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 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 »
Lactose Intolerance: Symptoms
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: 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 ...more treatments »
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.
Symptoms of lactose intolerance ...more misdiagnosis »
Symptoms of Lactose Intolerance
See full list of 7
symptoms of Lactose Intolerance
Treatments for Lactose Intolerance
- Low-lactose diet
- Lactose-reduced milk
- Milk-free diet
- Dairy-free diet - avoiding all dairy products, not just milk
- Lactase enzyme pills
- more treatments...»
See full list of 9
treatments for Lactose Intolerance
Home Diagnostic Testing
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Wrongly Diagnosed with Lactose Intolerance?
Lactose Intolerance: Related Patient Stories
Lactose Intolerance: Deaths
Read more about Deaths and Lactose Intolerance.
Alternative Treatments for Lactose Intolerance
Alternative treatments or home remedies that have been listed in various sources as possibly beneficial 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)
- more treatments »
Diagnostic Tests for Lactose Intolerance
Read more about tests for Lactose Intolerance
Lactose Intolerance: Complications
Read more about complications of Lactose Intolerance.
Causes of Lactose Intolerance
See full list of 8
causes of Lactose Intolerance
More information about causes of Lactose Intolerance:
Disease Topics Related To Lactose Intolerance
Research the causes of these diseases that are similar to, or related to, Lactose Intolerance:
Lactose Intolerance: Undiagnosed Conditions
Commonly undiagnosed diseases in related medical categories:
Misdiagnosis and Lactose Intolerance
Mild worm infections undiagnosed in children: Human worm infestations, esp. threadworm, can be overlooked in some cases,
because it may cause only mild or even absent symptoms.
Although the most common symptoms are anal...read more »
Chronic digestive conditions often misdiagnosed: When diagnosing chronic symptoms
of the digestive tract, there are a variety of conditions that may be misdiagnosed.
The best known, irritable bowel syndrome, is over-diagnosed,...read more »
Intestinal bacteria disorder may be hidden cause: One of the lesser known causes of diarrhea
is an imbalance of bacterial in the gut, sometimes called intestinal imbalance.
The...read more »
Antibiotics often causes diarrhea: The use of antibiotics are very likely
to cause some level of diarrhea in patients.
The reason is that antibiotics kill off not only "bad" bacteria,
but can also kill the ...read more »
Food poisoning may actually be an infectious disease: Many people who come down
with "stomach symptoms" like diarrhea assume that it's "something I ate" (i...read more »
Mesenteric adenitis misdiagnosed as appendicitis in children: Because appendicitis is one of the
more feared conditions for a child with abdominal pain, it can be...read more »
Blood pressure cuffs misdiagnose hypertension in children: One known misdiagnosis issue
with hyperension, arises in relation to the simple equipment used to test blood pressure.
The "cuff"...read more »
Celiac disease often fails to be diagnosed cause of chronic digestive symptoms: One of the most common chronic digestive
conditions is celiac disease, a...read more »
Children with migraine often misdiagnosed: A migraine often fails to be
correctly diagnosed in pediatric patients.
These patients are not the...read more »
Vitamin B12 deficiency under-diagnosed: The condition of Vitamin B12 deficiency
is a possible misdiagnosis of various conditions, such as multiple sclerosis (see symptoms of...read more »
Chronic digestive diseases hard to diagnose: There is an inherent
difficulty in diagnosing the various types of chronic digestive diseases.
Some of the better known possibilities are peptic ulcer, colon cancer, irritable bowel...read more »
Read more about Misdiagnosis and Lactose Intolerance
Lactose Intolerance: Research Doctors & Specialists
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Hospitals & Clinics: Lactose Intolerance
Research quality ratings and patient safety measures
for medical facilities in specialties related to Lactose Intolerance:
Hospital & Clinic quality ratings »
Choosing the Best Hospital:
More general information, not necessarily in relation to Lactose Intolerance,
on hospital performance and surgical care quality:
Lactose Intolerance: Rare Types
Rare types of diseases and disorders in related medical categories:
Latest Treatments for Lactose Intolerance
Read more about the latest treatments for Lactose Intolerance
Evidence Based Medicine Research for Lactose Intolerance
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Lactose Intolerance: Animations
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Prognosis for Lactose Intolerance
Prognosis for Lactose Intolerance:
Excellent. Well controlled through dietary changes.
More about prognosis of Lactose Intolerance
Research about Lactose Intolerance
Visit our research pages for current research about Lactose Intolerance treatments.
Clinical Trials for Lactose Intolerance
The US based website ClinicalTrials.gov lists information on both federally
and privately supported clinical trials using human volunteers.
Some of the clinical trials listed on ClinicalTrials.gov for Lactose Intolerance include:
Read more about Clinical Trials for Lactose Intolerance
Statistics for Lactose Intolerance
Lactose Intolerance: Broader Related Topics
Types of Lactose Intolerance
Lactose Intolerance Message Boards
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Article Excerpts about Lactose Intolerance
Lactose Intolerance: NIDDK (Excerpt)
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)
Why Does Milk Bother Me: NIDDK (Excerpt)
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)
Food Allergy and Intolerances, NIAID Fact Sheet: NIAID (Excerpt)
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: NWHIC (Excerpt)
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)
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)
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