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Crohn’s disease: possible causes of chronic illness

Scientists have been intensively researching Crohn’s disease and its causes for years. Nevertheless, the disease still poses a number of mysteries. It seems that several factors play a role in its onset.

Basically, the barrier function of the intestinal mucosa is disturbed in Crohn’s disease patients. This allows bacteria to penetrate the intestinal mucosa that have no business being there. As a result, the immune system jumps into action and activates inflammatory cells. This reaction is very strong in Crohn’s disease patients and leads to chronic inflammation, which in severe cases can extend to the entire digestive system. The symptoms range from painful diarrhoea to inflammation of the oral mucosa.

What factors can increase the risk of developing Crohn’s disease? And can an outbreak of the disease be prevented?

Is Crohn’s disease hereditary?

Scientists have already identified over 70 genes that may play a role in the development of Crohn’s disease. Changes in certain genes can increase the risk of Crohn’s disease. However, gene mutations are usually not solely responsible for the onset of the disease. Even those who have a genetically increased probability of developing Crohn’s disease often remain healthy. The connections that lead to the outbreak of the intestinal disease seem to be extremely complex and are influenced by external influences as well as the microbial conditions in the intestine, among other things.

Environmental factors increase the risk of disease

Numerous studies have already tried to find out the connection between various environmental factors and Crohn’s disease. Some conditions seem to influence the risk of developing the disease:


the country you live in


whether you live in a rural region or in a city

Environmental conditions

the hygienic conditions prevailing there

Lifestyle influences the course of the disease

However, not only the place where one lives has an influence on the disease, but also the basic way of life. The following factors have a negative effect on the course of the disease:

  • lack of exercise
  • unbalanced diet
  • absorption of few dietary fibres and many carbohydrates at the same time
  • sleep disorders
  • physical and psychological stress
  • psychiatric diseases such as depression
  • smoking

For successful treatment of Crohn’s disease, patients should try to avoid these negative influences if possible. These factors are not the cause of Crohn’s disease, but some influence on the course of the disease is considered certain. The negative effects of smoking have already been proven in many studies. For smokers the risk to develop Crohn’s disease is twice as high as for non-smokers. In addition, the relapse rate after bowel surgery is significantly higher in smokers.

The role of intestinal flora in Crohn’s disease

A strong and permanent inflammation in the intestine also has effects on the intestinal flora. The extent to which an imbalance in the intestinal bacteria can trigger Crohn’s disease is still being investigated. However, studies have already shown that a link is probable. Because in chronic inflammatory intestinal diseases – which include Crohn’s disease as well as ulcerative colitis – the balance in the intestine is often disturbed. This dysbiosis (imbalance of the intestinal flora) already exists in many patients at the beginning of the disease. It could therefore be that the disturbed intestinal flora favours the outbreak of inflammation.

The microbes in the intestine play an important role in regulating the immune system – and thus also in promoting or preventing inflammation. If the balance between the bacteria is disturbed, it is possible that the majority of them are the ones that cause inflammation.

Other possible causes of Crohn’s disease

According to current knowledge, genetic changes are the cause of Crohn’s disease – but not alone. Other factors such as lifestyle, nutrition and the condition of the intestinal flora are also of great importance. In addition to the above-mentioned factors, other causes of Crohn’s disease can also be considered:

antibiotic therapies
Infections (sometimes also infections that occurred during childhood)
certain fungi in the intestine

You cannot influence many of these possible triggers yourself – be it your genes or infections you had in childhood. But your bowel, for example, will always thank you if you take care of your diet.

You can do that for your bowel health

If you want to actively do something for your intestinal health, you must of course first know how your intestines are doing. After all, not every diarrhoea is caused by a serious or even chronic illness. Regardless of this, a balanced intestinal flora can generally improve your well-being. In the case of severe symptoms, however, a visit to the doctor and detailed examinations are always recommended.

With an intestinal flora test like INTEST.pro you can find out the composition of your intestinal flora and whether it lacks certain bacteria – or whether others are present in excessive numbers. For example, you can find out whether you have a lot of bacteria that cause inflammation or the bacteria that protect your intestinal mucus wall. The understanding of one’s own microbiota and the knowledge of a possible imbalance can help to get to the bottom of complaints. A connection between the condition of the intestinal flora and chronic inflammatory intestinal diseases is very likely, even if it is not yet clear what the cause is and what the consequences are.

Dr. Paul Hammer
CEO & Founder
Dr Paul Hammer is the founder and CEO of BIOMES NGS GmbH. Paul received his PhD in systems biology and bioinformatics in 2012.
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