prematurity, Race

    Medical articles on signs and symptoms:

    Doctor-patient articles related to symptoms and diagnosis:

    These general medical articles may be of interest:

    Evidence Based Medicine Research for Lactose intolerance

    Medical research papers related to Lactose intolerance include:

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    Related medical articles from our Disease Center for Lactose Intolerance:

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