The Gut Barrier – The Key to Our Body’s Immune Protection


While the role of the digestive system in the body’s immunity and defence against diseases is increasingly being discussed and studied, a question often arises – what is the actual link between digestion and immunity? 

When microorganisms and various environmental toxins reach the digestive system, the intestinal epithelium acts as a barrier between the external environment and the body. Acting as a kind of immunological sensor, its function is to trigger a series of reactions when it comes into contact with antigens – substances that the body considers foreign or potentially dangerous. In order to protect us, the gut barrier must remain impermeable to potentially harmful substances from the environment, but also retain a degree of permeability to allow the transport of digested nutrients that the body needs to function. Thus, in addition to the microbiological barrier comprising the microbiota and intestinal mucosa, there is also the physical gut barrier, made up of the epithelial cells and connective tissue, and containing some 80% of our immune system cells – which sheds light on the link between digestion and the immune response. 

The microbiota is a living ecosystem that is influenced by a variety of factors. The most important ones are related to diet, taking medication, and exposure to stress and harmful substances. In fact, a poor diet (as a major factor) and chronic, day-to-day stress result in a change in the composition of the microbiota and compromise the integrity of the gut barrier, leading to leaky gut syndrome. This condition allows microorganisms, toxins and undigested food to cross into the bloodstream, leading to a vicious circle of infections and increasing both intestinal and systemic inflammation, ultimately resulting in an inadequate immune response. This is accompanied by a range of problems, including bloating, food sensitivities, fatigue, indigestion and skin problems. 

The globalisation of food has made fast food and low-quality food products very cheap and readily available, leading to a sharp increase in the consumption of foods that are poor in nutrients but very high in sugars, refined fats and various additives. This eating pattern is referred to as the Western diet and, together with a sedentary lifestyle, is what we call the Western lifestyle.  

There are now studies that show that such a diet and lifestyle have a direct impact on digestive health, in particular by compromising the balance of the gut microbiota, as well as the integrity of the intestinal mucosa, resulting in impaired digestion and reduced absorption of nutrients, which are already scarce in this diet. 

The only remedy is to make lifestyle changes to break the vicious cycle, and the first step is to change your diet. Foods rich in fibre, probiotics, phytonutrients, vitamins and minerals that have antioxidant and anti-inflammatory properties play an important role in supporting the gut barrier and ensuring a balanced microbiota. 

Fruit, vegetables, legumes, nuts and wholegrain cereals are food groups rich in complex carbohydrates and dietary fibre, which are essential for normal gut function. They also provide phytonutrients that reduce the risk of several diseases and directly contribute to improved digestion and absorption of nutrients due to their synergistic effects with vitamins and minerals from food. 

An adequate intake of healthy fats is also important, with an emphasis on unsaturated fatty acids found in fish, avocado, nuts and olive oil. Oily fish contain omega-3 fatty acids, which have an anti-inflammatory effect and promote microbiota diversity, maintaining the gut barrier and benefiting the immune system. Fermented foods such as yoghurt, soft cheeses, kefir, acidophilus milk, sourdough bread, tempeh, and so on contain probiotics, which have a positive effect on digestive health, promote microbiota diversity, directly benefit brain health through the gut-brain axis, contribute to the immune response and play a vital role in maintaining the gut barrier. 

Furthermore, fish and dairy products are an important source of vitamin D, which is necessary for normal cell growth, nerve and muscle function, and a healthy immune system. Recent evidence suggests that vitamin D contributes to maintaining the integrity of the intestinal mucosal barrier by strengthening the intercellular junctions that control mucosal permeability, while also reducing the levels of inflammatory molecules. Because of the effects it has on the intestinal mucosa, maintaining sufficient vitamin D levels may be vital for the health of the gut microbiota and immunity. 

Selenium and zinc, minerals found in red meat, fish and seafood, also have beneficial effects on gut health and the health of the gut barrier. As one of the most powerful antioxidants, selenium benefits the gut flora and helps to control the inflammatory response. A lack of selenium and zinc increase inflammation and oxidative stress, resulting in damage to the intestinal mucosa, which can result in intestinal permeability. 

Therefore, the food we eat every day should contain as many substances that protect gut barrier integrity as possible.  In short, variety, moderation, and combining whole foods are the cornerstones of a healthy diet that supports normal digestive function and immunity.   

How can Donat help with disease prevention and adopting healthy habits?

Thanks to its unique mineral composition, Donat is a 100% natural mineral water that has beneficial effects on digestion and is clinically proven to be effective. Taking care of your digestion is taking care of your overall health. After eating, food takes about six to eight hours to pass through the stomach and small intestine. Next, it enters the large intestine, where the final phase of digestion takes place. The large intestine is where the body gets rid of waste matter and undigested food remains, so it’s very important to maintain regular digestion. This final stage of digestion is essential because if harmful substances and metabolic waste products build up in the body, the whole digestive process slows down and the absorption of nutrients is reduced. Digestion provides the body with water, mineralsvitamins and energy, so it’s clear that improving your digestive function is one of the key steps to improving your health. And let’s not forget that a large part of the immune system is located in the gut. Roughly 80% of the immune system’s cells are found in the intestines, making them our largest immune organ. Through the digestive system the body absorbs nutrients that are then used to boost the immune system and fight disease. This is why it’s so important to maintain the health of the digestive system and thus overall health. 

Taking care of your health is more important than ever, and we all know that a healthy lifestyle plays a vital role in preventing many of the ailments and diseases of contemporary life. Along with a healthy diet and lifestyle, it’s highly recommended to drink Donat natural mineral water on a daily basis. Apart from stimulating the digestive system and supporting its function in its final stage, Donat has beneficial effects on other parts of the digestive system, promoting their healthy functioning. Magnesium plays an important role in digestive processes. High levels of magnesium stimulate the release of bile and pancreatic enzymes into the small intestine, which is vital for digestive processes and nutrient absorption. In addition, sulphate ions enable bile flow from the liver, stimulate gallbladder contractions and thus reduce the probability of gallstone formation. We should also keep in mind that bile plays a major role in the digestion of fats. Bile salts split fats from food into smaller particles, which are then available for enzymes to break down.

By drinking half a litre of Donat a day you’ll improve your digestion in a natural way, thus allowing your body to absorb the necessary nutrients that are consumed as part of a healthy diet and are important for strengthening the immune system. With the Donat digestive system support programme, you can drink Donat daily and on a long-term basis: 

Optimal way of drinking Donat as a preventive

Method of drinking
In the morning on an empty stomach
0.2 – 0.3 litres
Before lunch
0.1 litres
Before supper
0.1 – 0.2 litres

Have you decided to try
this drinking program?

Download the application which will make sure that you never forget to drink Donat in your chosen drinking program.


Have you decided to try
this drinking program?

Download the application which will make sure that you never forget to drink Donat in your chosen drinking program.



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Nutrition Under Stress And Emotional Eating