Introduction
Diarrhoea after milk consumption describes the occurrence of thin stool with increased stool frequency, which is related to the time of previous milk consumption. Diarrhoea is medically defined as more than 3 bowel movements per day with high water content. However, the term diarrhoea is also often used to describe a single stool stoppage.
Causes of diarrhoea after milk consumption
If diarrhea symptoms occur repeatedly after the consumption of milk or milk products, this may be an indication of lactose intolerance. If the symptoms do not occur after each consumption of milk but only occasionally, lactose intolerance is rather unlikely. Other possible causes of diarrhoea, which is related to the time when milk is consumed, are the consumption of expired milk, gastrointestinal infections or other intolerances.
For more general information we recommend our page on: Causes of diarrhoeaThe classic leading symptom of lactose intolerance is diarrhoea, which occurs relatively shortly after the consumption of milk products. 15-20% of people in Germany are lactose intolerant. This is comparatively little compared to 70% of the world population.
Lactose intolerant means that there is an enzyme deficiency. Lactase is an enzyme that occurs in the small intestine and breaks down the lactose contained in dairy products and thus makes them digestible. If this does not happen, the lactose reaches the lower digestive tract undigested and is decomposed by bacteria.
This produces gases that lead to flatulence, diarrhoea and abdominal pain. A distinction is made between primary and secondary lactose intolerance. In the secondary form there is only a temporary reduction in lactase activity, for example in the context of gastrointestinal infections or in diseases such as celiac disease (gluten intolerance) and inflammatory gastrointestinal diseases such as Crohn’s disease or ulcerative colitis.
Accompanying symptoms of diarrhea after milk consumption
Typical accompanying symptoms of recurrent diarrhea after milk consumption are abdominal pain, abdominal cramps, nausea, flatulence and a feeling of fullness. The symptoms of lactose intolerance occur at the earliest about 30 minutes after milk consumption and can last for 6-9 hours. Often the affected persons can tolerate a certain amount of milk (products) because a certain enzyme activity is still present.
If this threshold is exceeded, i.e. if more milk product is consumed than can be broken down by the lactase still present, the symptoms mentioned above occur. The severity of the symptoms can vary depending on the amount of milk product ingested. It is quite possible that a small amount of milk in coffee does not cause any symptoms for some people with lactose intolerance, while for others this amount is sufficient to cause diarrhoea and abdominal pain.
Larger amounts of lactose, however, cause discomfort for everyone with lactose intolerance. Since diarrhoea after milk consumption is often caused by lactose intolerance, you should also read our page on: Symptoms of lactose intoleranceBlähungen are a typical accompanying symptom of diarrhoea after milk consumption. If lactose intolerance is present, flatulence is caused by the fact that lactose that is not sufficiently absorbed in the small intestine reaches the large intestine and is decomposed by the intestinal bacteria that have settled there. This produces gases which can cause abdominal pain, a feeling of fullness and flatulence.
