Lactose intolerance


People with lactose intolerance do not tolerate many dairy products. Because they lack an enzyme that is needed for the utilization of lactose. The most common symptoms of lactose intolerance are flatulence, abdominal cramping and diarrhea. But lactose intolerance can also be felt outside the gastrointestinal tract. Read here, which triggers lactose intolerance, how to identify food intolerance and what to do about it.

ICD codes for this disease: ICD codes are internationally valid medical diagnosis codes. They are found e.g. in medical reports or on incapacity certificates. E73

If lactose intolerance does not apply to milk and dairy products, it is important to ensure adequate calcium intake to prevent osteoporosis.

Dr. med. Mira SeidelArticle overviewLactose intolerance
  • Lactose intolerance: short overview
  • Causes and triggers
  • symptoms
  • diagnosis
  • treatment
  • Disease course and prognosis
  • frequency

Lactose intolerance: short overview

  • Causes: Deficiency of the enzyme lactase, bacteria produce gases and acids in the colon
  • symptoms: Abdominal pain, diarrhea, abdominal distension, intestinal wind, bloating, nausea, nonspecific symptoms such as headache
  • Diagnosis: H2 breath test, diet / exposure test, symptoms alone provide insufficient evidence
  • Treatment: Adaptation of diet, abandonment of dairy products, lactase tablets
  • Forecast: no illness, not dangerous, but limits quality of life
What happens with a lactose intolerance? A raspberry ice cream with cream does not have any consequences for everyone. As with a lactose intolerance abdominal pain and Co. arise, you learn in the video. A raspberry ice cream with cream does not remain for everyone without consequences. As in the case of a lactose intolerance stomach ache and co. Arise, you will learn in Video.Zum Inhaltsverzeichnis

Lactose intolerance: causes and triggers

Milk products contain lactose, which is also referred to as lactose. Lactose itself can not be absorbed by the intestinal mucosa, but only the individual sugars that make it up. This means that the milk sugar must first be broken down with the help of an enzyme so that it can enter the blood via the intestinal mucosa. The enzyme is called lactase. It is normally produced by the mucus cells in the small intestine - but not or not enough in people with lactose intolerance.

The result: the lactose continues to migrate from the small intestine into the large intestine. There he serves bacteria as food. This waste products remain, which then trigger the typical symptoms. These waste materials include lactic acids, short-chain fatty acids and gases such as hydrogen, carbon dioxide and methane.

Mechanism of lactose intoleranceIn lactose intolerant people, little or no lactase is produced. The consequence: The lactose can no longer be split and reaches the large intestine. There, certain bacteria ferment the lactose.

Although the cause of lactose intolerance is ultimately a deficiency of the enzyme lactase, this deficiency can come in several ways. Accordingly, the symptoms are different and can occur at different ages for the first time.

Primary lactose intolerance is very common

Actually, lactose intolerance is not a disease. Across the world, adults who can digest lactose are even the exception. It's different with babies. Newborns can normally metabolize lactose without any problems. Breast milk also contains lactose, even more than cow's milk. But already after the first months of life, the amount of the enzyme gradually decreases.

If it falls below a certain level, lactose intolerance symptoms appear. When this time is reached is different. Therefore, the age varies when so-called primary lactose intolerance begins. The victims are usually between five and twenty years old. In children under the age of five lactose intolerance rarely occurs. Most of the time, the first symptoms appear in adolescence. Primary lactose intolerance is by far the most common form of lactose intolerance.

Incidentally, the enzyme production does not completely set. Most sufferers still have a small amount of the enzyme. There are large individual fluctuations, which is why some people with lactose intolerance still tolerate a certain amount of lactose in the diet, others react to even the smallest amounts with complaints.

That about one third of humanity can digest lactose for life is due to a genetic mutation. Scientists assume that this change in DNA originated in Central Europe about 7500 years ago. Although the amount of lactase in these people also decreases, it remains large enough to continue to split lactose.

This condition could have been a survival advantage at that time. For with the beginning of livestock milk was present in large quantities and became an important source of food. Even today, every person who has no lactose intolerance is the carrier of this genetic change.

Acquired (secondary) lactose intolerance

Unlike primary lactose intolerance, secondary lactose intolerance is the result of another disease. The production of lactase is not natural, but throttled by damage to the intestinal mucosa. Triggers are sometimes major operations in the gastrointestinal tract, autoimmune diseases such as Crohn's disease or severe courses of gastrointestinal influenza. Also, gluten intolerance (celiac disease) is often the cause of secondary lactose intolerance, because the intestinal mucosa becomes inflamed in this disease and thereby the production of the enzyme lactase is impaired.

Usually secondary lactose intolerance returns as soon as the mucosal cells have recovered in the intestine. In rare cases, however, it can become chronic. It always depends on the severity of the causative disorder.

Calcium-Rich NutritionIf you do not use dairy products, you should eat other calcium-rich foods.

Congenital lactose intolerance in the baby

Innate lactose intolerance is a very rare form of the disease. In her case, the body can either produce no lactase at all, or only in tiny amounts due to a genetic defect from the beginning of life. One therefore speaks of an absolute lactose intolerance. The affected babies already get persistent diarrhea through the breast milk after a few days. Breastfeeding is not possible. Under certain circumstances, the uncleaved lactose can even get into the bloodstream via the gastric and intestinal mucosa and cause severe poisoning there. As a therapy is only a lifelong waiver of lactose in question.

However, if newborns have milk sugar problems, it is not necessarily a congenital lactose intolerance. The digestive tract can generally be very sensitive during the first weeks of life. Sometimes the lactase production is not working properly, but usually this problem will soon go away.

Lactose intolerance due to bacterial colonization of the small intestine

In some journals it is discussed whether possibly a deficient colonization of the small intestine with bacteria can lead to a lactose intolerance. Normally, bacteria and other microorganisms are found mainly in the colon. This is completely normal and even very important for digestion. Under certain circumstances, however, it may lead to an increased colonization of the small intestine, which is problematic.

On the one hand, the colonization of the small intestine mucosa - and thus the production of lactase - can be impaired. On the other hand, the bacteria in the small intestine begin to decompose the lactose before it can be split by the lactase. Still, there is no clear research that confirms this assumption. However, some studies show that in some cases lactose intolerance disappears as soon as the small bowel malady is treated with antibiotics.