If you suffer from lactose intolerance, the consumption of milk and dairy products triggers symptoms. This is caused by the absence or insufficient production of the digestive enzyme lactase. Lactase is produced in the small intestine and breaks down lactose into glucose and galactose.

If the small intestine produces too little or no lactase, lactose enters the colon where it is broken down by intestinal bacteria into hydrogen, carbon dioxide, lactic acid, and acetic acid. This causes diarrhea, nausea, bloating and cramping abdominal pain.
Lactose intolerance should not be confused with milk protein allergy. It is an allergic reaction with a corresponding production of antibodies to the milk protein.

For diagnosis of lactose intolerance, a special test is used. After taking 50 grams of lactose, the hydrogen content in the breath or the blood glucose is measured.

The basic principle of therapy is the avoidance or restricted consumption of milk and dairy products, depending on the severity of the disease.

The severity ranges from a complete intolerance to a slight intolerance. Ultimately, for each person affected, it is important to know what amount of lactose he/she tolerates without symptoms. Very rarely, there is a gluten intolerance even in very small amounts of lactose (less than 3 grams). Usually food with small amounts of lactose (and eaten in small quantities) is tolerated without problems.
Sour milk products such as yogurt and many cheeses are well-tolerated in spite of high milk sugar content, because the contained lactic acid bacteria in yogurt already breaks down most of the lactose.
In severe cases of lactose intolerance you can also take the digestive enzyme lactase. The simultaneous intake of dairy products and lactase prevents the familiar symptoms.