Testing for lactose intolerance is a genetic DNA test that detects the gene polymorphism responsible for lactose intolerance, a pathological condition that affects 30% to 60% of the Greek population. Proper diagnosis of lactose intolerance enables effective treatment of indigestion and malabsorption of lactose, effectively helping to eliminate chronic symptoms such as bloating, gas, diarrhea, and abdominal pain. A simple blood test is all that is required for genetic testing for lactose intolerance.
Lactose intolerance is one of the most common gastrointestinal disorders affecting millions of people worldwide. It is due to a deficiency of an enzyme (lactase) in the intestine, either genetically determined (primary deficiency) or resulting from small bowel diseases (secondary deficiency). Without enough lactase, the digestive system cannot break down and absorb lactose, the basic sugar of milk and dairy products. Subsequently, the unabsorbed lactose is fermented by the bacteria in the large intestine, causing the release of gases (mainly hydrogen and methane).
Symptoms of lactose intolerance include:
- Bloating, feeling full, or swelling of the abdomen
- Abdominal pain and cramps
- Diarrhea
- Gas
- Nausea
Due to this intestinal absorption disorder, lactose intolerance can also cause a deficiency of essential nutrients (vitamins and trace elements), which weakens the digestive system and makes it more prone to infections and inflammation.
Value of Lactose Intolerance testing
When lactose intolerance is diagnosed correctly, appropriate dietary manipulations can quickly treat the patient. However, a misdiagnosis often occurs because symptoms often overlap with those of other pathological conditions. Studies show that up to 70% of patients with lactose intolerance do not relate their symptoms to lactose intake.
Milk and dairy products are considered an essential source of nutrients for children, pregnant women, nursing mothers, and the elderly. Lactose intolerance testing is essential for these people to avoid the unnecessary elimination of dairy products from their diet.
Advantages of Lactose Intolerance Genetic Testing
- It is a very sensitive and specific test for detecting lactose intolerance
- It is not affected by temporary enzyme deficiency due to small bowel diseases (secondary insufficiency); therefore, you will be able to know if you only need to follow a lactose-free diet temporarily or have to follow a life-long lactose-free diet.
- A simple blood sample is all that is required, which can also be done at home (fingerprinting)
- It does not require taking lactose solutions, which can increase symptoms of intolerance in the patient
- It does not require consecutive blood sampling, such as the lactose tolerance test
- A 5-minute visit to the lab is all that is required to take a blood sample, unlike, for example, hydrogen breath tests, which require a 2-hour or more stay in the lab.
Who should be tested for lactose intolerance?
Lactose intolerance testing is recommended for all patients with:
- Irritable Bowel Syndrome (IBS)
- Inflammatory Bowel Disease (IBD)
- Chronic diarrhea and unexplained bloating
- Malnutrition and chronic alcohol use
- Radiation therapies
With the reliable diagnosis provided by molecular testing for lactose intolerance, lactose malabsorption, and all its symptoms, dietary means, lifestyle changes, or dietary supplements can significantly mitigate or eliminate them.
Additional information
Lactose intolerance (adult-type hypolactasia) is the inability of some individuals to digest and absorb lactose (milk sugar), resulting in various gastrointestinal symptoms when consuming milk or milk-containing products. For lactose to be absorbed by the intestine, it should be first broken down into glucose and galactose. The enzyme that converts lactose into glucose and galactose is called lactase and is found on the surface of cells that cover the small intestine. Lactose intolerance is due to the reduced or complete absence of lactase activity, which prevents lactose breakdown (lactase deficiency or hypolactasia).
Usually, lactose intolerance is diagnosed by swallowing pure lactose and measuring exhaled hydrogen. Unfortunately, this test lasts several hours and results in severe and annoying abdominal symptoms in patients with lactose intolerance.
The genetic cause of lactose intolerance has recently been discovered. At position -13910, before the lactase gene (LCT), a polymorphism determines the amount of lactase produced. Testing for the LCT genotype can determine the genetic predisposition for lactose intolerance.
Indications for molecular screening of lactose intolerance include symptoms of lactose intolerance, such as abdominal pain, diarrhea, and flatulence (excessive gas production and bloating) after consuming milk or dairy products.
The most effective means of treating lactose intolerance is reducing the amount of lactose in the diet. Fortunately, most people with lactose intolerance can tolerate small or moderate amounts of lactose. Removing the most critical milk-containing products is often enough to alleviate intolerance symptoms sufficiently. However, dietary restrictions have become more severe for people who are intolerant to even small amounts of lactose, and any milk-containing product should be avoided.
