Gastrointestinal tract - Function & Keeping it healthy

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Intestinal function - This is how important the intestine is for humans2

If the term "bowel" is dropped in a conversation most of the participants probably scrunch up their noses. We do not like dealing with a topic like digestion - and certainly not with its tasks. Or even the results. Too unpleasant, almost unspeakable. We should quickly reconsider this attitude. Because the intestine is an incredibly fascinating, complex organ - with far-reaching effects on health and general well-being. 

It's good seven metres long: the human intestine. Only about one metre of this impressive total length is attributable to the colon, as the rest is made up of the preceding, serpentine-like small intestine. The tasks of the two intestinal sections are varied - and perfectly matched.

The small intestine: a giant in a small space

The main part of the actual digestive work is done by the small intestine. It receives the well-minced chyme, mixed with gastric juice from the stomach and directly begins with the further processing. At this point the chyme is still too “chunky” to be actually absorbed and used by the body. The release of main part of the digestive enzymes (for example by the pancreas) should change that: they crush the ingredients of the food down to their smallest possible building blocks. 

Once the enzymes have done their work, the small intestine absorbs the nutritional elements and transfers them to the blood and lymph. From there they reach everywhere in the whole body. In order to work as effectively as possible and to fully exploit the food the intestine is not only labyrinthine: its surface is also heavily folded - and on these protuberances sit further folds, the so-called intestinal villi.

Thus, the small intestine reaches an incredible surface of up to 500 square meters - which is about the size of a basketball court! Thus, a very big surface is able to absorb nutritional components.

In addition to the digestion and absorption of nutrients the small intestine has other important tasks. These include: 

  • The formation of hormones that coordinate the digestive process 
  • The intake of water from chyme 
  • The mincing of the intestinal contents 

Exactly matched intestinal movements ensure that the chyme is sufficiently in contact with hormones, enzymes and the intestinal surface to absorb the important nutrients.

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The colon: a leftover-utilizer

The small intestine already filters what the body can use from the food. But this does in no way mean that the colon is idle: It continues to extract water and salt from the chyme and finally prepare the stool.  

Whatever reaches the large intestine undigested, is metabolised by the intestinal bacteria: countless different species process the indigestible components of our food. The leftovers, along with the waste substances are pushed by the colonic musculature towards the rectum, up to the descending part of the colon. There the stool is stored until it can be excreted through the anus. 

Due to its physiological tasks, the colon visually differs from the preceding small intestine: instead of numerous turns and folds the colon wall has reinforcements and a larger circumference.

The intestinal flora: important protective shield of humans

All microorganisms that are native to the intestine belong to the so-called intestinal flora. It includes not only the intestinal bacteria - which account for the largest cohort - but also other protozoa and fungi. 

Interesting: In an adult human alone intestinal bacteria account for about 1.5 kilograms of body weight. 

Their job is by no means only digestive. They are discussed to contribute also to the general health status and the immune status.  

The intestinal flora is undoubtedly an essential part of our digestive system. We often become aware of its importance, only when it gets out of balance. This can happen for example as a result of antibiotic treatment: antibiotics are said to kill harmful bacteria in the body but in many cases they also get the "good" gut bacteria. If the microbiome does not recover properly from antibiotics therapy, this may result in diarrhea.  

Additionally, an imbalance of the intestinal flora is discussed to be involved in the development of a number of diseases including depression.

How can intestinal function be stimulated and is it important?

If the intestine does not work properly, this may burden you. Therefore, a balanced intestinal function is the basis for our overall well-being. An unhealthy lifestyle may promote such intestinal symptoms.

Nowadays nutrition contains too little fibre. According to German data from the National Consumption Study II, 75% of women and 68% of men have a fibre intake below the guideline of at least 30 g per day. Too little fibre makes the intestine lazy, since the fibre’s job is to promote intestinal function by binding water. This ensures physiologically normal intestinal transit and prevents the stool from becoming too hard. Fibres need liquid to swell. The recommended intake of liquid per day per human is 2,5 litres. Sadly, this does not include the daily beer or the occasional glass of wine, but you can enjoy these on top. 

To a certain extent, you can positively influence intestinal symptoms yourself. For example, through more relaxation in everyday life or an individual diet that is good for you. In general, just listen to your body and learn to recognize factors, which might trigger your symptoms. You may choose one of the following changes for you. What works in the end varies from person to person:


Avoid too much stress and find a balance to your professional life. Try some suitable “soft” sports such as yoga or walking.  

Keep moving: 

It doesn't always have to be the gym. Often it’s sufficient to integrate more exercise into your everyday life, such as taking the stairs, going for a walk during lunch break or cycling for short distances. 

