Essential for our well-being
The intestine is the largest organ in the human body. Measuring up to eight metres, it meanders through our middle and is divided into the large and small intestine. The individual sections of the significantly longer small intestine are known as the duodenum, jejunum and ileum.
Although the intestine is only a few centimetres in diameter, it unfolds to cover a surface area of 400 to 500 square metres – roughly the size of two tennis courts. So how does it fit into our body? The answer is as simple as it is astounding: The intestinal mucosa is highly folded and covered in villi which project into the intestinal cavity like millions of little fingers. This increases the surface of the intestine many times over.
It creates lots of space for our intestinal inhabitants: Around 100 billion bacteria live in our intestine, where they regulate digestion. They break up indigestible nutrients from our food and produce vital substances such as vitamins and butyric acid. As a whole, the micro-organisms located there are referred to as intestinal flora or microflora, and experts also use the terms microbiota or microbiome.
The intestinal flora acts as a natural barrier against pathogens and stimulates the intestinal mucosa to produce the body's own antibiotics against harmful bacteria. As a permanent training partner for the immune system, the intestinal flora control important processes for immune responses throughout the body. In total, around 80 per cent of all immune cells are located in the intestine.
Environmental influences, poor nutrition, medication and stress can change the composition of the intestinal flora and increase the permeability of the intestinal mucosa. A harmful bacterial colonisation can lead to a number of illnesses such as irritable bowel syndrome, recurrent infections of the upper airways and inflammatory bowel disease.
A healthy intestine is therefore vital for our health.