Functional tests, hydrogen exhalation tests (lactose, lactulose, fructose)

Hydrogen (H2) exhalation tests are gastroenterological tests that help to make a diagnosis without instrumental intervention, based on the change in the amount of hydrogen in the air exhaled by the patient.
The exhalation tests require the ingestion of a special liquid containing lactose, fructose or lactulose, which triggers a change in the composition of the exhaled air, confirming the presence of the disease. A hydrogen exhalation test can also be used to diagnose lactose intolerance, contaminated small intestine syndrome (SIBO) caused by bacteria in the colon, and fructose malabsorption. The most common way to diagnose lactose intolerance is the H2 breath test, which involves testing the hydrogen content of the air exhaled by the patient at intervals after drinking a lactose-containing drink.
In the case of lactose intolerance, after consuming lactose, the hydrogen content of the exhaled air increases significantly, as the lactose in the intestine produces hydrogen gas, part of which is absorbed into the bloodstream and is expelled through the lungs when exhaled.

Lactose intolerance, also known as lactose sensitivity, is a condition in which the body is unable to digest lactose (milk sugar) in the diet due to a lack of the enzyme that breaks down milk sugar (lactase).

Milk sugar (lactose) is a complex sugar that requires the enzyme lactase, produced in the small intestine, to digest it, breaking down the lactose molecule into simple sugars that the body can use.

Lactose intolerance is not actually a disease but an evolutionary condition, as adult mammals no longer need to digest lactose.
For this reason, the production of the lactose-degrading enzyme in humans also decreases significantly with age following a period of breast feeding, a genetic variation that results in some people still retaining it.

The most common way to diagnose lactose intolerance is the H2 breath test, which involves testing the hydrogen content of the air exhaled by the patient at intervals after drinking a lactose-containing drink.
In the case of lactose intolerance, after consuming lactose, the hydrogen content of the exhaled air increases significantly, as the lactose in the intestine produces hydrogen gas, part of which is absorbed into the bloodstream and is expelled through the lungs when exhaled.

The lactulose hydrogen excretion test is used to detect the presence of abnormally overgrowing bacteria in the small intestine from the large intestine.
This condition is known as contaminated small intestine syndrome (SIBO) and is associated with bloating, abdominal pain, diarrhoea, constipation and early feeling of fullness.
The bacteria in the small intestine break down undigested carbohydrates, resulting in the production of hydrogen and methane gas, which is also measured in the exhaled air.

The fructose hydrogen expulsion test is used to test for fructose (fructose) malabsorption (fructose malabsorption).
This malabsorption causes fructose to enter the large intestine in an undigested form, where it ferments, resulting in increased gas formation.
This causes unpleasant abdominal symptoms (bloating, diarrhoea cramps).

• Stop taking antibiotics and probiotics 4 weeks before the test.
• After endoscopic procedures and surgeries, at least 4 weeks should pass before the H2 expiration test.
• A day before the test, avoid eating fruit and vegetables, peanuts and oilseeds.
• Do not drink milk or dairy products the day before the test.
• Do not drink alcohol or carbonated drinks a day before the test.
• No smoking on the day of the test.
• On the day of the test, arrive on an empty stomach and bring any medication you are taking with you.
• Do not use toothpaste, mouthwash, lipstick, face cream, chewing gum or sweets on the day of the test.
• Use a clean, new toothbrush to clean your teeth and tongue.

– 1 drop of blood from the fingertip; – then 75 grams of glucose (glucosum anhydricum) is added; – then blood is taken every 30 minutes.
For both blood sugar and starch loading, blood glucose is checked.

Fructose is a simple sugar (monosaccharide) found in large quantities mainly in fruits, vegetables and honey.
In the case of fructose malabsorption, fructose is not absorbed in the small intestine, but passes unchanged to the large intestine, where it is broken down by the intestinal bacterial flora into bloating gases (hydrogen, methane) and laxative fatty acids.
It has a high prevalence of 35% in the European population.
A fructose malabsorption disorder may be indicated by bloating, diarrhoea, abdominal pain or other digestive problems after eating sugary foods, fruits or vegetables.

Hydrogen Breath Test A HYDROGEN BREATH TEST FOLLOW-UP: An exhalation test to detect the sensitivity of a bacterial degradation test based on the formation of gas released during bacterial degradation – the so-called hydrogen exhalation test.
The test consists of measuring the increase in hydrogen concentration in the exhaled air after ingestion of a fructose solution.

• The test requires an empty stomach, no food or drink – not even water!
• NO brushing, mouthwash, smoking, chewing gum
• Avoid fruit, juices, bloating foods and drinks (pulses, oilseeds, carbonated drinks), coffee and alcoholic drinks the day before the test
• The duration of the examination is 2 hours, during which time you will need to stay in the surgery.
  After consuming the fructose solution, you will be asked to blow into a hydrogen level meter every 15/30 minutes.
  Treatment of fructose intolerance
• The most effective form of treatment for fructose intolerance is to reduce, and if necessary eliminate, the consumption of foods and drinks containing fructose.
• An enzyme that helps fructose to break down more quickly is now available domestically.
• Fructose is widely used in the food and pharmaceutical industries, so care should be taken when selecting industrially processed foods and medicines.
• An individualised diet should be followed, with the help of a dietician if necessary.

• low fructose fruits: strawberries, raspberries, blackberries, lemons, grapefruit, kiwi fruit
• glucose, erythritol, stevia, xylitol
• rice syrup

Xylose isomerase enzyme (Xylosolv, Fructaid capsules): converts fructose into glucose in the body.
Only for use in fructose malabsorption!
Note, dietary maintenance is the basis of treatment, similar to lactose and histamine sensitivity.
Enzyme supplementation is only recommended as a supplement.
So if you are eating in a place where free food is not available e.g. travel, restaurant, bakery etc.
The Hydrogen Breath Test is performed with the Gastro+ Gastrolyzer (Bedfont) – a functional, non-invasive provocation laboratory test.
It can be used to test for lactose intolerance and fructose malabsorption, as well as SIBO (Small Intestinal Bacterial Overgrowth), a contaminated small intestine syndrome.