Eat regularly: 

Regular mealtimes also lead to regular digestion in many people. Try not to miss a meal. Some people can better tolerate five smaller dishes over the course of the day than, for example, two very large ones - try what suits you and stick with it. 

Eat slowly: 

Take your time for each and every meal and do not gobble up, but chew thoroughly and enjoy it  

Eat fresh: 

Avoid processed foods, which are high in additives, trans fats and artificial sweeteners. Instead eat more whole foods with essential nutrients and vitamins  

Eat healthy: 

It is not a question of going without chips and pizza for ever and ever, but of having a healthy focus. In a nutshell: Try eating lots of vegetables, replace white flour products with wholemeal products, a little healthy vegetable oil and a handful of fruit each day- that's all you need for a start. A few food components, by the way, are considered to be particularly gut-friendly – dietary fibre, prebiotics and probiotics. You can read more about them here:

Learn more

Intestinal complaints - what problems can arise?

Despite the unpleasantness of the topic, the bowel is one of the most important organs in the body. If the digestive system is out of balance and not performing well, it can have a serious impact on health and general well-being. Affected persons might experience intestinal complaints, which can be distinguished in two categories – specific and unspecific.  

Specific intestinal complaints are symptoms directly related to the GI tract: 

  • Bloating 
  • Diarrhoea 
  • Constipation  
  • Feeling of abdominal fullness  

Unspecific complaints, which may be related to imbalances in the GI tract may occur additionally / concurrently: 

  • Headaches 
  • Increased susceptibility to infections  
  • Fatigue 
  • Depressed mood 
  • Skin problems
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What causes intestinal problems?

Causes of intestinal problems may be of various kinds but the commonly known ones can be traced back to diseases like: 

  • Irritable bowel syndrome 
  • Irritable stomach 
  • Infections of the gastrointestinal tract with viruses, bacteria, fungi and other parasites  
  • Intolerances or allergies towards certain foods 
  • Irritation or inflammation of the appendix 
  • Inflammation of pouches in the wall of the colon (Diverticulitis)  
  • Haemorrhoids 
  • Intestinal cancer or intestinal polyps, representing a preliminary stage for the cancer 

Beside of a potential disease, intestinal problems can also be caused by a wrong or poor diet, the lack of exercise, stress or the use of certain medication like antibiotics. Another possible cause are functional gastrointestinal disorders such as irritable bowel syndrome or irritable stomach. These are disorders that don’t have their origin in an organic cause, but which can nevertheless trigger very stressful symptoms. If you are unsure where your symptoms are coming from or if you suspect that you have a medical condition, do not be afraid to seek out a physician.  

It is not always easy to identify gastrointestinal issues, as many factors play a role. So your doctor will try to get the best possible picture of your situation: they may ask you about your complaints and any already diagnosed illnesses. Also they will discuss your known triggers, the duration, location and the type of pain you might have experienced, as well as any accompanying symptoms, since all these factors play an important role in isolating the problem. Your physician may further ask you about your general eating habits, any changes in stool or urine composition as well as about any changes in your weight. They might also monitor your gastric sounds or perform an ultrasound exam of the stomach to reach a diagnosis. Sometimes a blood test or a gastroscopy or colonoscopy is necessary.

How can these problems be treated effectively?

Depending on the diagnosis, your doctor will suggest the most suitable therapy for you. If the gastrointestinal problems are related to a functional GI disorders like irritable stomach or irritable bowel syndrome, which have no organic cause, the main purpose of the therapy is to alleviate the symptoms.

Additionally, you can think about what triggers your symptoms and change your living and eating habits if necessary. A healthy lifestyle and avoiding food that may cause individual problems can lead to better digestion. Some good approaches to more relaxation in everyday life and how a high-fibre diet may help can be found in the chapter "How can intestinal function be stimulated and is it important? Nevertheless, if all this does not help, you can also use the healing power of herbs. Thanks to the unique combination of nine medicinal plants, Iberogast®, for example, can act on multiple digestive symptoms of functional gastrointestinal disorders and their underlying causes - simultaneously (multi-target principle), thus alleviating various complaints in the gastrointestinal tract.

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The stomach

The human stomach: a sophisticated system that works flawlessly and fits together perfectly. Learn more about the function and structure of the stomach here.

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Disturbances in the gastrointestinal tract are usually not only extremely unpleasant and associated with numerous complaints, they often make a normal everyday life even harder. It’s good that there is Iberogast®: The combination of nine medicinal plants targets both the underlying causes and the annoying symptoms.

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